Lesson 3 Tissues

Question 1

What is tissue repair?

Answer 1

Substitution of viable cells for dead cells by regeneration or replacement.

Question 2

Define regeneration in the context of tissue repair.

Answer 2

New cells of same type are produced; function is restored.

Question 3

What does replacement mean in tissue repair?

Answer 3

New type of tissue develops, resulting in scar and loss of function.

Question 4

What are the three classifications of cells based on their ability to regenerate?

Answer 4

• Labile
• Stable
• Permanent

Question 5

What type of cells are classified as labile?

Answer 5

Capable of mitosis through life; examples include skin, mucous membranes, hemopoietic tissue, lymphatic tissue.

Question 6

Describe stable cells.

Answer 6

No mitosis after growth ends, but can divide after injury; examples include liver, pancreas, endocrine cells.

Question 7

What are permanent cells?

Answer 7

If killed, replaced by a different type of cell; limited regenerative ability; examples include nervous, skeletal, and cardiac muscle.

Question 8

What are the two types of embryonic connective tissue?

Answer 8

• Mesenchyme
• Mucous CT

Question 9

What is mesenchyme?

Answer 9

Source of all adult connective tissue; forms primarily from mesoderm.

Question 10

What is the composition of areolar connective tissue?

Answer 10

Loose packing material containing collagen, reticular, elastic fibers and five types of cells.

Question 11

What are the predominant cells in adipose tissue?

Answer 11

Adipocytes.

Question 12

What distinguishes brown adipose tissue from yellow adipose tissue?

Answer 12

Brown is found only in specific areas; yellow is more abundant and has a wide distribution.

Question 13

What is the function of reticular tissue?

Answer 13

Forms superstructure of lymphatic and hemopoietic tissues.

Question 14

What are the three major components of the extracellular matrix?

Answer 14

• Protein fibers
• Ground substance
• Fluid

Question 15

Identify the three types of protein fibers in connective tissue.

Answer 15

• Collagen
• Reticular
• Elastic

Question 16

What are the functions of connective tissue?

Answer 16

• Enclose organs
• Connect tissues
• Support and movement
• Storage
• Cushion and insulate
• Transport
• Protect

Question 17

What are the roles of fibroblasts, fibrocytes, and osteoclasts?

Answer 17

• Fibroblasts: create the matrix
• Fibrocytes: maintain the matrix
• Osteoclasts: break the matrix down for remodeling

Question 18

True or False: Adipose cells are common in some tissues but rare in others.

Answer 18

True.

Question 19

What is the primary function of mast cells?

Answer 19

Release heparin, histamine, and proteolytic enzymes in response to injury.

Question 20

What is the difference between fixed and wandering macrophages?

Answer 20

• Fixed: stay in position in connective tissue
• Wandering: move by amoeboid movement

Question 21

What is primary union in skin repair?

Answer 21

Edges of wound are close together; wound fills with blood, clot forms, and inflammatory response occurs.

Question 22

What is the significance of granulation tissue in wound healing?

Answer 22

Replaces clot; composed of fibroblasts, collagen fibers, capillaries.

Question 23

What is the structure of hyaline cartilage?

Answer 23

Large amount of collagen fibers evenly distributed in proteoglycan matrix; chondrocytes in lacunae.

Question 24

Where is fibrocartilage typically found?

Answer 24

In areas of body where a great deal of pressure is applied, such as the knee, jaw, and between vertebrae.

Question 25

Define simple squamous epithelium.

Answer 25

Single layer of flat cells.

Question 26

What are the functions of simple cuboidal epithelium?

Answer 26

* Secretion and absorption in the kidney * Secretion in glands * Movement of mucus in bronchioles

Question 27

What characterizes stratified squamous epithelium?

Answer 27

Multiple layers of cells that are cuboidal in the basal layer and flatten toward the surface.

Question 28

What is the role of chemical mediators in inflammation?

Answer 28

Stimulate pain receptors and increase blood vessel permeability.

Question 29

What is edema?

Answer 29

Swelling due to fluid leaving capillaries during inflammation.

Question 30

What is the function of gap junctions?

Answer 30

Aid intercellular communication and coordinate function of cardiac and smooth muscle.

Question 31

What are the locations where keratinized epithelium can be found?

Answer 31

Mouth, throat, larynx, esophagus, anus, vagina, inferior urethra, and cornea.

Question 32

What is the structure of keratinized epithelium?

Answer 32

Multiple layers of cells that are cuboidal in the basal layer and progressively flatten toward the surface. Surface cells are dead.

Question 33

What are the functions of keratinized epithelium?

Answer 33

Protection against abrasion, caustic chemicals, water loss, and infection.

Question 34

What are the functions of cell connections?

Answer 34

Form permeability layer, bind cells together, provide mechanism for intercellular communication.

Question 35

Name the types of cell connections.

Answer 35

* Desmosomes * Hemidesmosomes * Tight junctions * Adhesion belt * Gap junctions

Question 36

What are the characteristics of smooth free surfaces of epithelium?

Answer 36

Reduce friction.

Question 37

What is the purpose of microvilli on epithelial surfaces?

Answer 37

Increase surface area for absorption or secretion.

Question 38

What is the function of cilia on epithelial surfaces?

Answer 38

Move materials across the surface.

Question 39

Where is simple columnar epithelium located?

Answer 39

* Glands * Some ducts * Bronchioles of lungs * Auditory tubes * Uterus * Uterine tubes * Stomach * Intestines * Gallbladder * Bile ducts * Ventricles of the brain

Question 40

What is the structure of simple columnar epithelium?

Answer 40

Single layer of tall, narrow cells; some have cilia or microvilli.

Question 41

What are the functions of simple columnar epithelium?

Answer 41

* Movement of particles out of the bronchioles by ciliated cells * Aids in the movement of oocytes through the uterine tubes * Secretion by glands of the stomach and intestine * Absorption by cells of the intestine

Question 42

Where is transitional epithelium located?

Answer 42

Lining of urinary bladder, ureters, and superior urethra.

Question 43

What is the structure of transitional epithelium?

Answer 43

Stratified; cells change shape depending upon the amount of distention of the organ.

Question 44

What are the functions of transitional epithelium?

Answer 44

Accommodates fluctuations in the volume of fluid in an organ or tube; protection against the caustic effects of urine.

Question 45

What are the functional characteristics of simple layering in epithelium?

Answer 45

Allows diffusion of gases, filtration of blood, secretion, absorption.

Question 46

What is the protective function of stratified layering in epithelium?

Answer 46

Protection, particularly against abrasion.

Question 47

What is the role of squamous cell shape in epithelium?

Answer 47

Allows diffusion or acts as a filter.

Question 48

What do cuboidal and columnar cell shapes in epithelium indicate?

Answer 48

Secretion or absorption; may include goblet cells that produce and secrete mucus.

Question 49

Where is pseudostratified columnar epithelium located?

Answer 49

* Lining of nasal cavity * Nasal sinuses * Auditory tubes * Pharynx * Trachea * Bronchi of lungs

Question 50

What is the structure of pseudostratified columnar epithelium?

Answer 50

All cells reach basement membrane; appears stratified because nuclei are at various levels.

Question 51

What are the functions of pseudostratified columnar epithelium?

Answer 51

* Synthesize and secrete mucus onto the free surface * Move mucus (or fluid) that contains foreign particles over the free surface and from passages