Download Glossary of Histology - Name - Дніпропетровська медична академія

ДНІПРОПЕТРОВСЬКА МЕДИЧНА АКАДЕМІЯ
DNIPROPETROVSK MEDICAL ACADEMY
КАФЕДРА ГІСТОЛОГІЇ
DEPARTMENT OF HISTOLOGY
Glossary of Histology
(with microphotograph index)
Igor V. Tverdokhleb, Ph.D.
(Department of Histology, Dnipropetrovsk Medical Academy)
Дніпропетровськ - 2013
Dnipropetrovsk - 2013
2
A
•
Photomicrograph of breast adenocarcinoma
adenohypophysis
anterior lobe of the pituitary; composed of
glandular secretory tissue
adipocyte
large cell (up to 200 um in diameter) with
only a thin rim of cytoplasm due to the
presence of a large flat droplet; TEM
shows an external lamina; stores large lipid vacuoles
•
Photomicrograph of adipocyte
•
Photomicrograph of adipocyte
A band
a region containing the full length of the
myosin filaments and also parts of actin
filaments; located in the sarcomere of skeletal muscle; see also H band
•
Photomicrograph of A band
absorptive cell
Cell that is efficient in absorbing substances from the lumen via apical cytoplasmic processes (microvilli or stereocilia)
•
Photomicrograph of absorptive cell
adipose tissue
a grouping of adipocytes
•
Photomicrograph of adipose
•
Photomicrograph of adipose
acidophil
cell of the adenohypophysis which stains
pink red; i.e. somatotropes and mammatropes
•
Photomicrograph of acidophil
adrenocorticolipotrope
cell of the adenohypophysis which produces ACTH and LPH
adventitia
connective tissue with high content of adipose, nerves, and blood vessels
acinar cell
a cell of an acinus unit
•
Photomicrograph of breast adenocarcinoma
afferent arteriole
vessel that branches from an interlobular
artery and supplies the glomerulus
acinus
cells arranged into a circular secretory unit
(i.e. pancreatic acinus and mucous acinus)
afferent lymphatic vessel
a vessel involved in bringing lymph to the
lymph node
•
Photomicrograph of afferent lymph
vessel
acrosome
dense structure of the anterior portion of a
sperm cell; contains enzymes that allow it
to penetrate the egg during fertilization
alpha-actinin
protein that anchors actin to the Z-disk
actin
thin filament protein which allows contractility and confers support in cells
alveolar duct
long airway lined only with alveolar cells
and some smooth muscle
adenocarcinoma
malignant cancer with cells arranged in a
gland-like pattern; i.e. prostate and breast
adenocarcinoma
alveolar macrophage
macrophage located in the alveolar space
3
and its surrounding connective tissue;
serves to remove inhaled particles; also
referred to as "dust cell"
anterior chamber of eye
space between the cornea and the iris;
filled with aqueous humor
alveolar sac
alveoli cluster surrounding an air space;
found at the end of alveolar ducts
anterior lobe
see adenohypophysis
anthracoid pigment
black debris found in the alveolar macrophages of those individuals chronically
exposed to smoke
•
Photomicrograph of anthracoid in
dust cell
alveolar wall
the site where alveoli exchange gas with
the blood; composed of:
•
alveolar epithelium
•
alveolar basal lamina
•
endothelial basal lamina
•
endothelium
antigen-presenting cell
a cell that processes and presents antigens
to lymphocytes; this category includes:
•
macrophages
•
Kupffer cells
•
reticular cells
•
Langerhans cell
alveolus
1) the basic unit of gas exchange; small
air-filled chamber lined by squamous cells
2) mammary gland secretory structure;
lined by cuboidal cells and myoepithelial
cells
•
Photomicrograph of alveolus
antrum
cavity inside the secondary and Graafian
follicles
amnion
innermost membrane surrounding the
embryo
•
Photomicrograph of amnion
apical surface
that side of the cell facing the lumen; typically the site of secretion and reception of
substances (i.e. hormones, antibodies, and
nutrients)
ampulla of uterine tube
see oviduct
anal apocrine gland
gland of the anus associated with hair follicles
apocrine sweat gland
large sweat gland associated with hair follicles in the eyelid, axilla, areola, anal region, and genitalia
anal gland
branched, straight tubular mucus gland
extending into the submucosa
apoptosis
controlled cellular death in which the organelles are packaged in membranes for
eventual phagocytosis; apparent as a
shrinkage in cell size and a pyknotic nucleus
anal transitional zone (ATZ)
area where the simple columnar epithelium of the rectal mucosa meets an area of
stratified squamous epithelium
appositional growth
bone growth due to addition of new matrix
by osteoblasts in bone or chondroblasts in
cartilage
anchoring villi
see basal plate
4
atrophy
a wasting away of muscle due to denervation or disuse
APUD cell
endocrine cell of the digestive tract; activated by nervous stimulation
•
Photomicrograph of APUD cell
Auerbach's plexus
ganglion cell group between the two muscle layers of the muscularis externa in the
digestive tract; controls motility of the digestive tract
aqueous humor
watery fluid of the anterior chamber and
posterior chamber of eye
arcuate artery
branch of the interlobar artery; traces a
course along the base of the renal pyramid
axon
extension of neurons which transmits signals to other neurons or effector cells
•
Photomicrograph of axon
arcuate vein
vessel carrying blood away from the kidney medulla; traces a course along the pyramid base
axon hillock
the point from which the axon emerges
from the neuron body
arrector pili muscle
small muscle attached to the base of a hair
follicle
azurophilic granule
the lysosome of leukocytes
arteriole
vessel with 1-2 layers of smooth muscle;
leads to a capillary
•
Photomicrograph of arteriole
B
artery
vessel which takes oxygen-rich blood
from the heart to tissues
ascites
fluid found in the peritoneal cavity; consists of mesothelial cells, red blood cells,
leukocytes and may contain cancer cells
•
Photomicrograph of ascitic fluid
BALT
Bronchus Associated Lymphatic Tissue;
lymphatic aggregations of the respiratory
system
atherosclerotic plaque
necrotic mass of lipid and cells
(macrophages, smooth muscle cells, and
fibroblasts) resulting from endothelial
damage
band cell (neutrophilic)
precursor to the neutrophil with an "S"
shaped nucleus
•
Photomicrograph of neutrophilic
band cell
atretic follicle
disintegrating follicle within the ovary;
has not undergone ovulation
band form
juvenile/immature forms of granulocytes
with "U" or "S" shaped nuclei; immediate
precursors to the mature forms
5
•
Photomicrograph of neutrophilic
band cell
sesses vasoactive and immunoreactive
substances similar to those of mast cells
which are released after IgE binding; nucleus often obscured by coarse cytoplasmic
blue (H&E) granules in cytoplasm.
•
Photomicrograph of basophil
2) cell of the adenohypophysis which
stains blue-purple; includes: adrenocorticolipotropes, gonadotropes, and thyrotropes
•
Photomicrograph of pituitary basophil
basal body
structure derived from the centriole which
organizes the microtubules of cilia
•
Photomicrograph of basal body
basal cell
a cell type that comprises the bottom layer
of
epithelia;
serves
as
precursor/replacement for the cells above it
•
Photomicrograph of basal cell
basophilic erythroblast
erythrocyte precursor slightly smaller than
the proerythroblast; has deeply basophilic
cytoplasm; EM reveals considerable numbers of polyribosomes present (beginning
of hemoglobin synthesis at this stage); division of basophilic erythroblast gives rise
to polychromatophilic erythroblast
•
Photomicrograph of basophilic
erythroblast
basal lamina
noncellular, protein-polysaccharide layer
which anchors an epithelium to the connective tissue beneath; also known as
'lamina densa' known in light microscopy
as basement membrane
basal plate
maternal side of the placenta; many blood
vessels traverse here to supply the intervillous space; contains numerous anchoring villi which attach it to the chorionic
plate
•
Photomicrograph of basal plate
bile
product of the liver stored in the
gallbladder and released into the duodenum; allows for solubilization and uptake
of lipids
basal surface
that side of the cell that is anchored to the
basal lamina or to other cells; faces away
from the lumen
bile canaliculus
"canal" between two adjacent hepatocytes;
site of bile release from the hepatocyte
•
Photomicrograph of bile canliculus
basement membrane
Light microscopic term for basal lamina
bile duct
ducts which carry bile from the liver parenchyma; bile ducts fuse to form the hepatic duct
•
Photomicrograph of bile duct
•
Photomicrograph of bile duct
basilar membrane
membrane within the cochlea; its vibrations allow for frequency determination,
with high frequency sounds discriminated
at the base, and low frequency sounds at
the apex
•
Photomicrograph of basilar membrane
blast cell
the earlier precursor of blood cells
blood vessel
structure that carries blood and bloodborne substances; lined by smooth muscle;
basophil
1) least in number of all leukocytes; pos6
types include:
•
artery
•
arteriole
•
venule
•
vein
•
capillary
site of plasma filtration; a double-layered
cup-shaped structure that surrounds the
glomerulus
Bowman's gland
"olfactory gland"; the secretion of this
serous glands traps and dissolves odorproducing particles in the nasal cavity to
allow for new smells to be detected
blood-testis barrier
the junctional complex between adjacent
Sertoli cells; keeps developing germ cells
isolated from potentially harmful antibodies of the circulation
Bowman's membrane
basal lamina of the corneal epithelium
•
Photomicrograph of Bowman's
membrane
•
Photomicrograph of corneal epithelium
blood-thymus barrier
a barrier between lymphocytes and the
lumen of vessels in the thymus; consists
of:
•
capillary endothelium
•
basal lamina
•
connective tissue containing macrophages
•
basal lamina of epithelioreticular
cells
•
epithelioreticular cell layer
bronchial artery
branches of this vessel supply all lung tissue except for the alveoli
•
Photomicrograph of bronchial artery
•
Photomicrograph of bronchial artery
B-lymphocyte
see lymphocyte
bronchial vein
this vessel drains the connective tissue of
the lung hilus
bone
specialized connective tissue with a mineralized (hydroxyapatite) matrix
bronchiolar cell
also known as "Clara cell"; nonciliated
cell lining bronchioles that secretes a lipoprotein to prevent adhesion of the airway
walls
•
Photomicrograph of Clara cell
bone marrow
blood-rich material in the center of bone;
involved in hemopoiesis
•
Photomicrograph of bone marrow
bronchiole
structure extending from the bronchi to the
alveoli
•
terminal bronchiole- lined with ciliated cuboidal cells and bronchiolar cells;
scattered brush cells and a circumferential
smooth muscle layer are also notable features
•
respiratory bronchiole- continues
after the terminal bronchiole; bronchiolar
cells are abundant; some gas exchange can
occur here; alveoli extend from the ter-
bone-lining cell
flat cell that aligns bone surfaces; is an inactive osteoprogenitor cell
•
Photomicrograph of bone-lining
cell
bony callus
stage in bone repair; replaces the fibrocartilaginous callus after mineralization
Bowman's capsule
7
•
minal ends of this structure
•
Photomicrograph of bronchiole
Photomicrograph of canaliculus
cancer cell
cell that exhibits uncontrolled growth;
may spread throughout the organism affected
bronchus
see trachea
Brunner's gland
submucosal mucous glands of the duodenum
•
Photomicrograph of duodenal
gland
capillary
a small blood vessel which receives from
arteries and delivers to veins; thin endothelium is ideal for exchange of substances
•
Photomicrograph of capillary
brush border
the appearance of the numerous microvilli
of an absorptive epithelium
•
Photomicrograph of brush border
capillary space
the side opposite the urinary pole in the
glomerulus; contains blood
brush cell
a columnar epithelial cell of the respiratory system with numerous microvilli;
serves as a sensory receptor; basal surface
is in contact with a nerve ending
capsular matrix
material of the capsule consisting of sulfated proteoglycans
capsule
1)a covering layer of connective tissue of
the lymph node, spleen, testis, prostate
and other organs
•
Photomicrograph of lymph node
capsule
2)secreted matrix surrounding the lacunae
of chondrocytes
•
Photomicrograph of cartilage capsule
C
calcified cartilage
a stage of endochondral bone formation in
which cartilage previously laid down is
mineralized
carcinoma in situ (CIS)
a condition in which cancer cells are limited (at least temporarily) by the basement membrane from spreading to other
areas
canal of Schlemm
opening at the corneal-scleral junction
which drains the aqueous humor
•
Photomicrograph of canal of
Schlemm
cardiac gland
gland located within the stomach at its
junction with the esophagus; similar in
property to the esophageal cardiac gland
canaliculus
"tunnel" which allows osteocytes housed
in separate lacunae to communicate via
cytoplasmic processes
cardiac muscle
involuntary, striated muscle that makes up
the mass of the heart and lines some large
vessels (i.e. large branches of the pulmo8
central artery
name for the splenic artery within the
white pulp
•
Photomicrograph of central artery
nary vein)
•
Photomicrograph of cardiac muscle
cardiac myocyte
the elongate cell whose contractile and
electric communication properties allow
the heart to beat
•
Photomicrograph of cardiac myocyte
central vein
large vessel which drains the hepatic sinusoids
•
Photomicrograph of central vein
cartilage
tissue consisting of chondrocytes and a
surrounding matrix; types include:
•
elastic cartilage- cartilage with high
content of elastic fibers; found in external
ear, epiglottis, and larynx
•
Photomicrograph of elastic cartilage
•
fibrocartilage- cartilage with high
content of dense regular connective tissue;
found in intervertebral discs, menisci, and
the articular discs
•
Photomicrograph of fibrocartilage
•
hyaline cartilage- cartilage with an
amorphous matrix; found in articular
joints, tracheal rings, and knee cartilage
•
Photomicrograph of hyaline cartilage
centriole
cellular stucture involved in organizing
the microtubular apparatus and also the
mitotic spindle which is needed for faithful division of genetic material in cellular
division
centroacinar cell
a cell of the proximal intercalated duct
within the pancreatic acinus
•
Photomicrograph of centroacinar
cell
cervical gland
mucous gland of the cervical mucosa; secretes less viscous mucous during midmenstrual cycle
cervical mucosa
lining of the head of the uterus (cervix);
contains large branched glands; does not
undergo sloughing
cartilage plate
supporting structure found in good number in the bronchi; becomes smaller and
less numerous in smaller bronchial
branches
cervical myometrium
see myometrium
cartilage ring
C-shaped hyaline cartilage which maintains the tubular shape of the trachea and
the main bronchi
cervical stroma
see stroma
cell body
the main mass of the cell, from which various processes may extend
Chief cell
basophilic cell of the stomach fundic
gland that secretes pepsinogen and a weak
lipase
•
Photomicrograph of Chief cell
cell lineage
the full developmental stages of a given
cell
chondroblast
a cell that secretes cartilage matrix; referred to as chondrocyte when surrounded
9
by matrix
•
Photomicrograph of chondroblast
cell of the adenohypophysis which does
not stain
•
Photomicrograph of chromophobe
chondrocyte
see chondroblast
•
Photomicrograph of chondrocyte
chromosome
paired chromatids joined by a centromere;
the chromatids consist of chromatin; humans possess 23 paired chromosomes
chondrogenic layer
a region of cartilage formation
ciliary body
tissue located between iris and choroid;
produces the aqueous humor and houses
muscles which control lens shape
•
Photomicrograph of ciliary body
chorionic plate
fetal part of the placenta from which chorionic villi project
•
Photomicrograph of chorionic plate
•
Photomicrograph of chorionic plate
ciliary muscle
smooth muscle of the ciliary body that
controls the shape of the lens
chorionic villus
finger-like extension of the chorionic plate
which allows for maternal-fetal blood exchange; lined on the outer surface by the
syncytiotrophoblast and cytotrophoblast
and contains a core of fetal blood vessels;
the intervillous spaces contain maternal
blood; this arrangment allows for maternal-fetal exchange
•
Photomicrograph of intervillous
space
•
Photomicrograph of chorionic villus
•
Photomicrograph of chorionic villus
ciliated columnar epithelium
the typical epithelium of the respiratory
system; the cilia serve to move mucus and
inhaled particles
•
ciliated epithelium
ciliated epithelial cell
cell equipped with cilia; primarily in the
respiratory system and the oviduct
cilium
projection of certain cells containing microtubules which allows for cellular
movement or the propulsion of other particles (i.e. mucus, an oocyte, etc.)
•
Photomicrograph of cilium
choroid
vascular layer which provides nutrition to
the retina
•
Photomicrograph of choroid
circular fiber of ciliary muscle
allows lens to become more spherical
chromaffin cell
cell of the adrenal medulla which secretes
epinephrine and norepinephrine
•
Photomicrograph of chromaffin
cell
circumvallate papillae
large, dome-shaped structures anterior to
the sulcus terminalis of the tongue which
contain taste buds
chromatin
a tightly packed complex of DNA and histones (proteins) located in the nucleus
Clara cell
see bronchiolar cell
chromophobe
classical lobule
10
•
Type I: located in skin, bone, tendon, and ligaments; allow for resistance to
force, tension, and stretch
•
Type II: found in hyaline and elastic cartilage; provide resistance to pressure
•
Type III: connective tissue of organs and blood vessels; provide structural
support
•
Type IV: basal laminae of epithelia
and endothelium
•
Type VII: present in anchoring fibrils that secure the basal lamina to connective tissue
hexagonal model of liver organization
with six portal triads surrounding a central
vein
cleft of Schmidt-Lantermann
spaces within the myelin sheath containing Schwann cell cytoplasm
closed circulation theory
a model for splenic circulation in which
blood empties from splenic arterioles into
the sinuses of the red pulp
cochlea
the coiled structure located in the inner ear
that houses the auditory apparatus
•
Photomicrograph of cochlea (spiral
ganglion)
collecting duct
duct of the kidney cortex and medulla that
drains the tubule network into the larger
ducts of Bellini; lined by squamous cells,
cuboidal cells, and columnar epithelial
cells, in that order as the duct increases in
size
cochlear canal
space divided into the scala vestibuli superiorly and scala tympani inferiorly and the
scala media in the center
collecting tubule
tubule that emerges in the cortical labyrinth; a number of these merge to form a
collecting duct within a medullary ray
cochlear duct
A triangular space bordered by the basilar
membrane, Reissner's membrane, and the
lateral cochlear wall
collecting vein
same as central vein
cochlear nerve
the auditory portion of the vestibulocochlear nerve (CN VIII)
colloid
gel-like material of the follicles; site of
thyroglobulin storage
collagen bundle
a large grouping of collagen fibers
columnar epithelial cell
a cell which is taller than it is wide; lines
large glands and ducts; ideal for absorptive epithelia
collagen fiber
see collagen
collagen fibril
the basic functional and structural unit of
collagen fibers consisting of a repeating
pattern of collagen molecules in a banded
array
common bile duct
structure which drains the cystic and hepatic duct into the duodenum
compact bone
bone characterized by heavy matrix deposition; confers great tensile strength; also
known as 'cortical' bone
collagen
a triple helix protein which allows for
great tensile strength; types include:
11
conducting portion
structures of the respiratory system which
bring air to the sites of gas exchange; include:
•
nasal cavity
•
nasopharynx
•
larynx
•
trachea
•
main bronchi
corpus cavernosum
see erectile tissue
corpus luteum
after ovulation, the collapsed Graafian follicle gives rise to this endocrine structure;
produces progesterone and estrogen
•
Photomicrograph of corpus luteum
cone
photoreceptor cell responsible for color
vision
corpus spongiosum
see erectile tissue
cortex
1) the outer layer of the lymph node and
thymus; contains high concentration of
lymphocytes
•
Photomicrograph of thymus cortex
2) the outer portion of a given organ
•
Photomicrograph of lymph node
cortex
3) the outer portion of the adrenal gland;
comprised of the (outer to inner):
•
zona fasiculata
•
zona glomerulosa
•
zona reticularis
o
Photomicrograph of adrenal
cortex
conjunctiva
mucus membrane lining the space between inner eyelids and surface lateral to
the cornea
connective tissue
supportive tissue; includes:
•
loose connective tissue and dense
connective tissue
•
specialized
connective
tissue:
blood, bone cartilage, lymphatic tissue
•
embryonic tissue: mesenchyme,
mucous connective tissue
continuous capillary
capillaries with a continuous endothelium;
present in muscle, lung, and the CNS
cortical labyrinth
the combination of the renal corpuscle, the
proximal and distal tubules
•
Photomicrograph of cortical labyrinth
cornea
chief refractive element and anterior window of the eye
cortical sinus
also known as "subcapsular sinus"; area
under the capsule where the afferent lymphatic vessels drain; lined by myoepithelial cells
•
Photomicrograph of cortical sinus
•
Photomicrograph of cortical sinus
•
Photomicrograph of cortical sinus
coronary artery
a vessel that brings blood to heart tissue
coronary vein
a vessel that takes deoxygenated blood
away from heart tissue
corpus albicans
a degenerated corpus luteum; filled with
lipid and hyaline
•
Photomicrograph of corpus albicans
corticotrope
cell of the pituitary which stimulates release of hormones by the adrenal cortex
12
crypt
area of the tonsil that contains large
amounts of lymphocytes
dendrite
the signal receiving appendage of neurons
crypt of Lieberkuhn
mucous gland of the intestinal mucosa
•
Photomicrograph of crypt of Lieberkuhn
dense irregular connective tissue
connective tissue with randomized arrangement of abundant collagen fibers and
sparse cellular content (i.e. submucosa)
•
Photomicrograph of dense irregular
connective tissue
cuboidal cell
a cell with even dimensions on all sides;
serves for absorption, barrier, and especially duct-lining
•
Photomicrograph of cuboidal epithelial cell
dense regular connective tissue
connective tissue with ordered and densely packed fibers (i.e. collagen) and cells;
provides significant strength; see also tendon
cytotrophoblast
derivative of the trophoblast (a segment of
the blastocyst which gives rise to the supportive structures of the embryo) that is
mitotically active and fuses with the syncytiotrophoblast
•
Photomicrograph of cytotrophoblast
dermal papillae
connective tissue evaginations from the
dermis into the epidermis
•
Photomicrograph of dermal papillae
dermis
the inner layer of the skin; composed of
dense irregular connective tissue
Descemet's membrane
basal lamina of the corneal endothelium
•
Photomicrograph of Descemet's
membrane
D
desmosome
a strong adhesion on the lateral surfaces of
cells; the strength is imparted by intermediate filament; also known as 'macula adherens'
decidual cell
cells of the endometrial stroma which, under the influence of estrogen and progesterone, store large amounts of glycogen; this
creates a favorable environment for implantation of the blastocyst; appears as
large, pale cell
•
Photomicrograph of decidual cell
diapedesis
process of lymphocyte migration through
the blood vessel lining
diaphysis
the shaft of a long bone
deep cortex
area of the lymph node cortex which is
adjacent to the medulla; T-lymphocytes
are abundant here
dilator pupillae muscle
increases the iris (pupil) opening
13
distal convoluted tubule
a tortuous tubule of the cortex lined by
cuboidal cells; exchanges sodium for potassium, reabsorbs bicarbonate, and converts ammonia to ammonium; houses the
macula densa
•
Photomicrograph of DCT
•
Photomicrograph of DCT
cells of this epithelium possess stereocilia
which move maturing spermatozoa
through the channel
•
Photomicrograph of epididymis
duodenal gland
see Brunner's gland
duodenum
the initial portion of the intestine; receives
contents of the stomach
•
Photomicrograph of duodenum
distal straight tubule
tubule of the medullary ray lined by cuboidal cells
•
Photomicrograph of distal straight
tubule
dust cell
see alveolar macrophage
•
Photomicrograph of dust cell
dome-shaped cell
cell of the bladder which changes shape
according to the state of distension
dorsal surface of the tongue
the top surface of the tongue which is covered with papillae
E
duct
conduit that delivers substances from site
of production to target site; sweat ducts
are typically simple cuboidal epithelium
or stratified cuboidal epithelium
•
Photomicrograph of duct
early spermatid
one of the more mature spermatozoan precursors; it is a round cell that is attached to
the apical membrane of a Sertoli cell
•
Photomicrograph of early spermatid
ductuli efferentes
structure that connects the rete testis to the
ductus epididymis; lined by pseudostratified columnar epithelium
•
Photomicrograph of ductuli efferentes
eccrine sweat gland
sweat gland found all over the body except the lips and external genitalia
•
Photomicrograph of sweat gland
ductus deferens
same as vas deferens; leads from the ductus epididymis to the prostatic urethra;
lined by pseudostratified columnar epithelium
•
Photomicrograph of ductus deferens
efferent arteriole
drainage vessel of the glomerulus
efferent lymph vessel
a vessel that takes lymph away from the
lymph node
ductus epididymis
highly coiled tube lined with pseudostratified columnar epithelium; the principal
ejaculatory duct
14
the ductus deferens and the duct of the
seminal vesicle form this structure in the
body of the prostate gland; empties into
the urethra
in all long bones
endolymph
fluid of the membranous labyrinth of the
inner ear
elastic artery
vessel with dense concentration of elastic
laminae in the tunica media; i.e. aorta
endometrium
lining of the uterus and cervix consisting
of two layers:
•
stratum basale- retained during
menstruation; serves as stem source for
regeneration of the upper stratum functionale
•
stratum functionale- thick part of
endometrium; lost upon menstruation
the uterine lining undergoes changes during the menstrual cycle:
1.
proliferative phase- estrogen regulated; thickening of uterine glands, proliferation of stroma, growth of spiral artery
o
Photomicrograph of proliferative phase
2.
secretory phase- progesterone regulated; very thick endometrium; uterine
glands and spiral arteries coil
o
Photomicrograph of secretory phase
3.
menstrual phase- rupture of vessels;
sloughing of the endometrium; overall
loss in endometrial mass
o
Photomicrograph of menstrual phase
elastic cartilage
see cartilage
elastic cartilage matrix
consists primarily of elastic fibers
elastic fiber
connective tissue fiber that allows for flexibility; composed of the protein elastin
•
Photomicrograph of vestibular
membrane
elastic laminae
elastic fibers arranged in concentric layers:
•
inner elastic lamina- located in tunica intima
•
external elastic lamina- located between tunica media and tunica adventitia
elastin
polypeptide component of elastic fibers
endocardium
the heart wall layer which contacts blood;
consists of outer endothelial layer and inner subendothelial layer of connective tissue
endomysium
connective tissue layer of reticular fibers
surrounding muscle fibers
endoneurium
connective tissue which surrounds individual nerve fibers
endocervix
the part of the cervix facing inward toward
the uterus; see also squamocolumnar junction
•
Photomicrograph of cervix
endosome
membrane-enclosed compartment surrounding a particle/cell that was phagocytosed
endochondral bone formation
a process of bone formation involving a
cartilaginous precursor which is later mineralized and replaced with bone; occurs
endosteum
lining of the bone surface facing the mar15
row and also of trabeculae; consists of osteoprogenitor cells that are referred to as
"endosteal cells"
•
Photomicrograph of endosteum
fied squamous epithelium that comprises
the upper skin layer; extensive keratin deposition allows for effective barrier function; has five strata (from inner to outer):
•
basale- contains stem cells
o
Photomicrograph of stratum
basale
•
spinosum- large cells with ovoid
nuclei
o
Photomicrograph of stratum
spinosum
•
granulosum- cells rich with keratohyalin
o
Photomicrograph of stratum
granulosum
•
lucidum- found in thick skin only;
keratinization is beginning in these cells
o
Photomicrograph of stratum
lucidum
•
corneum- cells without nuclei and
filled with keratin
o
Photomicrograph of stratum
corneum
endotendineum
connective tissue which surrounds a fasicle (the subunit of a tendon); contains
vessels and nerves
endothelial cell
squamous cell that lines blood and lymphatic vessels
•
Photomicrograph of endothelial
cell
•
Photomicrograph of endothelial
cell
endothelium
1)layer of endothelial cells and their underlying basement membrane; lines all but
the
smallest
vessels
2)the deepest layer of the cornea
•
Photomicrograph of corneal endothelium
epimysium
dense connective tissue that surrounds a
group of muscle fiber fascicles (bundles)
entero-endocrine cell
see APUD cell
epinephrine
also known as "adrenaline"; hormone of
the adrenal medulla; involved in the sympathetic response
eosinophil
leukocyte with bilobed nuclei; engages in
phagocytosis of antigen-antibody complex; possesses histaminase and other enzymes which neutralize the substances released by mast cells and basophils to prevent hyperinflammation; bilobed nucleus
(humans); rodent eosinophils have annular
shaped nucleus and monkeys eosinophils
contain multilobed nuclei; have red granules (H&E) in cytoplasm
•
Photomicrograph of eosinophil
•
Photomicrograph of eosinophil
epineurium
connective tissue that binds bundles of
nerve fibers
•
Photomicrograph of epineurium
epiphyseal plate
cartilaginous layer at the epiphysis of long
bones which is the site of longitudinal
bone growth
epicardium
see pericardium
epiphysis
the ends of long bones
epidermis
outer layer of skin; the keratinized strati-
epitendineum
connective tissue layer that surrounds a
16
excretory duct
see duct; in esophagus: lined by stratified
squamous epithelium as it emerges from
the esophageal gland
tendon
epithelioreticular cell
stellate-shaped cell that serves a supportive role in the thymus
•
Photomicrograph of epithelioreticular cell
exocervix
the segment of the cervix facing the vaginal space; see also squamocolumnar
junction
erectile tissue
the corpus cavernosum and the corpus
spongiosum which when engorged with
blood, allow for erection
external anal sphincter muscle
voluntary sphincter of the anus
•
Photomicrograph of external anal
sphincter
ergastoplasm
another name for the rough endoplasmic
reticulum
external elastic lamina
see elastic laminae
erythrocyte
see red blood cell
external elastic membrane
same as external elastic lamina
erythropoiesis
the process of red blood cell formation,
occurs in the bone marrow
external root sheath
outer layer of the hair follicle; derived
from a downgrowth of the epidermis
erythropoietin
a kidney protein which stimulates erythropoeisis in times of reduced tissue oxygen
exudate
debris material containing dead leukocytes
and foreign cells found at sites of infection
esophageal cardiac gland
gland of the terminal esophagus; located
in the lamina propria; secretes a neutral
mucus to protect the esophagus from gastric regurgitation
eyelash
a hair of the eyelid
eyelid
protects the eye from foreign objects and
desiccation
esophageal gland
occurs throughout the esophageal submucosa; secretes a slightly acid secretion
which lubricates the esophageal lumen
estrogen
steroid
hormone
which
maintains/develops female sex characteristics
euchromatin
light-staining matter of the nucleus;
represents less condensed, more actively
transcribed DNA regions
F
17
fibromuscular stroma
dense irregular connective tissue and
smooth muscle of the prostate gland
F-actin
filamentous actin composed of two Gactin (globular actin) strands
filiform papillae
appendages on the dorsal surface of the
tongue; covered with keratinized stratified
squamous epithelium
•
Photomicrograph of filiform papillae
fascia adherens
plates on the transverse intercalated disc
that allow muscle cells to anchor to each
other; analogous to the zonula adherens of
epithelial cells
fimbriae
finger-like extensions of the infundibulum
which catch the oocyte after its departure
from the ovary
fenestrated capillary
capillary with a discontinuous basal lamina as well as gaps (covered by diaphragms) between the endothelial cells
fixed cell
a cell that is a resident of connective tissue; i.e mast cell
fenestrated cortical sinusoidal capillary
see sinusoidal capillary
foam cell
a macrophage containing large lipid
stores; located within an atherosclerotic
plaque
•
Photomicrograph of foam cells
fenestration membrane
a discontinuous basal lamina of a fenestrated capillary covered by a diaphragm
fibroblast
Fusiform cell with cytoplasm that is usually indistinguishable from the surrounding
matrix; tapering processes are present but
are difficult to visualize in most sections;
some very active cells have basophilic cytoplasm; has elliptical nucleus, sometimes
slightly folded, with sparse chromatin that
presents a "speckled" appearance (may be
mistaken for plasma cell); has one to two
nucleoli; makes fibers and ground substance
•
Photomicrograph of fibroblast
foliate papillae
appendages of the dorsolateral surface of
the tongue; contain many taste bud
•
Photomicrograph of foliate pupillae
follicle
1) the spherical structure responsible for
hormone production in the thyroid gland
•
Photomicrograph of thyroid follicle
2) see hair follicle
follicle stimulating hormone (FSH)
pituitary hormone which stimulates the
maturation of the ovarian follicle
fibrocartilage
see cartilage
follicular cell
the cuboidal cell of the thyroid follicle or
the developing follicle
•
Photomicrograph of thyroid follicular cell
•
Photomicrograph of ovarian follicular cell
fibrocartilaginous callus
a stage of bone repair in which fibrocartilage is deposited to stabilize the ends of
the fractured bones; later replaced by the
bony callus
18
folliculogenesis
the process of follicular development; includes several stages (in the following order):
•
primordial follicle- oocyte surrounded by flattened follicular cells
o
Photomicrograph of primordial follicle
o
Photomicrograph of primordial follicle
•
primary follicle- oocyte surrounded
by cuboidal cells
o
Photomicrograph of primary
follicle
•
secondary follicle- theca interna,
theca externa, and antrum present
o
Photomicrograph of secondary follicle
•
Graafian follicle- mature follicle;
all structures of secondary follicle plus a
cumulus oophorus surrounding the oocyte
o
Photomicrograph of Graafian follicle
G-actin
"globular" actin, appears bead-like in
structure
GALT
Gut Associated Lymphatic Tissue; lymphatic aggregates located throughout the
digestive tract
ganglion
a group of neuronal cell bodies
•
Photomicrograph of sympathetic
ganglion
ganglion cell
1) a cell of a ganglion 2) postganlionic cell
of the adrenal medulla; causes release of
norepinephrine and epinephrine upon
nervous stimulation
•
Photomicrograph of ganglion cell
•
Photomicrograph of ganglion cell
fundic gland
simple, branched tubular gland of the stomach fundus that produces the substances
necessary for digestion; contains Chief
cells, mucous neck cells, parietal cells,
APUD cells, and stem cells
ganglion cell layer
layer of the neural retina which houses
neurons involved in transmitting the signals of photoreception
gap junction
channel that allows electrical, electrolyte,
and fluid communication between adjacent cells; also known as nexus
fungiform papillae
mushroom-shaped appendages of the dorsal tongue; contain numerous taste buds
gastric gland
another name for fundic glands
gastric pit
depression of the stomach lining that
opens into the gastric gland
germinal center
area of lymphatic tissue containing rapidly
developing/differentiating lymphocytes
•
Photomicrograph of germinal center
G
19
germinal epithelium
cuboidal cells that line the surface of the
ovary; does NOT give rise to germ cells
Graafian follicle
see folliculogenesis
granulocyte
neutrophils, eosinophils, and basophils, all
of which possess certain immunoreactive
substances contained in granules
gland
structure involved in producing substances
to be secreted; sweat glands tend to be
lined by either stratified cuboidal epithelium or stratified columnar_epithelium
granulopoiesis
the developmental process of granulocytes
glomerular basement membrane
GBM; basal lamina between the podocytes and endothelium; allows selective
permeability by size and charge (positive,
small particles filter easier
granulosa cell
cell which comprises a layer which surrounds the antrum of the mature follicle;
catalyzes the conversion of androgens to
estrogen
•
Photomicrograph of granulosa cell
glomerulus
capillary meshwork of the kidney nephron
granulosa lutein cell
cell of the corpus luteum derived from the
granulosa cell
•
Photomicrograph of granulosa lutein cell
glucocorticoid
see zona fasciculata
glycogen
primary energy storage form of animal
cells; appear as empty vacuoles in LM
ground substance
viscous substance that occupies the space
between fibroblasts and connective tissue
goblet cell
special mucus-secreting columnar epithelial cell located in the respiratory system and intestines; large vacuoles can be
seen in light microscopy
•
Photomicrograph of goblet cell
H
Golgi complex
cellular structure involved in modifying,
packaging, sorting, and secreting proteins;
has cis face for receiving and trans face
for releasing products
•
Photomicrograph of Golgi complex
H band
a region of the sarcomere with only myosin filaments; shortens with contraction
gonadocorticoid
LH and FSH; released by the gonadotropes
hair
appendage of the skin composed of keratinized cells
gonadotrope
cell of the adenohypophysis which releases LH and FSH
hair cell
20
the cell of audioreception protruding from
the basilar membrane; registers vibration,
which is then converted to electrical signals transmitted along the cochlear nerve
hemopoiesis
process of blood cell formation from a
common stem cell; occurs in bone marrow
in the adult
hair follicle
skin structure from which hairs arise
hemosiderin
debris found in heart failure cells
•
Photomicrograph of hemosiderin in
a dust cell
Hassall's corpuscle
concentric arrangement of epithelioreticular cells; more prominent in adults
•
Photomicrograph of Hassal's corpuscle
•
Photomicrograph
of
Hassal's
cprpuscle
Haversian canal
see Haversian system
•
Photomicrograph
canal
of
hepatic acinus
see liver acinus
hepatic artery
vessel carrying oxygen rich blood to the
liver
•
Photomicrograph of hepatic artery
•
Photomicrograph of hepatic artery
Haversian
hepatic duct
duct which delivers bile from the liver to
the cystic and common bile ducts
Haversian system
concentric lamellae arranged around a
central (Haversian) canal which conatins
blood vessels and nerve supply
hepatic sinusoid
sinusoids of the liver
•
Photomicrograph of hepatic sinusoid
•
Photomicrograph of hepatic sinusoid
heart failure cell
alveolar macrophage filled with hemosiderin; indicative of congestive heart failure
helper T-lymphocyte
a cell that stimulates B-lymphocytes and
T-lymphocytes to carry out their respective functions
hepatic vein
drains deoxygenated blood from the liver
to the inferior vena cava
hematopoiesis
same as hemopoiesis
hepatocyte
the basic functional cell of the liver
•
Photomicrograph of hepatocyte
hemidesmosome
structure on the basal surface of an epithelial cell that anchors it to connective
tissue elements
Herring body
axonal dilation within the neurons of the
pars nervosa; contains either oxytocin or
vasopressin
•
Photomicrograph of Herring body
hemocytoblast
large cell with basophilic cytoplasm and
large nucleus which was at one time considered to be the precursor to all blood cell
types
heterochromatin
dark staining regions of chromatin in the
nucleus; signifies DNA regions of little
21
I
transcripitional activity
hilus
the area of a lymph node where vessels
enter and exit
Hofbauer cell
macrophage-like cell of the chorionic villus; unknown function; contains stores of
lipids and glycoproteins
•
Photomicrograph of Hofbauer cell
I band
a region of the sarcomere whose span includes only actin filaments
•
Photomicrograph of I band
holocrine
mode of secretion in which part of the secretory cell is exuded in the product; i.e.
sebaceous gland
ileum
terminal portion of small intestine; opens
into cecum of the large intestine
immunoglobulin
antibody secreted by the plasma cells;
types include:
•
IgA- present in body secretions
•
IgD- on the surface of lymphocytes
and is involved in their differentiation
•
IgE- stimulates mast cells to release
immunoreactive substances
•
IgG- activates complements, which
lyse bacteria; elemental in secondary response and passive immunity
•
IgM- activates macrophages; activates complements; primary Ig of primary
response
Howship's lacuna
the space underneath an osteoclast where
bone matrix is being resorped
hyaline cartilage
see cartilage
hypertrophy
overgrowth of cells due to: overstimulation of the tissue/organ which they comprise, a cancer, or a benign condition such
as BPH (benign prostratic hypertrophy)
hypodermis
a layer of connective tissue beneath the
dermis; contains ample adipose
inactive mammary gland
mammary gland with much dense irregular connective tissue and no secretory activity
•
Photomicrograph
of
inactive
mammary gland
hypophyseal portal system
capillary network carrying neuroendocrine
secretions from the median eminence and
infundibular stem to the pars anterior
inflammation
bodily response to injury characterized by
pain, swelling, redness, and loss of function; triggered by heavy infiltration of leukocytes, particularly neutrophils
hypothalamohypophyseal tract
nerve tract leading from the hypothalamus
to the pituitary
infundibulum
1)attachment between the hypothalamus
and
pituitary
2)see oviduct
22
tery and descends into a kidney lobule; a
lobule is a segment of a lobe, which in
turn consists of a pyramid and surrounding
tissue on its base and sides
•
Photomicrograph of interlobular
artery
inner circumferential lamellae
concentric rings of bone matrix closer to
the bone center
inner elastic membrane
same as internal elastic lamina
interlobular duct
duct of the mammary gland; located at a
distance from lobules
inner limiting membrane
layer of the neural retina composed of the
basal lamina of Muller cells
interlobular vein
vessel that carries deoxygenated blood in
the same region as the interlobular artery,
but in reverse course
•
Photomicrograph of interlobular
vein
inner nuclear layer
layer of neural retina housing horizontal,
amacrine, bipolar and Muller cells
inner plexiform layer
contains processes of the cells of the inner
nuclear layer
intermediate filament
cytoskeletal element which serves a general supportive and structural function
intercalated disc
structure which connects adjacent muscle
fibers at their ends; also allows for communication via gap junctions which span it
•
Photomicrograph of intercalated
disc
intermediate lobe
see pars intermedia
internal anal sphincter muscle
the involuntary, inner anal sphincter;
composed of smooth muscle
•
Photomicrograph of internal anal
sphincter
intercalated duct
located between an acinus and larger ducts
in salivary glands; secrete bicarbonate and
absorb chloride; most prominent in salivary glands that produce watery secretions
•
Photomicrograph of intercalated
duct
internal elastic lamina
see elastic laminae
internal elastic membrane
same as internal elastic lamina
intercellular bridge
the actin filament bundles interposed between adjacent Sertoli cells
interstitial growth
process of bone/cartilage growth due to
cell division rather than matrix deposition
intercellular space
a space between adjacent cells
interstitial lamellae
rows of bony matrix in the area between
Haversian systems
•
Photomicrograph of interstitial lamellae
interlobar artery
branch of the renal artery; travels between
adjacent renal pyramids
interlobular artery
vessel that branches from an interlobar ar-
interterritorial matrix
23
in cartilage, material at a distance from
cells; proteoglycans are in sparse concentration here; see also territorial matrix
islet of Langerhans
functional unit of the endocrine pancreas;
composed of three cell types:
•
A cells- secrete glucagon
•
B cells- secrete insulin
•
D cells- secrete somatostatin
•
Photomicrograph of islet
intervillous space
see chorionic villus
intestinal gland
same as crypt of Lieberkuhn
isogenous group
group of contiguous chondrocytes that results from the division of a single precursor
intracellular canaliculus
invagination of the parietal cell membrane
with numerous microvilli; this system enhances the surface area available for HCL
release
isthmus
see oviduct
intralobular duct
1) the equivalent of the striated duct; lined
by cuboidal cells; functions in reabsorption of sodium and secretion of potassium;
found in salivary glands and the pancreas
•
Photomicrograph of intralobular
duct
2) duct leading from the mammary lobules
to the interlobular duct
Ito cell
see lipocyte
J
intramembranous bone formation
process in which bone is laid down by osteoblasts without a prior cartilaginous precursor; primary mode of flat bone formation
•
Photomicrograph of intramembranous bone formation
jejunum
middle portion of the small intestine
junctional complex
the combination of desmosomes, zonula
adherens, and zonula occludens
intrinsic striated muscles of tongue
visceral striated muscle; allow for voluntary tongue movement
juxtaglomerular apparatus
structure adjacent to the afferent and efferent arterioles; it is involved in the release
of renin, and hence the control of blood
pressure; consists of:
•
juxtaglomerular cells (modified
smooth muscle cells containing renin granules)
•
the macula densa
•
extraglomerular mesangial cells
iridocorneal angle
the space between where the iris and cornea are anchored
iris
diaphragm extending over the lens surface; controls pupil diameter
islet cell
see islet of Langerhans
24
juxtaglomerular cell
see juxtaglomerular apparatus
labial mucosa
lining of the oral surface of the lip; consists of stratified squamous nonkeratinized epithelium
lacteal
a small lymphatic vessel located at the intestinal villus tip
K
lacuna
the housing compartment of chondrocytes
and osteocytes within their respective matrices
•
Photomicrograph of lacuna
keratinized stratified squamous epithelium
see epidermis
lamina propria
the loose connective tissue of mucous
membranes
keratinocyte
cell of the epidermis which produces keratin
Langerhans cell
antigen-presenting cell of the stratum spinosum; has clear cytoplasm and darkstaining nucleus
keratohyalin
protein produced by the keratinocyte
which becomes keratin when combined
with tonofilaments (intermediate filaments)
larynx
air passage between the oropharynx and
the trachea
killer T-lymphocyte
a cell of the immune system that directly
attacks foreign cells, causing lysis
late spermatid
elongate spermatozoan precursor bordering the seminiferous tubule lumen, yet still
attached to a Sertoli cell
•
Photomicrograph of late spermatid
Kupffer cell
cell of the mononuclear phagocytic system
which resides in the space of Disse; degrades damaged erythrocytes
•
Photomicrograph of Kupffer cell
lateral surface of epithelial cell
that side of the cell in contact with other
cells; usually anchored by various filament complexes
layer of rods and cones
layer of neural retina housing the photoreceptors
L
lens
transparent, elliptical structure which
along with the cornea, is a refractive element of the eye
•
Photomicrograph of lens epithe25
lipofuscin
vacuole containing debris; the older a cell,
the more lipofuscin it will contain; also
known as tertiary lysosome and residual
body
lium
lens capsule
thick basal lamina covering the lens
leukemia
a cancer in which the numbers of leukocytes in the blood increase dramatically;
immature blood cells are also found in circulation in this condition
liver acinus
elliptical model of liver organization with
central veins on the ends of the long axis,
and portal triads on the ends of the short
longitudinal axis
leukocyte
a cell of the immune system; also known
as a white blood cell
lobe
subdivision of the lung; the left lung is divided into an upper and lower lobe, the
right lung is divided into an upper, middle,
and lower lobe
leutinizing hormone
pituitary hormone which stimulates theca
interna cells to secrete androgens
lobule
1)a group of ducts and surrounding connective tissue within the mammary gland
2)the functional unit of liver organization;
defined variously as: the classical lobule,
the liver acinus, and the portal lobule
3)an area of the lung supplied by a bronchiole
Leydig cell
cell of the stroma surrounding the seminiferous tubule which produces testosterone;
this hormone is important in the male for:
•
differentiation of CNS and genitalia
•
development of secondary sex characteristics
•
libido development
•
anabolic processes
o
Photomicrograph of Leydig
cell
longitudinal (meridional) fiber
part of the ciliary muscle; causes tension
of the lens
limbus
a transitional area between cornea and
sclera
loop of Henle
a U-shaped structure of the nephron consisting of the descending proximal straight
tubule, the thin segment, and the ascending distal straight tubule
lipid
fatty acids, cholesterol, etc. housed in cells
as vacuoles
loose connective tissue
connective tissue with an abundance of
cells and sparse fibers
•
Photomicrograph of loose connective tissue
lipid droplet
lipid vacuoles inside cells; usually lost in
preparation for microscopy
lipocyte
also known as "Ito cell"; cell of the liver
which stores large amounts of lipid as well
as vitamin A
lymph nodule
aggregates of lymphocytes in the cortex of
the lymph node
lymphatic channel
26
same as lymphatic vessel
each other
lymphatic vessel
a vessel that carries lymph, which consists
of interstitial fluid, cells of the immune
system, foreign cells, and other substances
•
Photomicrograph of lymphatic vessel
macrophage
massive cell involved in phagocytosis of
foreign material or defective host cells,
and in antigen presentation; usually irregular in shape with vacuolated cytoplasm;
the macrophage is difficult to distinguish
from a fibroblast without the presence of
phagocytosed material
•
Photomicrograph of macrophage
•
Photomicrograph of macrophage
•
Photomicrograph of macrophage
lymphocyte
Small round cell with dark nucleus and
only a thin rim of cytoplasm:
•
B-lymphocytes- involved in humoral response
•
T-lymphocytes- involved in cellmediated response
o
Photomicrograph of lymphocyte
o
Photomicrograph of lymphocyte
macula adherens
see desmosome
macula densa
specialized cell group of the distal convoluted tubule that is part of the juxtaglomerular apparatus
•
Photomicrograph of macula densa
lymphopoiesis
the process of development of lymphocytes in lymph nodes
malignant acinus
in prostate cancer, the presence of glandular hypertrophy
•
Photomicrograph of prostate cancer
lysosome
digestive organelles containing various
hydrolytic enzymes;
•
Primary- newly formed as a bud
from the Golgi
•
Secondary- primary lysosome
fused to target material
•
Tertiary- vacuole containing remnants of the digestive process; also called
"residual body"
Mallory body
eosinophilic inclusion found in the hepatocyte of alcoholics
•
Photomicrograph of Mallory body
MALT
mucosa associated lymphatic tissue; lymphatic aggregates of the cervical mucosa
mammatrope
acidophilic cell of the adenohypophysis
which releases luteotropic hormone (LTH)
M
marginal zone
area between the red pulp and white pulp
of the spleen
M band
located in the sarcomere, a region at the
center of the H band which signifies the
attachment sites of myosin filaments to
marrow
see bone marrow
27
mast cell
large fixed cell that has large granules
containing immunoreactive and vasoactive
substances: histamine, slow-reacting substance of anaphylaxis, eosinophilic chemotactic factor of anaphylaxis, and heparin; found near blood vessels; round small
nucleus (as compared to cell size); numerous granules show metachromasia with
some stains
•
Photomicrograph of mast cell
medullary ray
aggregate of the proximal, distal straight
and collecting tubules
•
Photomicrograph of medullary ray
medullary sinus
space between adjacent medullary cord;
drains lymph into the efferent lymph vessel
•
Photomicrograph of medullary sinus
mature cell
a cell after it has fully developed from its
precursors; if applied to granulocytes, refers to the cell form of the circulation,
which usually contains a multilobed segmented nucleus
medullary vein
also known as "central vein"; large, muscular vein of the adrenal medulla; its
strong contractility facilitates quick release of the medullary hormones
megakaryocyte
a massive precursor of platelets within the
bone marrow; possesses a multilobed nucleus
•
Photomicrograph of megakaryocyte
median eminence
continuous with the infundibulum; carries
neurosecretory nerves
mediastinum testis
connective tissue that projects into the parenchyma of the testis, carrying with it
blood and lymph vessels
meiosis
a process which produces daughter cells
with half the DNA content of the parent;
results in germ cell production
medulla
the inner portion of an organ; in the thymus and lymph node, area of relatively
sparse lymphocyte concentration
•
Photomicrograph of thymus medulla
Meissner's corpuscle
receptors of low frequency tactile stimuli;
located on hairless skin
•
Photomicrograph of Meissner's
corpuscle
medulla of lymph node
inner portion which contains a lesser concentration of lymphocytes
•
Photomicrograph of medulla
•
Photomicrograph of medulla
Meissner's plexus
a ganglion of the submucosa which controls secretion in the digestive tract
melanocyte
a cell of the epidermis which produces
melanin, the substance responsible for
pigmentation
•
Photomicrograph of melanocyte
medullary cord
tissue of the medulla in lymph organs containing reticular cells, lymphocytes, macrophages, and plasma cells
•
Photomicrograph of lymph node
medullary cord
melanotrope
cell of the pars intermedia which stimulates melanin production; found in some
28
non-human species
metaphysis
the curve between the ends of the bone
(epiphysis) and the shaft of the bone
(diaphysis)
membrane coating granule
found within the keratinocytes of the stratum spinosum; contains a glycolipid that
forms a water barrier on the skin surface
metastasis
the spread of a cancer to areas away from
where it originated
menstrual phase of the endometrium
see endometrium
Merkel cell
cell of stratum basale which functions in
cutaneous sensation
metastatic cancer cell
cell involved in metastasis
microbiological flora
bacteria; found in certain body cavities;
see Pap smear
mesangial cell
cell of the juxtaglomerular apparatus and
renal corpuscle; involved in phagocytosis
of debris
•
Photomicrograph of mesangial cell
mesaxon
slit left exposed on outer myelin sheath
after myelin wrapping is complete
microfilament
cytoskeletal element involved in cell anchorage,
contraction,
exocytosis/endocytosis, structure of microvilli,
and locomotion; actin and myosin are examples
mesothelial cell
squamous cell comprising the cellular part
of the mesothelium
•
Photomicrograph of mesothelial
cell
microtubule
cytoskeletal element found in cilia, flagella, basal bodies, the mitotic spindle, centrioles, cytoplasm, and elongating cell
processes (i.e. axon)
mesothelium
epithelial lining of the body cavities (i.e.
thoracic, pericardial, abdominal)
microvilli
processes of the apical plasma membrane
of absorptive cells; increase surface area
for absorption
metachromasia
phenomenon in which a basic dye changes
color from blue to red/purple due to the
dense presence of polyanionic groups (i.e.
phosphates, sulfates)
mineralocorticoids
see zona glomerulosa
minor calyx
the point where the collecting ducts of a
pyramid drain; several of these structures
drain into a major calyx
metamyelocyte
precursor of granulocytes which shows
varying degrees of indentation, and elongation of the nucleus indicative of differentiation into the more mature juvenile or
band forms.
•
Photomicrograph of metamyelocyte
(neutrophilic)
mitochondria
oxidative organelle of the cell; believed to
be derived from a prokaryotic symbiote
mitochondrial cristae
29
involutions of the inner mitochondrial
membrane protruding into the matrix; contain enzymes of oxidative phosphorylation
mucous acinus
a mucous secretory unit with a circular
arrangement of mucous cells
•
Photomicrograph of mucous acinus
mitosis
process which produces two daughter
cells, each with genetic material equal in
amount to the parent
mucous cell
a cell that produces and releases mucous;
vacuoles are usually visible within the eosiniphilic cytoplasm
mitotic cell
cell in the process of dividing into two
daughter cells which will contain the same
amount of genetic material as the parent
mucous gland cell
a cell of a mucous gland located in the digestive tract, respiratory system, etc
mixed spicule
newly forming bone atop calcified cartilage; seen in endochondral bone formation
mucous gland
a gland that release mucous, a glycoprotein
modiolus
bony core around which the cochlea turns
2 and 3/4 times
mucous neck cell
located at the neck of the fundic gland;
secretes a soluble mucous
monoblast
precursor of the promonocyte
mucous-secreting cell
see mucous cell
monocyte
the large blood-borne precursor of mononuclear phagocytic system cells; has some
vacuoles and indented nucleus frequently
lacking nucleoli
•
Photomicrograph of monocyte
mucous surface cell
cell lining the gastric pit; secretes an insoluble mucous
muscle fiber
see myofiber
mononuclear phagocytic system
cells capable of vigorous phagocytosis;
arise from monocytes; this system includes:
•
macrophages
•
Kupffer cells
•
osteoclasts
•
Langerhans cell
muscular artery
most numerous of artery types; notable for
thick, muscular tunica media; example is
brachial artery
•
Photomicrograph of muscular artery
muscularis
see muscularis externa
mucocutaneous junction
the border between the epidermis of the
outer lip and the labial mucosa
muscularis externa
located beneath the submucosa of the esophagus; consists of an inner circular and
outer longitudinal layer
mucosa
the combination of an epithelial lining, the
lamina propria, and muscularis muscosae
30
muscularis mucosa
deepest layer of the mucosa; consists of an
inner circular and outer longitudinal layer
•
Photomicrograph of muscularis
mucosa
contractile cell that lines glands; it contracts to cause secretion; i.e. the alveoli of
the mammary gland are lined by these
cells
•
Photomicrograph of myoepithelial
cell
myelin
lipid-rich substance that is formed as a
sheath by Schwann cells onto certain types
of nerves; allows for rapid conduction
•
Photomicrograph of myelinated
nerve
•
Photomicrograph of unmyelinated
nerve
myofiber
also known as "myotube"; the muscle cell
•
Photomicrograph of vestibular
membrane
myofibril
a unit of repeating sarcomeres; subunit of
the myofiber
myelin sheath
see myelin
•
Photomicrograph of myelin sheath
myofibroblast
spindle-shaped cell that displays cytological characteristics of both fibroblasts and
smooth muscle cells; elongated nucleus
often exhibits an wavily profile; cytoplasm can be distinguished from the surrounding matrix due to the presents of actin filaments (and dense bodies at EMlevel); does not have basal (external) lamina; is seen usually as an isolated cell,
although its processes may contact the
processes of other myofibroblast (gap
junctions at EM-level); contractile cell of
connective tissue; major role in wound
contraction
myelinated axon
see myelin
myelinated nerve
see myelin
myeloblast
precursor of the promyelocyte; have large
nuclei
myelocyte
precursor in the granulocyte cell line; first
one to contain specific granules; has
slightly indented nucleus; also a reduction
in the number of the azurophilic granules;
cells are further distinguished according to
the type ofgranules that develop, i.e., neutrophilic myelocyte (60%), eosinophilic
myelocyte, basophilic myelocyte (3%);
the nucleus of these cells is slightly indented; cells in this series divide and give
rise to metamyelocytes
•
Photomicrograph of myelocyte
myofilament
functional and structural protein of muscle
cells; see actin and myosin
myoid cell
a cell of the stroma surrounding the seminiferous tubule; has contractile properties
and also secretes the stroma matter
•
Photomicrograph of myoid cell
•
Photomicrograph of myoid cell
myocardium
intermediate, bulky layer of the heart wall;
comprised of numerous cardiac myocytes
myometrium
smooth muscle layer of the uterus
myosin
thick filament constituent protein which
myoepithelial cell
31
together with actin allows for muscle contraction
neurofilament
intermediate filament located in axons
function in axonal transport
myotube
see myofiber
neurohypophysis
posterior pituitary; contains neurosecretory tissue
myotube nucleus
nucleus of a myofiber
neuron
the nerve cell; allows for conduction and
reception via specialized processes (axons
and dendrites)
N
neutrophil
also known as "polymorphonuclear leukocyte"; a leukocyte which engages actively
in phagocytosis and is the main trigger for
the inflammation response; multilobed
nucleus with heterochromatin and no visible nucleolus; some granules in cytoplasm
may stain light blue to pink depending on
conditions
•
Photomicrograph of neutrophil
•
Photomicrograph of neutrophil
neck of gastric gland
see mucous neck cell
nephron
functional unit of the kidney; consists of a
glomerulus and its tubular network
•
cortical nephron- has renal corpuscles in the outer cortex; has short loops of
Henle
•
juxtamedullary nephron- has renal
corpuscle near the base of a pyramid; has
long loops of Henle
Nissl body
rough endoplasmic reticulum (rER) of the
nerve cell
node of Ranvier
space between two adjacent Schwann cells
which is a gap in the myelin sheath; allows for a jumping signal known as "saltatory conduction"
•
Photomicrograph of node of Ranvier
•
Photomicrograph of node of Ranvier
nerve
see nerve fiber
nerve fiber
structure comprised of the axon and its
myelin sheath; a bundle of nerve fibers
forms a nerve, which serves as a "cable"
to
communicate
electrical
signals
throughout the body
•
Photomicrograph of vestibular
membrane
nonciliated cell
those cells lacking cilia; see also oviduct
non-keratinized stratified squamous epithelium
see stratified squamous non-keratinized
epithelium
nervi vasorum
nerve supply to vessels; located in the tunica adventitia
32
non-myelinated axon
see myelin
smell in the nasal cavity
olfactory epithelium
epithelium responsible for the sense of
smell; consists of:
•
olfactory cells
•
sustentacular cells
•
basal cells
•
brush cells
norepinephrine
also referred to as "noradrenaline"; hormone of the adrenal medulla involved in
the sympathetic response
normoblast
also known as "orthochromatophilic erythroblast"; erythrocyte precursor with
heavy eosinophilic stain due to dense hemoglobin production
•
Photomicrograph of normoblast
oocyte
the developing female gamete
oogenesis
production of oocytes
nuclear envelope
the membrane surrounding the nucleus;
continuous with the rough endoplasmic
reticulum
oogonia
cells which give rise to primordial follicles
open circulation theory
model in which blood empties from splenic arterioles into the splenic cords and
from there into the splenic sinuses
nuclear pore
opening in nuclear envelope which allows
for transit of ribosomal subunits, mRNA,
etc.
optic nerve fiber layer
layer of the neural retina containing the
axons of the ganglion cells
•
Photomicrograph of optic nerve
nucleolus
site of ribosomal RNA synthesis; appears
as dense structure within the nucleus
•
Photomicrograph of nucleolus
oral mucosa
see labial mucosa
nucleus
enveloped compartment containing the
genetic material of the cell
•
Photomicrograph of nucleus
orbicularis oculi muscle
voluntary muscle which allows for eyelid
closure
nucleus of ganglion cell
see nucleus
orbicularis oris muscle
striated, voluntary muscle of the lip
organ
a structure that performs a specific function (i.e. digestive action of stomach)
O
organ of Corti
consists of hair cells and supporting cells
atop the basilar membrane; it is the site of
aufioreception when hair cells are stimulated by vibrations
olfactory cell
bipolar neurons that are the receptorsof
33
•
Photomicrograph of organ of Corti
layer of the neural retina housing the cell
bodies of rods and cones
osteoblast
a flat, eosinophilic cell which secretes
bone matrix
•
Photomicrograph of osteoblast
outer plexiform layer
layer of the neural retina containing the
processes of rods, cones, bipolar, horizontal, and amacrine cells
osteoclast
a phagocytic cell involved in the resorption of bone matrix
•
Photomicrograph of osteoclast
ovarian cyst
structure seen in polycystic ovarian disease (PCOD); lined by granulosa cells and
surrounded by hypertrophic theca interna
cells
•
Photomicrograph of ovarian cyst
osteocyte
a mature osteoblast; has an ovoid shape
•
Photomicrograph of osteocyte
ovarian stroma
the supporting tissue of the ovary; contains much loose connective tissue, blood
vessels, lymphatic vessels, and nerves
osteoid
unmineralized bone matrix secreted by
osteoblasts
•
Photomicrograph of osteoid
oviduct
lined by ciliated cells and nonciliated
("peg") cells; tube leading from the ovary
to the uterus; has four parts:
•
infundibulum- segment closest to
ovary; its fimbriae catch the oocyte
•
ampulla- longest segment; site of
fertilization
•
isthmus- narrow segment next to
the uterus
•
intramural part- opens into the uterine cavity
o
Photomicrograph of oviduct
o
Photomicrograph of "peg
cell"
osteon
see Haversian system
osteoprogenitor cell
cell contained in the periosteum, the fibrous layer which covers bone; gives rise to
osteoblasts
•
Photomicrograph of osteoprogenitor cell
outer circumferential lamellae
concentric rings of bony matrix closer to
the bone periphery than the center
outer cortex
the outer portion of the lymph node cortex
containing nodules, which in turn house
germinal centers
ovulation
the process of oocyte release from the
Graafian follicle; occurs due to a sharp
rise in leutinizing hormone (LH)
outer elastic membrane
see elastic laminae
oxyphil
round, acidophilic cell of the parathyroid
with no known function
•
Photomicrograph of oxyphil
outer limiting membrane
layer between the layer of rods and cones
and the outer nuclear layer
outer nuclear layer
34
cell
P
parakeratinized epithelium
epithelium of the mucocutaneous junction;
analogous to the epidermis but with a top
layer of cells that retain their nuclei
•
Photomicrograph of parakeratinized epithelium (lip)
Pacinian corpuscle
pressure receptor of the skin located in the
dermis and hypodermis
•
Photomicrograph of Pacinian corpuscle
parakeratosis
disease state signified by retention of nuclei in the cells of the stratum corneum
parathyroid gland
ovoid gland associated with the thyroid
gland; produces parathyroid hormone necessary for phosphate and calcium regulation
•
Photomicrograph of parathyroid
gland
pampiniform plexus
unusually thick veins of the spermatic
cord; have at least two smooth muscle
layers
•
Photomicrograph of vein of pampiniform
parenchyma
the functional tissue of an organ; as opposed to its supportive elements (i.e. the
stroma
pancreatic acinar cell
secretory cell of the pancreas; contain granules visible under LM
pancreatic acinus
circular secretory unit of the exocrine pancreas
parenchymal cell
any cell involved in the basic function(s)
of a given tissue, i.e. hepatocyte of the liver
Paneth cell
specialized cell of the the small intestine
that releases antibacterial substances and
engages in phagocytosis; regulates the
small intestinal flora population
•
Photomicrograph of Paneth cell
parietal cell
cell of the fundic gland that releases HCL
and intrinsic factor
•
Photomicrograph of parietal cell
parietal layer of Bowman's capsule
outer layer of the capsule; consists of
squamous cells
Pap smear
cytological exam conducted by scraping
the vaginal and cervical lining; contains
epithelial cells, granulocytes, microbiological flora, erythrocytes, and lymphocytes;
may on occasion contain cancer cells
parotid gland
a serous gland of the oral cavity
•
Photomicrograph of parotid gland
pars anterior
also known as "pars distalis"; the main secretory portion of the adenohypophysis;
three cell types within it are
parafollicular cell
cell located between thyroid follicles; secretes calcitonin
•
Photomicrograph of parafollicular
35
•
•
•
acidophils
basophils
chromophobes
serosa of the uterus
perimysium
connective tissue that surrounds a group of
muscle fibers to form a fasicle
pars intermedia
part of the adenohypophysis with unknown function; secretes MSH in certain
species
perineurial cell
a cell of the perineurium; has contractile
property
pars nervosa
part of the neurohypophysis which has
neurosecretory nerve endings
perineurium
connective tissue which surrounds a nerve
fiber bundle
pars tuberalis
part of the adenohypophysis which encircles the pars intermedia
periosteum
dense connective tissue layer that surrounds bone; contains osteoprogenitor
cells
•
Photomicrograph of periosteum
penicillar artery
branch of the central artery of the spleen
as it enters the red pulp
peritubular capillary
branch of the efferent arteriole which supplies and exchanges substances with the
tubular network of the nephron
periarterial lymphoid sheath
"PALS"; layer of lymphocytes aggregated
around the central artery of the spleen
pericardium
mesothelial layer surrounding the outer
heart surface; contains vessels and nerves
supplying the heart
peroxisome
oxidative organelle; also known as
'microbody'; contains catalase and other
peroxidases to break down hydrogen peroxidase produced from oxidative
processes
perichondrium
dense irregular connective tissue which
surrounds hyaline cartilage; contains fibroblasts and chondroblast precursors
•
Photomicrograph of perichondrium
phagocytosis
active engulfment by a cell of particles or
another cell
pericyte
precursor of smooth muscle cells located
in certain capillaries
pharynx
passage between the nasal and oral cavities and the larynx
perikaryon
the cell body of the neuron
pigmented epithelium
layer of the retina which prevents light
scatter
perilymph
fluid between the bony and membranous
labyrinth
pituicyte
cell of the neurohypophysis which may
play a supportive role to the neurons located in that structure
perimetrium
36
•
Photomicrograph of pituicyte
polychromatophilic erythrocyte
small, basophilic, enucleated cell which is
the immediate precursor of the erythrocyte
•
Photomicrograph of polychromatophilic erythrocyte
plasma cell
derivatives of B-lymphocytes which mass
produce antibodies; eccentrically placed
nucleus with round shape; the distinct pattern or heterochromatin frequently
presents a "cartwheel" appearance; negative Golgi and basophilic cytoplasm are
evident
•
Photomicrograph of plasma cell
portal lobule
triangular model of liver organization with
three central veins surrounding a portal
triad
plasma membrane
semipermeable bilayer which surrounds
cells; consists of phospholipids, proteins
and carbohydrates
portal system of blood flow
a system in which a vein or arteriole is interposed between two capillary beds;
found in the kidney, liver, and piutitary
platelet
formed element of the blood involved in
clotting
•
Photomicrograph of platelet
portal triad
branches of the hepatic artery, the portal
vein, and the bile duct that run in tandem
within the liver parenchyma
plicae circularis
semicircular folds within the submucosa
of the small intestine; confer an irregular
surface to the inner small intestine; most
numerous in the jejunum
portal vein
a vessel that brings blood from the digestive tract, spleen, and pancreas to the liver
•
Photomicrograph of portal vein
•
Photomicrograph of portal vein
podocyte
cell of the visceral layer of Bowman's capsule; has numerous foot processes which
act as part of the filtration barrier
•
Photomicrograph of podocyte
postcapillary venule
also known as high endothelial vessel
(HEV); vessels with cuboidal lining in the
deep cortex
•
Photomicrograph of HEV
polar body
body of excess cytoplasm produced in the
meiotic division of the oocyte; eventually
degenerate
posterior chamber of eye
space posterior to the iris and anterior to
thelens
posterior lobe
see neurohypophysis
polychromatophilic erythroblast
cell that has cytoplasm that is a dull gray
to gray-green color due to a combination
of basophilic staining (polyribosomes) and
eosinophilic staining (hemoglobin); continued division and maturation gives rise
to normoblasts
•
Photomicrograph of polychromatophilic erythroblast
primary center of ossification
site of initial bone formation inside the
diaphysis
primary follicle
see folliculogenesis
37
primary oocyte
see folliculogenesis
primordial follicle
see folliculogenesis
crease in number of granules and increase
in cell size (24 um) as a result of one or
more divisions, smaller late promyelocytes are produced
•
Photomicrograph of promyelocyte
principal cell
cell of the parathyroid which secretes parathyroid hormone (PTH)
•
Photomicrograph of principal cell
prostate gland
largest accessory sex gland; secretes acid
phosphatase, fibrinolysin, and citric acid;
contains prostatic glands
procollagen
polypeptide which is converted to collagen extracellularly
prostatic concretion
calcified aggregate of the prostate gland
which has "tree ring" like appearance;
found especially in older men
proerythroblast
earliest precursor of erythrocytes; has
large nucleus and basophilic cytoplasm;
13-18 um in diameter; large spherical nucleus with 1-2 distinct nucleoli; thin rim of
slight to moderate basophilic cytoplasm
(basophilia attributable to increasing numbers of free ribosomes; rER absent); divides to give rise to basophilic erythroblast
•
Photomicrograph of proerythroblast
prostatic gland
tubuloalveolar gland that secretes acid
phosphatase, citric acid, and fibrinolysin
into the urethra
prostatic sinus
spaces that open into the prostatic urethra
prostatic urethra
the portion of the urethra within the prostate
proliferative mammary gland
mammary gland consisting of dense concentration of secretory structures
•
Photomicrograph of proliferative
mammary gland
proximal convoluted tubule
tortuous tubule close in proximity to the
glomerulus; the cuboidal cells of this
structure exhibit a prominent brush border; most of sodium-potassium and water
reabsorption occur here
•
Photomicrograph of proximal convoluted tubule
•
Photomicrograph of proximal convoluted tubule
proliferative phase of the endometrium
see endometrium
promonocyte
precursor of the monocyte; large cell with
a slightly indented nucleus and basophilic
cytoplasm
proximal straight tubule
tubule of the medullary ray; lined by cuboidal cells with weak brush borders
•
Photomicrograph of PST
promyelocyte
also known as "progranulocyte"; large cell
which is the earliest precursor of the granulocytes; has slightly indented nucleus
and distinct nucleolus; 16 um in diameter;
characterized by cytoplasmic azurophilic
granules; during maturation there is an in-
pseudostratified columnar epithelium
unilayer of columnar cells, all of whose
apices do not contact the lumen; the lining
of the trachea, bronchi, ductus deferens,
38
and ductus epididymis; suited for secretion, absorption, or duct-lining
•
Photomicrograph of pseudostratified columnar epithelium
•
Photomicrograph of pseudostratified ciliated columnar cell
R
pulmonary artery
vessel that brings deoxygenated blood to
the lungs
•
Photomicrograph of pulmonary artery
red blood cell
an erythrocyte; biconcave-shaped, enucleated cell responsible for oxygen delivery
and carbon dioxide removal
•
Photomicrograph of erythrocyte
pulmonary vein
vessel that brings oxygen rich blood from
the lungs to the heart; lined with cardiac
muscle
•
Photomicrograph of pulmonary
vein
red margin
area of the oral surface of the lip which is
thin and rich in blood vessels
red pulp
part of the spleen rich in red blood cells;
these are filtered and removed here (if
damaged)
•
Photomicrograph of red pulp
•
Photomicrograph of red pulp
Purkinje fiber
large, eosinophilic cells with prominent
nuclei specialized for conduction of electrical signals in the heart; allows for
rhythmicity of heartbeat
•
Photomicrograph of Purkinje fiber
Reissner's membrane
see vestibular membrane
pyknotic nucleus
a condensed nucleus; forms as a prelude to
apoptosis
releasing factor
hormone of the hypothalamus which stimulates secretion by the adenohypophysis
pyloric gland
gland of the stomach pylorus (region
which meets the duodenum); branched,
tubular glands containing mostly mucous
surface cells and some parietal and APUD
cells
renal calyx
see minor calyx
pyramid
cone-shaped structure which houses the
tubular networks of the numerous nephrons of the kidney parencyma
renal corpuscle
the combination of Bowman's capsule and
the glomerulus
renal column
cortical tissue in between two adjacent pyramids
renal lobule
a segment of a renal lobe; the lobe consists
of a pyramid and its surrounding connective tissue
residual body
39
1)see
lysosome
2)excess cytoplasm shed by the late spermatid
work for various tissues
•
Photomicrograph of reticular fiber
reticulocyte
same as polychromatophilic erythrocyte
resorption canal
a "tunnel" carved by osteoclasts advancing
through bony matrix during bone remodeling
retina
structure within the eye responsible for
photoreception; consists of several layers
(outer to inner):
•
pigmented epithelium
•
layer of rods and cones
•
outer limiting membrane
•
outer nuclear layer
•
outer plexiform layer
•
inner nuclear layer
•
inner plexiform layer
•
ganglion cell layer
•
optic nerve fiber layer
•
inner limiting membrane
respiratory bronchiole
see bronchiole
respiratory epithelium
epithelium of the respiratory portion of the
bronchial tree
respiratory portion
the structures of the respiratory system
that function in gas exchange; these include:
•
respiratory bronchioles
•
alveolar duct
•
alveolar sac
•
alveoli
ribosome
cellular structure responsible for translating mRNA message into protein product
resting mammary gland
same as inactive mammary gland
rod
photoreceptor of the retina responsible for
black/white vision
rete testis
channel lined with simple cuboidal epithelium that extends from the tubuli recti
•
Photomicrograph of rete testis
Rokitansky-Aschoff sinus
invagination of the gallbladder mucosa
that allows for bacterial aggregation, and
hence infection
reticular cell
1)this stellate cell has long processes
usually attached to the reticular fibers; the
processes cover "reticular fibers" which
are the collagenous stroma of the lymph
node
2)"adventitial cell"; may function as antigen-presenting
cell
3)cell of the bone marrow which provides
support for developing blood cells
•
Photomicrograph of reticular cell
rough endoplasmic reticulum (rER)
long, winding organelle which is studded
with ribosomes involved in producing proteins bound for secretion or plasma membrane integration
ruffled border
extensions of the membrane of the osteoclast involved in resorption of bony matrix
rugae
longitudinal folds of the inner stomach
reticular fiber
connective tissue element composed of
collagen III; provides supporting frame40
•
Photomicrograph of scala vestibuli
Schmidt-Lantermann cleft
space within the myelin sheath containing
Schwann cell cytoplasm
•
Photomicrograph of S-L cleft
S
Schwann cell
supporting cell of the peripheral nervous
system; forms the myelin sheath
•
Photomicrograph of Schwann cell
sarcolemma
plasma membrane of myofibers
sclera
opaque layer of dense connective tissue
covering the eye around the cornea
sarcomere
banded arrangement of myofilaments
which is the basic contractile unit in
striated muscle
sebaceous gland
gland of the epidermis that secretes an oily
coat which provides barrier and bacteriostatic function
•
Photomicrograph of sebaceous
gland
sarcoplasm
cytoplasm of muscle cells
sarcoplasmic reticulum
smooth endoplasmic reticulum (sER) of
skeletal, cardiac, and visceral striated
muscle (i.e. pharynx, tongue, and diaphragm) especially suited for sequestration/release of calcium
sebaceous gland of Zeis
oil gland associated with eyelashes
secondary center of ossification
center of bone deposition after birth; located in the upper epiphysis
satellite cell
1)cell that gives rise to new muscle cells
upon
injury
to
muscle
tissue
2)supporting cell of nerve cell bodies located in ganglia
•
Photomicrograph of satellite cell
secondary follicle
see folliculogenesis
secretory phase of the endometrium
see endometrium
scala media
middle compartment of the cochlear canal;
houses the basilar membrane and organ of
Corti
•
Photomicrograph of scala media
secretory vesicle
bud from the trans Golgi containing proteins bound for secretion
seminal colliculus
pyramid-shaped region between the prostatic sinuses
scala tympani
lowest compartment of the cochlear canal
•
Photomicrograph of scala tympani
seminiferous tubule
highly tortuous structure within which
male germ cells begin development
scala vestibuli
uppermost compartment of the cochlear
canal
41
septa
connective tissue within the parenchyma
of an organ (i.e. thymus, in which septa
emerge from the capsule into the parenchyma)
simple squamous epithelium
a single layer of squamous cells; found in
lining of body cavities, blood vessels, respiratory surfaces, and kidney elements;
ideal for both barrier and gas exchange
function
serosa
a mesothelium and its underlying connective tissue
sinusoid
see sinusoidal capillaries
serous acinus
circular arrangement of serous-secreting
cells
sinusoidal capillary
capillary whose basement membrane is
not fully adjoined and whose endothelial
cells maintain an intercellular distance;
found in liver, spleen, and bone marrow
•
Photomicrograph of sinusoid
•
Photomicrograph of sinusoidal capillary
serous cell
cell that secretes a watery fluid
serous demilune
a half moon-shaped structure attached to a
mucus gland which produces serous secretions
sinusoidal lining cell
endothelial cells which line sinusoids of
the bone marrow
serous gland
a gland whose secretions are watery rather
than organic
skeletal muscle
voluntary, striated muscle which allows
for body movement via rapid contractions;
the striations result from the banded pattern of the sarcomere
•
Photomicrograph of skeletal muscle
serous-secreting cell
see serous cell
Sertoli cell
columnar cells within the seminiferous
tubule; nourishes the developing germ cell
and protects them from antibodies by
forming the blood-testis barrier; also phagocytoses residual bodies
•
Photomicrograph of Sertoli cell
slit membrane
thin membrane covering the slit pores; influences filtration
slit pore
space between the foot processes of podocytes
simple columnar epithelium
a single layer of columnar cells typically
lining the digestive system; ideal for absorption
small granule cell
APUD cell of the respiratory epithelium
simple cuboidal epithelium
a single layer of cuboidal cells typically
lining ducts (i.e. exocrine ducts, kidney
tubules, etc.)
•
Photomicrograph of simple cuboidal epithelium
smooth endoplasmic reticulum (sER)
tubular organelle involved in:
•
lipid metabolism
•
glycogen metabolism
•
membrane formation
42
the process of spermatocyte formation;
occurs in the seminiferous tubule
smooth muscle
involuntary, non-striated muscle; allows
for slow, prolonged contraction
•
Photomicrograph of smooth muscle
•
Photomicrograph of smooth muscle
spermatogenesis
the process of spermatozoan development
from spermatogonia; occurs in the seminiferous tubule
smooth muscle cell
cell which resides in and secretes the matrix of smooth muscle; communicates with
other smooth muscle cells via gap junctions
•
Photomicrograph of smooth muscle
cell
spermatogonium
diploid stem cell of the male germ line
•
Photomicrograph of spermatogonia
spermatozoan
male germ cells; equipped with flagella
which allows it to travel to oocyte for fertilization
somatotrope
acidophilic cell of the adenohypophysis
which produces growth hormone (GH)
spermiogenesis
the development of spermatids into fully
mature spermatozoa; begins in the seminiferous tubule and continues through the
epididymis
space of Disse
space between the basal surfaces of the
hepatocytes and the basal surfaces of endothelial cells and Kupffer cells; region of
hepatocyte-blood exchange; also houses
the lipocytes
•
Photomicrograph of space of Disse
sphincter pupillae muscle
muscle of the iris which constricts the pupil
specific granule
container for antibacterial agents, such as
lysozyme; present in the granulocytes
spiral artery
vessel of the uterine lining which undergoes structural changes during the menstrual cycle; see endometrium
sperm
same as spermatozoa
spiral ganglion
group of nerve cell bodies located in the
modiolus; responsible for auditory reception
•
Photomicrograph of spiral ganglion
spermatid
see early and late spermatid
spermatocyte
•
primary spermatocyte- cell that is
the immediate mitotic descendant of the
spermatagonium; contains 4n DNA content due to S phase DNA synthesis
•
secondary spermatocyte- cell produced from the first meiotic division of
the primary spermatocyte
•
Photomicrograph of spermatocyte
spiral ligament
structure located along the lateral cochlear
wall; it is a thickening of the periosteum in
that region
•
Photomicrograph of spiral ligament
splenic cord
component of the spleen which consists of
reticular cells, macrophages, lymphocytes,
and granulocytes; located in the red pulp
spermatocytogenesis
43
•
•
Photomicrograph of splenic cord
Photomicrograph of splenic cord
exocrine glands; serves well as barrier and
conduit (duct-lining)
•
Photomicrograph of st. cub. epithelium
splenic nodule
areas of the splenic white pulp housing Blymphocytes
stratified squamous epithelium
multilayer of squamous cells; lining of
oral cavity, esophagus, epidermis, and vagina; serves as a barrier and protective
layer
splenic sinus
areas between splenic cords; located in the
red pulp
spongy bone
also known as "cancellous bone"; bone
consisting of many trabecular formations;
houses much blood supply
stratified squamous keratinized epithelium
see epidermis
stratified squamous non-keratinized epithelium
the lining of the vagina and the oral surface of the lip
spongy urethra
the part of the urethra within the penis
squamocolumnar junction
area which is a transition between the stratified squamous epithelium of the exocervix and the simple columnar epithelium of
the endocervix; the area where the former
epithelium overtakes the latter is known as
the transformation zone
•
Photomicrograph of squamocolumnar junction
stratum basalis
1)
see
2) see endometrium
epidermis
stratum corneum
see epidermis
stratum functionalis
see endometrium
squamous cell
a cell whose width dimension is greater
than its height
stratum granulosum
see epidermis
stem cell
any cell that serves as a precursor for
another, i.e. the basal cell of epithelia
stratum lucidum
see epidermis
stratum spinosum
see epidermis
stereocilium
unusually long microvilli present only in
the epididymis and hair cells of the ear
stria vascularis
located on lateral cochlear wall; site of
endolymph synthesis
•
Photomicrograph of stria vascularis
stratified columnar epithelium
a multilayer of columnar epithelial cells;
serves well as a barrier or in duct-lining
striated border
the brush border of the intestines
•
Photomicrograph of striated border
stratified cuboidal epithelium
multilayer of cuboidal cells that lines
sweat glands and ducts and some ducts of
44
striated duct
same as intralobular duct
phospholipid released by type II pneumocytes which prevents collapse of the alveolus
stroma
the supporting tissue of an organ; consists
of various connective tissue elements; see
also parenchyma
suspensory ligament
fiber connecting the lens to the ciliary
body; allow for ciliary muscle control of
the lens
subcapsular sinus
see cortical sinus
sustentacular cell
columnar cell that provides nutritional
support to olfactory cells
subendothelial layer of connective tissue
1) layer beneath the endocardium; houses
the conduction system of the heart
2) inner layer of the tunica intima
synapse
space between an axon and its target (neurons or effector cells)
sublingual gland
gland located in the floor of the mouth;
most are mucous glands some of which
house serous demilunes
•
Photomicrograph of sublingual
gland
syncytiotrophoblast
part of the trophoblast of the blastocyst;
multinucleate layer that embeds into the
endometrium
•
Photomicrograph of syncytiotrophoblast
submandibular gland
gland located on either side of the floor of
the mouth; are mostly serous glands and
some mucous glands
•
Photomicrograph of submandibular
gland
T
submucosa
a stabilizing layer of dense irregular connective tissue below the mucosa; provides
resistance to shearing forces
subpericardial adipose tissue
grouping of adipocytes beneath the pericardium
T tubule
internal extension of the plasma membrane in skeletal and cardiac muscle cells
which allow for rapid calcium entry (necessary for contraction)
supporting cell
same as sustentacular cell
tarsal gland
also known as Meibomian glands; long
sebaceous glands of the tarsal plates
suppressor T-lymphocyte
a cell which suppresses B-lymphocytes
activity to prevent a hyperimmune response
tarsal plate
flexible support of the eyelid; consists of
dense fibrous and elastic tissue
surfactant
45
territorial matrix
proteoglycan-rich matrix directly adjacent
to the lacuna of a chondrocyte (or isogenous group)
taste bud
specialized group of cells within the papillae of the dorsal tongue; allow for various
forms of taste
•
Photomicrograph of taste bud
testosterone
see Leydig cells
tectorial membrane
structure overlying the organ of Corti
which is involved in producing a shearing
effect on the hair cells upon vibration; this
process stimulates the hair cells, leading to
sound perception
theca externa
outer layer of connective tissue surrounding the growing follicle; contains many
smooth muscle cells
•
Photomicrograph of theca externa
•
Photomicrograph of theca externa
cell
tendinocyte
elongated cell with invisible cytoplasm
and flattened, poorly-stained, nucleus; appears in the tendon and is positioned in a
very regular pattern of rows between parallel bundles of collagen fibers; makes
fibers and ground substance of the tendon
•
Photomicrograph of tendinocyte
theca interna
inner layer of the connective tissue sheath
surrounding the maturing follicle; highly
vascularized; secrete androgens that are
converted by granulosa cells to estrogen
•
Photomicrograph of theca interna
•
Photomicrograph of theca interna
cell
tendon
dense regular connective tissue which
joins muscle to bone
•
Photomicrograph of tendon
theca lutein cell
cell of the corpus luteum derived from the
theca interna
•
Photomicrograph of theca lutein
cell
teniae coli
smooth muscle bands on the outer surface
of the colon (large intestine); three of
these strips can be seen macroscopically
•
Photomicrograph of teniae coli
thick filament
see myosin
terminal bar
light microscopy term for the junctional
complex
•
Photomicrograph of terminal bar
thin filament
see actin
thin segment
the thin, bottom portion of the loop of
Henle
•
Photomicrograph of thin segment
terminal bronchiole
see bronchiole
terminal web
a horizontal network of actin filaments
that crosses with the vertical microvillar
actin filaments to grant support, and perhaps contractile ability
thrombopoiesis
the process of clot formation
thymus cortex
see cortex
46
thymus medulla
see medulla
transitional epithelium
cellular layer capable of undergoing a
change in its property (i.e. shape of dome
cells of the bladder)
•
Photomicrograph of transitional epithelium
thyroid gland
produces triiodothyronine and thyroxine
which are responsible for aspects of metabolism, growth, etc.
thyrotrope
acidophilic cell of the adenohypophysis;
produces thyrotropic hormone (TSH)
tropocollagen
another name for the collagen molecule
tropomyosin
double helix protein which covers myosinbinding sites on actin filaments
tissue
a group of cells with a common structure
and function(s)
troponin
protein which is connected to tropomyosin
and along with it, block the myosinbinding site on the actin filament
tissue absorptive cell
see absorptive cell
T-lymphocyte
see lymphocyte
tubuli recti
small channels leading away from the seminiferous tubules; lined only by Sertoli
cells
•
Photomicrograph of tubuli recti
trabeculum
1) connected spicules which form a
meshwork
in
spongy
bone
2) connective tissue that extends from the
capsule into the substance of the lymph
node or spleen; houses various vessels,
including the trabecular artery and vein
•
Photomicrograph of trabecular vein
tunica adventitia
connective tissue tissue layer on the outside of arteries and veins which houses
nerves, vessels, and much adipose
•
Photomicrograph of tunica adventitia
•
Photomicrograph of tunica adventitia
trabeculum of spleen
see trabeculae
trabecular artery
see trabeculae
tunica albuginea
1)thick outer connective tissue covering of
the
testis
2)a dense fibroelastic sheath surrounding
the erectile tissue of the penis
3)dense connective tissue layer located
beneath the germinal epithelium of the
ovary
trabecular vein
see trabeculae
trachea
air conducting tube which branches into
the left and right bronchi; the bronchi further divide into secondary and tertiary
bronchi, and bronchioles, in that order
tunica intima
innermost layer of vessels; consists of the
endothelium and a subendothelial layer of
connective tissue
transformation zone
see squamocolumnar junction
47
•
with the proximal convoluted tubule
•
Photomicrograph of urinary pole
Photomicrograph of tunica intima
tunica media
intermediate layer of vessels; has much
smooth muscle and connective tissue
•
Photomicrograph of tunica media
•
Photomicrograph of tunica media
urinary space
space between the visceral and parietal
layers of Bowman's capsule; site of filtrate
delivery
•
Photomicrograph of urinary space
type I pneumocyte
squamous cell that lines most of the alveolar surface
•
Photomicrograph of type I pneumocyte
uterine discharge
menstrual flow; composed of epithelial
cells and blood
uterine gland
glands of the uterine mucosa; see endometrium
type II pneumocyte
cuboidal cell that is part of the alveolar
lining; secretes surfactant
•
Photomicrograph of type II pneumocyte
uterine stroma
see stroma
uterus
female reproductive organ which houses
and supports the developing embryo
•
Photomicrograph of uterus
U
VWZ
umbilical artery
maternal vessel whose branches pass into
the villi and exchange material with the
fetal circulation
vagina
fibromuscular tube opening into the cervix; lined with stratified squamous epithelium
unmyelinated axon
those lacking a myelin sheath; are relatively slow in conduction
•
Photomicrograph of unmyelinated
nerve
valve
a structure within blood and lymph vessels
that prevents backflow
urethra
a channel originating in the bladder that
delivers semen and urine through the penis
vasa recta
the vessels that supply and exchange substances with the tubular network of a juxtamedullary nephron
urinary pole of the renal corpuscle
the pole of the renal corpuscle continuous
48
•
Photomicrograph of intestinal villus
2) see chorionic villus
vasa vasorum
blood supply located in the tunica adventitia
visceral pleura
see serosa
vascular pole of renal corpuscle
the entry/exit point of the afferent arteriole
and efferent arteriole, respectively, from
the renal corpuscle
vitreous cavity
space containing the vitreous humor of the
eye
•
Photomicrograph of vitreous body
vascular space
opening within erectile tissue lined by endothelial cells; allows for profuse blood
flow during erection
vitreous humor
gel-like substance that fills the posterior
portion of the eye; gives the eye its shape
vein
vessel which carries oxygen-poor blood
away from tissues to the heart
•
Photomicrograph of a large vein
vocal fold
two folds of musoca within the larynx; vibrations of these folds produce sound
pitch
venous sinus
venous channel of the cranial cavity lined
with endothelial cells
•
Photomicrograph of venous sinus
Volkmann's canal
channel which allows passage of blood
vessels and nerves from the periosteal
layer to the Haversian canals
•
Photomicrograph of Volkmann's
canal
ventricular fold
mucosal fold of the larynx located above
the vocal folds; important in resonance
von Ebner's gland
serous gland at the base of papillae that
wash away food particles
•
Photomicrograph of von Ebner's
gland
venule
small vessel carrying deoxygenated blood;
located between a capillary and a small
vein
•
Photomicrograph of venule
•
Photomicrograph of venule
wandering cell
a cell that can travels distances to execute
their function; i.e. lymphocytes, granulocytes, and monocytes
vessel
see blood vessel
vestibular membrane
also known as "Reissner's membrane"; the
upper wall of the scala media
•
Photomicrograph of vestibular
membrane
white blood cell
a cell of the immune system; known also
as leukocyte
white pulp
area of the spleen rich in lymphocytes
•
Photomicrograph of white pulp
•
Photomicrograph of white pulp
villus
1) finger-like extension of the mucosa of
the small intestine
49
Z line
see Z-disk
zone of hypertrophy
layer of massive chondrocytes containing
large stores of glycogen
•
Photomicrograph of zone of hypertrophy
Z-disk
anchoring area for actin filaments in the
sarcomere
•
Photomicrograph of Z-disk
zone of proliferation
layer of large chondrocytes undergoing
active growth and division
•
Photomicrograph of zone of proliferation
zona fasciculata
middle zone of the adrenal cortex composed of cord-like arrangement of cells;
site of glucocorticoid production; glucocorticoids function in:
•
conversion of amino acids to glucose
•
fatty acid breakdown
•
catabolism of fatty acids and amino
acids
•
suppression of inflammation
•
Photomicrograph of zona fasiculata
zone of reserve cartilage
layer of little cellular growth or matrix
production
•
Photomicrograph of zone of reserve
cartilage
zone of resorption
layer closest to shaft of bone; cartilage is
actively digested by osteoclasts here
•
Photomicrograph of zone of resorption
zona glomerulosa
outer zone of the adrenal cortex; cells here
secrete mineralocorticoids (i.e. aldosterone), which function in the resorption of
sodium at the expense of potassium
•
Photomicrograph of zona glomerulosa
zonula adherens
relatively weak band-like intercellular adhesion on lateral cell surface
zona pellucida
acidophilic layer between the oocyte and
adjacent follicular cells; first appears in
the primary follicle
•
Photomicrograph of zona pellucida
zonula occludens
lateral surface cellular adhesion which
serves as a diffusion barrier
zymogen granule
acidophilic granule containing secretory
products in their inactive forms, i.e. granules of the pancreatic acinar cells contain
trysinogen, chymotrypsinogen, etc.
zona reticularis
the innermost zone of the adrenal cortex;
produces weak androgens and some glucocorticoids
•
Photomicrograph of zona reticularis
zone of calcified cartilage
layer where chondrocytes degenerate due
to calcification of matrix; see calcified
cartilage
•
Photomicrograph of zone of calcified cartilage
50
51
52