Cell Biology II

Question 1

What are tissues?

Answer 1

groups of cells that have similar structure and perform similar functions

Question 2

Four types of tissues?

Answer 2

Epithelium
Mesenchymal OR connective tissue
Muscle
Nervous tissue

Question 3

Functions of epithelia? Examples for each?

Answer 3

Protection (epidermis)
Absorption/Secretion (GI tract)
Selective diffusion (walls of capillaries)
Glandular secretion (sebaceous glands)
Providing sensation (retina)

Question 3

What is epithelia? Accompanied by?

Answer 3

tissues that line or cover surfaces in the body, connective tissue (often)

Question 4

Epithelia vascular or avascular? Explanation?

Answer 4

Avascular; have high cell turnover and connective tissue that IS vascular

Question 4

What is polarity?

Answer 4

fixed segments of a cells border different from one another

Question 5

What is a lumen?

Answer 5

space contained within a tube or sphere

Question 6

What is the apical border?

Answer 6

Border facing the lumen

Question 7

What is the lateral border?

Answer 7

surface facing or attached to adjacent cells in the tissue

Question 7

What is the basal border?

Answer 7

surface adjacent to the underlying connective tissue matrix

Question 8

Epithelia layer definitions? One? Two or more?

Answer 8

Simple
Stratified

Question 9

Shape of epithelial cell?
Flat?
Cube-shaped?
Tall and skinny?

Answer 9

Squamous
Cuboidal
Columnar

Question 10

Where are simple squamous epithelium found? Example?

Answer 10

Where simple diffusion is required ex. walls of capillaries THINK: little cytoplasm so little room for organelles

Question 11

Where do simple cuboidal epithelium cells live? Example?

Answer 11

Line secretory surfaces and ducts that conduct secretions; ducts of small exocrine glands

Question 12

Simple columnar epithelium line? Example?

Answer 12

Secretory and/or absorptive surfaces; lining of the stomach THINK: Most cytoplasm most # of organelles

Question 13

Where are stratified squamous cells found? Trend amongst layers? Example? Apical layers are sometimes _____?

Answer 13

Where a lot of abrasion occurs; basal is thicker than apical; epidermis; keratinized

Question 14

Functions of stratified cuboidal cells? Example? Commonality?

Answer 14

Protects against chemical abrasion, contributes to secretion; mammary glands, RARE

Question 15

Where are transitional epithelium found? Example? Appearance?

Answer 15

Where stretching occurs; lining of bladder; apical layer is scalloped

Question 15

Functions of stratified columnar cells? Example? Commonality?

Answer 15

Secretion and protection; male urethra; VERY RARE

Question 16

Where are pseudostratified columnar epithelium found? Example? Why are the “pseudo”?

Answer 16

mucus secreting cells; trachea; basilar surface of EVERY cell touches basement membrane

Question 17

What are lateral modifications of the epithelia?

Answer 17

Desmosomes and gap or tight junctions

Question 18

Relationship between basilar surface and basement membrane?

Answer 18

ALWAYS fused

Question 19

What is the basement membrane a barrier against? Important for? Can act as ____.

Answer 19

malignant cells, angiogenesis (production of blood cells), filtration membrane

Question 20

Three apical modifications?

Answer 20

Microvilli, cilia, stereocilia

Question 21

Microvilli arrangement and function?

Answer 21

parallel (like a brush), contribute to absorption

Question 22

Difference between cilia and microvilli appearance?

Answer 22

Cilia are wider in diameter

Question 23

Function of cilia?

Answer 23

VERY motile, move mucus or other lumenal secretions

Question 24

Appearance and function of stereocilia?

Answer 24

Very long microvilli; absorption

Question 25

Are stereocilia motile?

Answer 25

NO