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Tissue Picture Book
The study of tissues, called histology, is microscopic anatomy. Individual tissues consist
of cells and extracellular material that have a particular function. Organs of the body are
formed by two or more tissues. The study of histology is very important because many
organic dysfunctions of the human body are diagnosed at the tissue level. Surgical
specimens are routinely sent to pathology labs so that accurate assessment of the health of
the tissue, and ultimately the patient, can be made.
The human body is a complex machine made up of many parts. Although diverse in
structure and function, all body parts are constructed of four basic tissue types: 1)
epithelia, 2) connective, 3) muscle, and 4) nervous tissues. Consider these basic tissue
types as the "building blocks" of the human body. During development, these building
blocks are put together in many different ways to build the anatomical elements of the
body.
Anatomy always relates to physiology or more concisely, structure relates to function.
Remember this as you learn about these tissue types. The differences between tissues
and how they might appear under the microscope always relates to the particular
functions they provide.
Let us begin our understanding of tissues by introducing ourselves to the four basic tissue
types and the broad functions they provide:
Tissue Type
Epithelia
Broad Function
Act as protective linings and coverings. In some locales, absorption and
secretion are important functions of these lining and covering cells. As
secretory cells, epithelia form most glandular structures of the body.
Serve as connective and supportive tissues that bind and hold body
Connective structures together. Specialized fluid connective tissue types serve as
liquid media important in transport, exchange, and body defense.
Muscle
Tissues with the unique capability to contract or shorten. This enables
muscle types to be involved in functions of support and movement.
Nervous
Nerve cells are specialized for conduction. Nervous tissues therefore
serve as the complex telecommunications network of the body. These
tissues act in a sensory capacity, to receive, disseminate, and store
information collected from receptors. In a motor capacity, nervous tissues
provide response potential by controlling effectors such as muscles or
glands.
Simple Epithelia
Simple epithelia serve many roles in various body locales. As components of serous and
synovial membranes, simple epithelia secrete fluids that lubricate tissues to minimize
friction as organs or other body structures rub against one another. Other simple epithelia
line body tracts as protective, absorptive, or secretory cells. All glands of the body are
constructed of epithelial cells as are the ducts that connect the exocrine types to body
surfaces. As linings in the alveoli(air sacs), kidneys, and blood vessels, simple squamous
types assist in diffusion, osmosis and filtration phenomena. As linings and covering on
all external and internal body surfaces, epithelia serve as the "first line of defense" against
microbial invasions.
Draw what you see in the microscope in the space provided. Be sure to label any nuclei
and other important structures you may see. You should have at least 3 different parts
labeled for each field view. Refer to the info cards at each station, the posters around the
room and your textbook for ideas.
Where in the body do you find
simple squamous epithelium?
_________________
What is its function?
__________________
Simple squamous epithelium - lung
Where in the body do you find
simple cuboidal epithelium?
_________________
What is its function?
__________________
Simple cuboidal epithelium - kidney tubules
Where in the body would you find simple
columnar epithelium?
________________________
What are the light pink/whitish areas within
the epithelium and what are they secreting?
__________________________
Why is this an important secretion in this
part of the body?
_________________________________
Simple columnar epithelium - small intestine
Where in the body do you find
Pseudostratified ciliated columnar
epithelium?
_________________
What is its function?
__________________
What function do the cilia serve?
____________________________
Pseudostratified ciliated columnar epithelium trachea
Stratified Epithelium
Where in the body do you find
Stratified Squamous epithelium?
_________________
What is its function?
__________________
Stratified Squamous
Where in the body do you find
Stratified Cuboidal epithelium?
_________________
What is its function?
__________________
Stratified cuboidal epithelium
Where in the body would you find Stratified
Columnar epithelium?
________________________
Where in the body is this found?
_________________________________
Stratified Columnar Epithelium
Where in the body do you find
Transitional epithelium?
_________________
What is its function?
__________________
Transitional Epithelium
Connective Tissue
In contrast to epithelial tissues where cells are tightly adherent to one another, connective
tissues consist of dispersed cells that typically lack intercellular contact. Also, most
connective tissues are vascularized with the single exception being cartilage.
Extracellular spaces in connective tissues are therefore more abundant and contain
vessels. In connective tissues, the extracellular space is termed the extracellular matrix
because products of specialized cells accumulate here. These products include protein
fibers and ground substances (mixes of various chemical substances).
Connective tissues are broadly classified into three large groups:
Connective Tissue Category
Tissue Types
1. Fluid Connective Tissues
Blood and Lymph
2. Connective Tissue Proper
Loose and Dense Connective Tissues
3. Supportive Connective Tissues Cartilage and Bone
Fluid connective tissue types, of which there are only two, are important in transport and
body defense. Most connective tissues are variants of the second group, connective
tissue proper where cells are interspersed among protein fibers in a fluid-filled matrix.
Supportive connective tissues include cartilage and bone, more durable connective tissue
types due to the semisolid or solid ground substance that accumulates in the matrix. Since
the matrix of supportive connective tissues is either a semisolid or solid, cells of these
tissues occupy small spaces or lacunae.
Draw what you see in the microscope in the space provided. Be sure to label any nuclei
and other important structures you may see. You should have at least 3 different parts
labeled for each field view. Refer to the info cards at each station, the posters around the
room and your textbook for ideas.
There are many light pink cells in the
microscope field. What type of
blood cell are they?
____________________________
There are also a few larger blood
cells in the microscope field. What
type of blood cell are they?
____________________________
Blood
Where in the body do you find loose
connective tissue?
_________________
What is its function?
__________________
Loose connective tissue - Adipose
Where in the body do you find
Dense connective tissue?
_________________
What is its function?
__________________
Dense connective tissue - tendon
Where in the body do you find Irregular connective
tissue?
_________________
What is its function?
__________________
Dense Irregular Connective Tissue
Where in the body do you find Areolar connective
tissue?
_________________
What is its function?
________________
Areolar Connective Tissue
Where in the body do you find
Hyaline Cartilage?
_________________
What is its function?
__________________
Supportive Connective Tissue – Hyaline Cartilage
Where in the body do you find Elastic
Cartilage?
_________________
What is its function?
__________________
Supportive Connective Tissue – Elastic Cartilage
Where in the body do you find Fibrocartilage?
_________________
What is its function?
__________________
Supportive Connective Tissue – Fibrocartilage
Where in the body do you find
Bone?
_________________
What are its 5 functions?
1
2
3
4
5
Supportive Connective Tissue - Bone
Muscle Tissue
All muscle tissues are specialized for contraction, possessing the ability to shorten and
therefore create a contractile force. Substantial metabolism is necessary to produce
energy for these contractions and a useful by-product of chemical reactions is heat.
Therefore, muscles contribute to thermoregulation, the maintenance of body
temperature. Functions of muscles in our bodies include:




support and movement
propulsion of blood through vessels
movement of food or body secretions through tracts
thermoregulation
Muscle cells possess other attributes besides contractility. All muscles are excitable, able
to respond to stimuli, an important capability also common to nervous tissues. Muscles
are extensible in that they can be stretched and still maintain contractile ability. As we
will see, some muscles are better at this than others. Finally, muscle cells are associated
with elastic connective tissues. These connective tissue elements enable muscles to
contract or stretch and then return to their original length, an attribute called elasticity.
Muscle types vary in their appearance histologically but one common attribute applies to
all varieties, the cells of muscles are long and narrow. For this reason, the term fiber is
common descriptive term for muscle cells. Muscle cells, therefore are also muscle fibers
or more specifically myofibers. There are three types of myofibers:
1. skeletal
2. cardiac
3. smooth
Skeletal and cardiac muscles are classified as striated types while smooth is a non-striated
type. The term "striated" describes the repeating dark and light bands visible in
longitudinal views of cardiac and skeletal muscle types. These bands are important in the
identification of skeletal and cardiac muscle in longitudinal sections. You will learn later
these striations are the result of highly organized arrangements of contractile proteins
within muscles. Smooth muscle also has contractile proteins but these are arranged
randomly.
Draw what you see in the microscope in the space provided. Be sure to label any nuclei
and other important structures you may see. You should have at least 3 different parts
labeled for each field view. Refer to the info cards at each station, the posters around the
room and your textbook for ideas.
Where in the body do you find
Skeletal Muscle?
_________________
What is its function?
__________________
Is it voluntary or involuntary?
________________________
Muscle tissue - Skeletal Muscle
Where in the body do you find
Cardiac Muscle?
_________________
What is its function?
__________________
Is it voluntary or involuntary?
________________________
Muscle Tissue - Cardiac Muscle
Where in the body do you find
Smooth Muscle?
_________________
What is its function?
__________________
Is it voluntary or involuntary?
________________________
Muscle Tissue - Smooth Muscle
Nervous Tissue
Nervous tissue includes all cells that provide communication between other tissue types.
Think of nervous tissue as the communication network of the body, consisting of a
master computer(the brain) linked to multiple sites via complex cabling and wires(the
spinal cord and nerves). Various sensing devices(receptors) provide input to the
computer and when necessary the computer controls machine response(effectors such as
muscles or glands).
Draw what you see in the microscope in the space provided. Be sure to label any nuclei
and other important structures you may see. You should have at least 3 different parts
labeled for each field view. Refer to the info cards at each station, the posters around the
room and your textbook for ideas.
Where in the body do you find
Neurons?
_________________
What function do they serve?
__________________
What are the support cells called?
_________________________
What do they do?
_________________________
Nervous Tissue - Neurons