Epithelial Tissue

Question 1

Epithelial tissue has two forms:

Answer 1

1. covering and lining epithelium

2. glandular

Question 2

ET covers

Answer 2

walls/organs of the closed ventral body cavity

Question 3

ET lines

Answer 3

cavities

Question 4

ET lining/covering examples:

Answer 4

digestive, urogenital, respiratory

Question 5

ET glandular tissue:

Answer 5

fashions the glands of the body

Question 6

What are the functions of the ET boundary (6)?

Answer 6

1. protection
2. absorption
3. filtration
4. excretion
5. secretion
6. sensory receptor

Question 7

What are the special characteristics of Epithelium (5)?

Answer 7

1. polarity
2. specialized contacts
3. supported by connective tissue
4. avascular but innervated
5. regeneration

Question 8

Classification– What does the first and second name indicate about the ET layer?

Answer 8

first name indicates the number of cell layers

second layer describes the shape of the cell

Question 9

What are the two first names for ET?

Answer 9

either simple (single layer) or stratified (multiple layers)

Question 10

Function of simple ET?

Answer 10

the thin layer is mostly for secretion, filtration, and absorption

Question 11

Function of stratified ET (provide example)?

Answer 11

common in areas of high abrasion where protection is needed

ex: skin surface and lining of mouth

Question 12

Squamous ET description:

Answer 12

flattened and scale like

Question 13

Simple squamous ET has what two coverings?

Answer 13

an inner covering: endothelium

a mid covering: mesothelium

Question 14

Purpose of ET endothelium:

Answer 14

the inner covering provides a slick, friction-reducing lining

ex: blood vessels and heart

Question 15

What is the purpose of ET mesothelium (provide where it is most commonly found)?

Answer 15

the mid covering lines ventral body and covers organs

ex: found in serous membranes

Question 16

Simple cuboidal description:

Answer 16

the cells are box like and are as tall as they are wide

Question 17

Function of simple cuboidal (provide example):

Answer 17

secretion and absorption

ex: kidney tubules, wall of small glands, and ovary surface

Question 18

Simple columnar description:

Answer 18

the cells are a tall layer that is closely packed

Question 19

Function of simple columnar:

Answer 19

absorption and secretion (mainly of enzymes and mucus)

Question 20

Where can you find simple columnar (both nonciliated and ciliated)?

Answer 20

NONCILIATED: digestive tract, gallbladder, glands

CILIATED: small bronchi, uterine tubes, some regions of the uterus

Question 21

What is a pseudostratified columnar layer?

Answer 21

they vary in height, giving the impression of multiple layers

ex: trachea

Question 22

How do you classify stratified layers?

Answer 22

distinguish the top layer aka the apical layer

Question 23

The top of the layer is called the apical layer, the bottom layer is known as

Answer 23

the basal layer that holds basement cells

Question 24

Dead cells are at which point of the stratified layer?

Answer 24

the apical layer

Question 25

Newly regenerated cells are found...

Answer 25

at the basal layer

Question 26

Stratified squamous description:

Answer 26

the free surfaces (apical layer) is squamous, while the remaining layers are cuboidal or columnar

Question 27

Where can stratified squamous layers be found?

Answer 27

places subjected to wear and tear

Question 28

Where can stratified cuboidal layers be found?

Answer 28

RARE-- found in mostly ducts or large glands (mammary glands and sweat glands)

Question 29

Where can columnar stratified be found?

Answer 29

LIMITED-- found at transition areas or junctions between two other types of epithelia ex: pharynx, male urethra, lining of glands

Question 30

Stratified columnar description:

Answer 30

the free surface (apical layer) is columnar, they remaining layers are cuboidal

Question 31

Transitional epithelium description:

Answer 31

apical cells are dome-shaped or squamous like, resembles stratified squamous or stratified cuboidal; basal cells are cuboidal or columnar cells overlap for the purpose of stretching

Question 32

Function of transitional epithelium:

Answer 32

for areas that need to readily stretch ex: urinary organs (uterus, bladder, urethra)

Question 33

Gland consists of one of more cells that...

Answer 33

make and secrete a particular product

Question 34

Secretion description:

Answer 34

an aqueous fluid that contains proteins | * can also be lipid/steroid rich

Question 35

Secretion definition:

Answer 35

an active process where glandular cells obtain substances from the blood and chemically transform and discharge the product

Question 36

Glands are either internal or external also known as...

Answer 36

endocrine and exocrine respectively

Question 37

How are glands classified (2)?

Answer 37

1. whether internal/external | 2. number of cells-- multicellular or unicellular

Question 38

Where are unicellular glands?

Answer 38

scattered within epithelial sheets

Question 39

How are multicellular glands formed?

Answer 39

invagination: inward growth of epithelial sheet into underlying connective tissue

Question 40

Endocrine glands are ductless and produce...

Answer 40

hormones

Question 41

Exocrine glands [...] products onto [...] or into [...].

Answer 41

secrete; body surfaces (skin); cavities

Question 42

Unicellular exocrine glands secrete

Answer 42

directly

Question 43

How do multicellular exocrine glands secrete?

Answer 43

via epithelium-- walled duct

Question 44

What are two types of unicellular exocrine glands? What is the one thing they ALL produce?

Answer 44

1. mucous 2. goblet cells produce mucin

Question 45

What is the mucin produced by mucous and goblet cells?

Answer 45

a complex glycoprotein that dissolves H2O when secreted this forms mucous

Question 46

Where can mucous and goblet cells be found?

Answer 46

along epithelial linings of intestinal and respiratory

Question 47

What two parts make up the multicellular exocrine glands?

Answer 47

1. duct | 2. secretory unit (acinus)

Question 48

What is a secretory unit?

Answer 48

secretes substance

Question 49

Multicellular glands can be classified as either simple or compound. What's the difference?

Answer 49

simple-- unbranched duct | compound-- branched duct

Question 50

What are the 3 modes of secretion?

Answer 50

1. merocrine 2. holocrine 3. apocrine

Question 51

Pancreas, sweat glands, and salivary glands are what type of glands? What is their mode of secretion?

Answer 51

multicellular exocrine glands merocrine

Question 52

Oil glands are what type of glands? What is their mode of secretion?

Answer 52

multicellular exocrine glands holocrine

Question 53

Describe merocrine:

Answer 53

they secrete by exocytosis as they are produced "merely secrete"

Question 54

Describe holocrine:

Answer 54

accumulate products till they rupture "die for their cause"

Question 55

Describe apocrine:

Answer 55

ANIMALS ONLY: accumulate till filled; apical surface pinches off