Download Connective Tissue - Model High School

Cells combine to form tissues, and tissues
combine to form organs
Tissues are groups of cells closely associated
that have a similar structure
& perform a related function
Cells combine to form 4
primary tissues
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 Epithelial Tissue Locations:
◦ Covers the body
◦ Lines the cavities, tubes, ducts and blood vessels
inside the body
Covers the organs inside body cavities
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 Epithelial Tissue Functions:
◦ Protection from physical & chemical injury,
◦ Protection against microbial invasion,
◦ Contains receptors which respond to stimuli,
◦ Filters, secretes & reabsorbs materials and
◦ Secretes serous fluids to lubricate structures.
 Two types:
o membranous epithelia form the coverings or
linings of organs
o glandular epithelia form exocrine and
endocrine glands
 Sheets of cells with specialized contacts & cell
junctions
o Basal lamina: protein scaffolding secreted by
epithelial cells
o Basement membrane: reticular fibers (crossed
collagen network) that supports epithelium--really
associated connective tissue
 Connective tissue support
 Nutrients from capillaries in underlying connective
tissue
 Nerves pass through
 Easily regenerates
 Different cell shapes & arrangements
Simple: just one
layer or cell shape
Stratified: multiple
layers and cell shapes
TYPE
Squamous
CELL SHAPE
Squashed
Cuboidal
Cubed
Columnar
Columns
Pseudo-stratified
Flat cells
give rise to
columns
EXAMPLE
Endothelium (lines blood
vessels), mesothelium
(serous lining of celom)
Walls of glands
Lining of gut tube;
sometimes with cilia like
lining of uterine tube
With cilia in respiratory
tubes to move mucous &
particles out of the lungs
 Simple Squamous
o One cell thick
o Forms solid layer of cells
which line blood vessels,
body cavities & cover
organs in body cavities
o Lubrication
 Stratified Squamous
o Multiple layers
o Forms epidermis (Skin)
lining of the mouth
o Lubrication & protection
 Simple Cuboidal
o One cell thick, roughly cube
shaped
o Lines ovaries, kidneys, thyroid
glands, where secretion &
absorption take place
 Stratified Cuboidal
o In multiple layers w/one layer
attached to basement membrane
& one w/free edge
o Mammary & sweat glands
o Secretion, absorption &
protection
 Simple Columnar
o One cell thick column
shaped (long & narrow)
o Line digestive tract where
re-absorption & secretion
occurs.
 Stratified Columnar
o Stacked nucleus on top of
nucleus
o Lines vas deferans, male
urethra
o Gives support and some
movement.
 Pseudostratified
o gives the appearance of
more than one layer of
columnar epithelial cells
o Every cell is attached to
the basement membrane
o Lines the trachea,
fallopian tubes
o movement
 Transitional
o Several layers of epithelial cells
o Forms tissue that must stretch like the
bladder
o Stretches, protects against seepage
Glandular Epithelia
 Glandular
o A gland consists of one or more cells that
make and secrete a particular product.
o Endocrine: secretions diffuse directly into
the blood vessels. Ex.– thyroid, adrenals,
pituitary
o
Exocrine: secretions empty through the
ducts to the epithelial surface. Ex.- sweat,
oil
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 Muscle Tissue:
o Associated with the bones of the
skeleton, the heart and in the walls of
the hollow organs of the body.
 Muscle Tissue Functions:
o Movement & Locomotion
o Maintains posture
o Produces heat
o Facial expressions
o Pumps blood
o Peristalsis
 Consists of specialized cells that contract when
stimulated
 The body has three types of muscle tissue:
o
o
o
Skeletal
Cardiac
Smooth muscle
 Cardiac (involuntary) HEART
 Smooth (involuntary) ORGANS
 Skeletal (voluntary) BONES
Cardiac Muscle
Smooth Muscle
Skeletal Muscle
 Connective tissue location:
o Most abundant & widely distributed tissue
o Connective tissue has non-living extracellular material (matrix between its cells
 Connective Tissue Functions:
o Connects, binds and supports structures,
o Tendons, ligaments, etc.
o Protects & cushions organs and tissues,
o Insulates (fat) and
o Transports substances (blood).
 Major classes:
o Bone
o Cartilage
o Loose
o Dense
o Blood
 All connective tissues
consist of two basic
components:
o Living cells
o Extracellular matrix
 Fibers
o
Collagen gives structure
Reticular fibers (crossed
collagen) gives order
o Elastin gives elasticity
 Ground substance
o Jelly-like material made of
sugar-protein molecules
(proteoglycans)
o Allows connective tissue to
retain water and serve as
support and protection of
organs
o
Type: Loose, adipose
Type: Loose, areolar
 Contains elastin
 Nourishes & stretches
o Provides blood vessels to skin
o Fills muscle gaps
Adipose
o Stores energy (fat) & insulates
o Mostly under the skin
Areolar
o Wraps the organs
o Cushions & protects
 Dense Fibrous
o Collagen is the main
matrix element
o Thick fibers running in
many planes
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o
Dermis, fibrous capsules
around organs
Aligned parallel fibers that
resists tension
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Tendon, ligaments
 Perform specific functions essential to
homeostasis
 The body contains three types of
specialized connective tissue:
o
o
o
Bone
Cartilage
Blood
 Bone
o
o
Consists of bone cells
(osteocytes) and a calcified
cartilage matrix
Two types of bone tissue
exist: spongy and compact
 Tree ring-like appearance
 Supports & protects
 Mineral storage
 Fat storage
 Blood cell production
 Supports while providing
flexibility
 Hyaline cartilage absorbs
compression between bones
in joints (bone ends)
o Most abundant type of
cartilage found in the body
 Fibrocartilage forms cushion
like disks between the
vertebra
 The ears and nose are more
flexible and are elastic
cartilage
 Blood
o Red & white blood cells
o Platelets
o Plasma
o Regulates temperature
o Transportation system
 Nervous Tissue:
◦ Main component of the nervous system
ie., brain, spinal cord & nerves.
 Nervous Tissue Functions:
◦ Regulates & controls body functions
◦ Generates & transmits nerve impulses
◦ Supports, insulates and protects
impulse generating neurons.
 Contains specialized
cells that conduct
impulses
 Conducting cells,
called neurons,
transmit impulses from
one region of the body
to another.
 Nonconducting cells,
neuroglia, are a type of
nervous system
connective tissue.