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CHAPTER
4
Tissue: The Living Fabric
Objectives
Preparing Human Tissue for Microscopy
1. List the steps involved in preparing animal tissue for microscopic viewing.
Epithelial Tissue
2. List several structural and functional characteristics of epithelial tissue.
Connective Tissue
7. Indicate common characteristics of connective tissue, and list and describe its structural
elements.
Muscle Tissue
9. Compare and contrast the structures and body locations of the three types of muscle tissue.
Tissue Repair
12. Outline the process of tissue repair involved in normal healing of a superficial wound.
Developmental Aspects of Tissues
Suggested Lecture Outline
I. Preparing Human Tissue for Microscopy (pp. 117–118)
A. Tissue specimens must be fixed (preserved) and sectioned (sliced) thinly enough to allow
light transmission. (p. 117)
II. Epithelial Tissue (pp. 118–126; Figs. 4.1–4.6)
A. Features of Epithelia (p. 118)
1. Epithelium occurs in the body as covering or lining epithelium, or as glandular
epithelium.
B. Special Characteristics of Epithelium (pp. 118–119)
1. Exhibits polarity by having an upper free apical surface, and a lower attached basal
surface.
2. Epithelial tissues are continuous sheets that have little space between cells.
C. Classification of Epithelia (pp. 119–124; Figs. 4.2–4.3)
1. Each epithelial tissue has a two-part name: the first part indicates the number of layers
present, and the second part describes the shape of the cells.
2. A simple epithelium consists of a single layer of cells that functions in absorption,
secretion, and filtration.
a. Simple squamous epithelium is located where filtration or exchange of substances
occurs.
3. A stratified epithelium is made up of several layers of cells that mostly provide
protection.
a. Stratified squamous epithelium makes up the external part of the skin, and extends
c. Stratified columnar epithelium is found in the pharynx, in the male urethra, and
lining some glandular ducts.
D. Glandular Epithelia (pp. 124–126; Figs. 4.4–4.6)
1. Endocrine glands are ductless glands that secrete hormones by exocytosis directly into
the blood or lymph.
2. Exocrine glands have ducts and secrete their product onto a surface or into body
cavities.
a. Unicellular exocrine glands secrete mucus to epithelial linings of the intestinal or
respiratory tract.
III. Connective Tissue (pp. 127–136; Figs. 4.7–4.8; Table 4.1)
A. Functions of Connective Tissue (p. 127; Table 4.1)
1. The major functions of connective tissue are binding and support, protection, insula-
tion, storing fuel, and transporting substances in the body.
B. Common Characteristics of Connective Tissue (p. 127)
1. All connective tissue arises from an embryonic tissue called mesenchyme.
C. Structural Elements of Connective Tissue (pp. 127–129; Fig. 4.7)
1. Ground substance fills the space between the cells and consists of interstitial fluid, cell
adhesion proteins, proteoglycans, and protein fibers.
2. Fibers of the connective tissue provide support.
3. Each major class of connective tissue has a fundamental cell type that exists in
immature and mature forms.
D. Types of Connective Tissue (pp. 129–137; Fig. 4.8; Table 4.1)
1. Mesenchyme forms during the early weeks of embryonic development from the
mesoderm layer and eventually differentiates into all other connective tissues.
3. Dense connective tissue is one of the two subclasses of connective tissue proper.
a. Dense regular connective tissue contains closely packed bundles of collagen fibers
4. Cartilage lacks nerve fibers and is avascular.
a. Hyaline cartilage is the most abundant cartilage, providing firm support with some
5. Bone (osseous tissue) has an exceptional ability to support and protect body structures
due to its hardness, which is determined by the additional collagen fibers and calcium
salts found in the extracellular matrix.
IV. Muscle Tissue (pp. 136–139; Fig. 4.9)
A. Muscle tissues are highly cellular, well-vascularized tissues responsible for movement
(p. 136; Fig. 4.9).
B. There are three types of muscular tissue (p. 138; Fig. 4.9):
1. Skeletal muscle attaches to the skeleton and produces voluntary body movement.
V. Nervous Tissue (p. 140; Fig. 4.10)
A. Nervous tissue is the main component of the nervous system, which regulates and
controls body functions (p. 140; Fig. 4.10).
B. Nervous tissue is composed of two types of cells (p. 140; Fig. 4.10).
1. Neurons are specialized cells that generate and conduct electrical impulses.
VI. Covering and Lining Membranes (pp. 140–142; Fig. 4.11)
A. The cutaneous membrane, or skin, consists of a keratinized stratified squamous epithe-
lium attached to a thick layer of dense irregular connective tissue (p. 140; Fig. 4.11).
C. Serous membranes are mist membranes within closed body cavities, and consist of
simple squamous epithelium resting on a thin layer of loose connective (areolar) tissue
(p. 142; Fig. 4.11).
VII. Tissue Repair (pp. 142–144; Fig. 4.12)
A. Tissue repair occurs in two ways: regeneration, in which damaged cells are replaced with
the same type of cell; and fibrosis, which replaces damaged cells with fibrous connective
tissue (p. 142).
B. Three steps are involved in the tissue repair process (pp. 142–143; Fig. 4.12).
1. Cellular damage promotes inflammation, which prepares the area for the repair
process.
VIII. Developmental Aspects of Tissues (pp. 144, 146; Fig. 4.13)
A. Embryonic and Fetal Development of Tissues (p. 144; Fig. 4.13)
1. Primary germ layer formation is one of the first events of embryonic development,
giving rise to three layers of tissue, ectoderm, mesoderm, and endoderm.
Cross References
Additional information on topics covered in Chapter 4 can be found in the chapters listed below.
1. Chapter 1: The hierarchy of structural organization; divisions of the ventral body cavity
4. Chapter 8: Connective tissues in ligaments and tendons; cartilage in joint formation
5. Chapter 9: Skeletal and smooth muscle; connective tissue coverings of muscles
6. Chapter 11: Nervous tissue
7. Chapter 13: Function of nervous tissue
11. Chapter 19: Epithelial and connective tissue components of the blood vessels
12. Chapter 20: Interstitial fluid (generation and removal); reticular connective tissue support
of lymphoid tissue
Lecture Hints
1. The relationship between structure and function is important and can be readily illus-
2. Stratified squamous epithelium is usually the first of the multilayered epithelial tissues
presented. Emphasize that only the surface cells are flattened. The student’s first concep-
tion is often that the tissue is composed of multiple layers of thin flat cells.
3. Emphasize the uniqueness of the matrix when explaining the classification of the connec-
4. As a way to illustrate the relationship between structure and function introduced in
Chapter 3, compare the amount of extracellular matrix in connective tissue with that in
5. Students are sometimes confused about why collagen and elastic fibers are called white
6. Point out that hyaline cartilage contains large numbers of collagen fibers even though
they will not be visible on the slides observed in the lab.
7. Emphasize that cartilage is avascular and that this results in a slow repair or healing rate.
8. While presenting the information on bone (osseous tissue), stress that it is living tissue
that has a direct blood supply. Often, the student conception of bone is that it is nonliving
material (due to observations in the lab).
9. Mention that the “fibers” in blood are unique because they are composed of a soluble
protein that becomes insoluble only during the process of clot formation.
11. As a way of giving students perspective on the specialization of tissues, note that there
12. Stress that regeneration is not the same as repair.
Activities/Demonstrations
1. Audiovisual materials are listed in the Multimedia in the Classroom and Lab section of
this Instructor Guide (p. 387).
2. Ask the students to make a list of all the things the body could not do if connective tissue
were absent.
4. In the lab, cut a planaria transversely and follow the regeneration of the missing body
region over the next few weeks.
6. Obtain or prepare 2x2 slides of all the tissues used during the lecture presentation of
histology.
7. Illustrate how tissues are sectioned to show how thin sections are made. Remind students
that slides possess only a small, thin slice of tissue and that the slide may have more than
one type of tissue.
9. Cover your fist with a collapsed balloon to demonstrate the relationship between parietal
and visceral layers of a serous membrane.
10. Use a human torso model to indicate the locations of mucous and serous membranes.
Critical Thinking/Discussion Topics
1. How are tissues prepared and sectioned to produce the various tissue slides seen in this
textbook?
2. How are tissues used in the body to create specific body compartments, and why is this
necessary?
6. Since cartilage is avascular, how is it supplied with the essentials of life?
7. Other than to reduce bleeding and prevent microbial invasion, why are wounds sutured?
Library Research Topics
1. Basement membranes provide the interface between epithelium and connective tissue.
What is the chemical composition of this layer and why is this area of great interest to
cell biologists?
2. What is the current status of cloning? Is it feasible for human cells?
List of Figures and Tables
All of the figures in the main text are available in JPEG format, PPT, and labeled & unlabeled
format on the Instructor Resource DVD. All of the figures and tables will also be available in
Transparency Acetate format. For more information, go to www.pearsonhighered.com/educator.
Figure 4.1 Overview of four basic tissue types: epithelial, connective, muscle,
and nervous tissues.
Figure 4.7 Areolar connective tissue: A prototype (model) connective tissue.
Figure 4.8 Connective tissues.
Figure 4.9 Muscle tissues.
Figure 4.10 Nervous tissue.
Figure 4.11 Classes of membranes.
Answers to End-of-Chapter Questions
Multiple-Choice and Matching Question answers appear in Appendix H of the main text.
Short Answer Essay Questions
7. Tissues are groups of closely associated cells that are similar in structure and perform a
common function. (p. 117)
9. The covering and lining epithelia are classified on the basis of the shape of the cells and
the number of cell layers present. The three common shapes are squamous, cuboidal, and
10. Merocrine glands (sweat glands) secrete their products by exocytosis; holocrine glands
11. Binding—areolar; support—cartilage; protection—bone; insulation—adipose; and trans-
portation—blood. (p. 127)
12. The primary cell type in connective tissue proper is the fibroblast; in cartilage, the
chondroblast; and in bone, the osteoblast. (p. 128)
13. The two major components of matrix are: ground substance—interstitial fluid, proteogly-
cans, and glycosaminoglycans; and protein fibers—collagen, elastic, reticular. (p. 127)
15. a. areolar connective tissue (p. 130)
b. elastic cartilage (p. 134)
c. elastic connective tissue (p. 132)
16. The macrophage system is involved in overall body defenses. Its cells are phagocytotic
and act in the immune response. (p. 128)
17. Neurons are highly specialized cells that generate and conduct nerve impulses, whereas
the supporting cells (neuroglial) are nonconducting cells that support, insulate, and
protect the neurons. (p. 140)
19. Tissue repair begins during the inflammatory response with organization, during which
the blood clot is replaced by granulation tissue. If the wound is small and the damaged
20. Ectoderm—epithelium and nervous; mesoderm—connective, muscle, and epithelium;
endoderm—epithelium. (p. 144)
21. Adipose and bone tissue are similar in that both tissues are connective tissues with a rich
Critical Thinking and Clinical Application Questions
1. No, his recovery will likely be slow. Cartilage heals slowly because it lacks the blood
supply necessary for a quick, efficient healing process. (p. 132)
2. The skin is subjected to almost constant friction, which wears away the surface cells, and
is charged with preventing the entry of damaging agents and with preventing water loss
3. If ligaments contained more elastic fibers they would be more stretchy; thus joints would
be more flexible. However, the function of the ligaments is to bond bones together
4. Adenomas and carcinomas are derived from epithelium, because epithelial tissues remain
mitotic throughout life. This is not the case for nervous and muscle tissue, and some
forms of connective tissue. Also keep in mind that the prefix adeno- indicates a glandular
origin, which is epithelial tissue. (p. 119)
5. Whereas “white” fat stores nutrients, “brown” fat uses its nutrient stores to produce heat,
6. Beef tenderloin is skeletal muscle. Cow tripe is digestive smooth muscle. (p. 138)
Suggested Readings
Becerra, J., et al. “The Stem Cell Niche Should Be a Key Issue for Cell Therapy in Regenera-
tive Medicine.” Stem Cell Reviews and Reports 7 (2) (June 2011): 248–255.
Cormack, D. H. Essential Histology. 2nd ed. New York: J. B. Lippincott Company, 2000.
McCormick, Frank. “New-Age Drug Meets Resistance.” Nature 412 (6844) (July 2001):
281–282.
Papatriantafyllou, Maria. “Macrophages: Iron Macrophages.” Nature Reviews Immunology
11 (3) (Mar. 2011): 158–159.
