Lecture 3

Question 1

The most cellular tissue in the body is:

Answer 1

Epithelial tissue

Question 2

How are epithelial tissues divided?

Answer 2

Simple (one layer thick), or stratified (more than one cell layer)

Question 3

What are the shape possibilities of epithelial cells?

Answer 3

• squamous (flattened)
• cuboidal (equal dimension, cubes)
• columnar (taller than it is wide)

Question 4

List 5 characteristics of epithelial tissues:

Answer 4

• little intercellular matrix
• display free surfaces
• line body cavities, and cover body surfaces
• form secretory and excretory parts of glands
• they may be innervated

Question 5

Describe an apical domain

Answer 5

a surface of the cell that is in contact with a lumen (Ex: kidney tubule, glandular duct cells)

Question 6

Describe a basolateral domain

Answer 6

Cell surfaces are loced together by special junctional complexes with neighboring cells including the opposite surface of an apical domain.

Question 7

Epithelial tissues contain blood vessels (true/false)

Answer 7

FALSE

Question 8

List and describe the sites where epithelial tissue can be derived from:

Answer 8

• Ectoderm: skin epidermis and glands
• Endoderm: GI tract and glands
• Mesoderm: lining of blood vessels, mesothelium, Bowman’s capsule

Question 9

Describe the two layers of basement membrane:

Answer 9

• basal lamina is 50-80 nm thick, composed of collagen + glycoproteins, and is PAS +
• reticular lamina is in contact with connective tissue

Question 10

List three functions of the basement membrane:

Answer 10

• filtration barrier
• scaffold for embryogenesis and regeneration
• stabilization of tissue shapes

Question 11

What are the three possible surface modifications for epithelium

Answer 11

• cilia
• stereocilia
• microvilli (brush border)

Question 12

What is the main difference between highly keratinized and lightly keratinized cells?

Answer 12

highly keratinized cells lack a nucleuses in their surface layer of cells whereas lightly keratinized cells still have nucleuses in the outside layer of cells.

Question 13

When cells appear to be stratified but they are all actually in contact with the basal lamina this is called…

Answer 13

Pseudostratified

Question 14

Pseduostratified epithelium is a type of what class of epithelium?

Answer 14

Simple epithelium

Question 15

What is a signature characteristic of transitional epithelium?

Answer 15

There is a dome shaped surface of the cells that give the appearance of stratified epithelium

Question 16

Transitional epithelium is typically associated with what area of the body

Answer 16

The urinary tract (referred to as urothelium)

Question 17

Surface modifications are characteristic of which of the two domains?

Answer 17

Apical, cilia or microvilli

Question 18

Apical domains face:

Answer 18

Lumen or external environment

Question 19

Basolateral domains are characterized by:

Answer 19

• intercellular junctions

- cell surfaces are in contact with the basement membrane and surrounding lateral domains

Question 20

Where can you find simple squamous epithelium?

Answer 20

• Lining of lumens of ducts, vessels, and other tubular structures
• Walls of alveoli, Bowman’s Capsules, inner surfaces of membranous labyrinth and tympanic membrane

Question 21

Simple cuboidal epithelium can be found:

Answer 21

• Surface of ovary, pigmented epithelium of retina, kidney tubules, glands and ducts, terminal bronchioles, choroid plexus, and anterior capsile of lens of eye (7)

Question 22

You can find simple columnar epithelium in the:

Answer 22

• digestive tract (starting with stomach cardia)
• gallbladder
• excretory ducts of glands

Question 23

This type of tissue is found in the epidermis with connective tissue papillae

Answer 23

Heavily keratinized stratified squamous epithelium

Question 24

Non-keratinized stratified squamous epithelium is found in the

Answer 24

esophaus, vagina, lining of mouth, tongue, and part of the epiglottis

Question 25

This type of epithelium is found in adult sweat glands among other places and is seldom found.

Answer 25

stratified columnar epithelium

Question 26

Pseduostratified epithelium can be found in the:

Answer 26

- Trachea | - epididymis (with stereocilia)

Question 27

Urothelium is a type of which epithelium and is found where?

Answer 27

- transitional epithelium | - urinary system

Question 28

Epithelial tissue has 2 main functions, what are they?

Answer 28

- protections | - maintain concentration differences

Question 29

When epithelium is associated with secretion or absorption it is probably what kind of epithelium?

Answer 29

Pseudostratified or simple

Question 30

Simple columnar epithelium functions in primarily the:

Answer 30

- secretions of enzymes and mucous | - absorption of nutrients and fluids

Question 31

List the characteristics of microvilli (brush borders)

Answer 31

- non-motile - forms a uniform brush border across the apical membrane - increases the surface area of absorption - found in the intestinal epithelium and parts of the kidney tubules

Question 32

Describe the structure of microvilli

Answer 32

Microvilli have an actin filament core that extends into a network of cytoskeletal proteins under the apical membrane.

Question 33

Describe the structure of cilium

Answer 33

A cilium has 9 peripheral doubles and a central pair of microtubules that are an alpha and beta tubule.