Tissues

Question 1

Describe the cellularity of epithelial tissue

Answer 1

composed almost entirely of cells; little extracellular matrix; cells are connected by intercellular junctions

Question 2

Describe the polarity of epithelial tissue

Answer 2

defined apical (top) and basal (bottom) surface

Question 3

Describe the attachment of epithelial tissue

Answer 3

attach to basement membrane

Question 4

What is basement membrane?

Answer 4

An acellular surface produced by epithelial and connective cells

Question 5

What are the two layers of basement membranes in epithelial tissues?

Answer 5

basal lamina and reticular lamina

Question 6

Is epithelial tissue vascular or avascular?

Answer 6

avascular

Question 7

What are important functions of epithelial tissue?

Answer 7

physical protection, selective permeability, movement/clearing, secretion, sensating

Question 8

What does the basal lamina secrete?

Answer 8

collagen, laminin, proteoglycans

Question 9

What does the reticular lamina secrete?

Answer 9

reticular fibers, fibronectin, glycoproteins

Question 10

tell me as much as you can about epithelial cell structure

Answer 10

refer to notes bestie

Question 11

Describe this function of epithelial tissue: Physical protection

Answer 11

protection from dehydration, abrasion, and physical, chemical, or biological agents

Question 12

Describe this function of epithelial tissue: Selective permeability

Answer 12

regulates the passage of certain molecules in or out of a certain region of the body; exchange: passive and transport: active or facilitated (ex. the lungs)

Question 13

Describe this function of epithelial tissue: movement/”clearing”

Answer 13

pushing of fluid or other material along a surface

Question 14

Describe this function of epithelial tissue: Secretion

Answer 14

release of materials (ex. sweat, saliva)

Question 15

Describe this function of epithelial tissue: Sensation

Answer 15

receptors connected to nerve endings that can detect light, chemicals, mechanical stimuli, cold/heat

Question 16

Desmosomes

Answer 16

Hold cells together

Question 17

What happens in exchange epithelia

Answer 17

leaky exchange epithelium allows movement through gaps between the cells (bulk filtration/ diffusion)

Question 18

What happens in transport epithelia?

Answer 18

tight junctions in a transporting epithelium prevent movement betweem adjacent cells (substances must instead pass through the epithelial cell)

Question 19

Clearing/moving epithelia are normally

Answer 19

ciliated; columnar
(microvilli- expand surface area)

Question 20

Examples of Sensory Epithelia

Answer 20

retina, cochlea

Question 21

How are Goblet cells an example of secretory epithelia?

Answer 21

secrete mucus into the lumen of hollow organs such as the intestine

Question 22

exocrine glands

Answer 22

secrete products through ducts; products enter “exterior”: intestinal lumen, skin surface

Question 23

endocrine glands

Answer 23

ductless; products enter body “interior”; direct secretion into bloodstream or interstitial fluid

Question 24

Merocrine

Answer 24

secretory products secreted by vesicular exocytosis (sweat, saliva)

Question 25

Apocrine

Answer 25

partial cellular breakdown; cytoplasm and vesicular contents secreted ( milk, under arm sweat)

Question 26

holocrine

Answer 26

entire cell lost with secretion; stem cells divide to replace lost cells (oil glands

Question 27

Where are you going to find intercellular junctions in epithelial tissue?

Answer 27

near their apical surface (this makes sense because they are the gatekeepers molecules have to go from apical to basal)

Question 28

In the ZO protein tight junction what binds to ZO1

Answer 28

occludin

Question 29

In the ZO protein tight junction what binds to ZO2

Answer 29

claudin

Question 30

In the ZO protein tight junction what binds to ZO3

Answer 30

JAM

Question 31

What are adhering junctions made from

Answer 31

actin

Question 32

adhering junctions are actin filament-based systems also known as...

Answer 32

zonula adherens

Question 33

Where are you likely to find adhering junctions?

Answer 33

basal layer

Question 34

microfilaments are made out of

Answer 34

actin

Question 35

Intermediate Filaments are made out of

Answer 35

Keratin and laminin

Question 36

Microtubules are made from

Answer 36

tubulin

Question 37

3 major types of cytoskeletal elements

Answer 37

microtubules, microfilaments, intermediate filaments

Question 38

intracellular proteins provide

Answer 38

structure and framework

Question 39

E-Cadherin

Answer 39

helps cells stick together (extracellular)

Question 40

Button desmosomes

Answer 40

tie cells together; flexible

Question 41

hemidesmosomes

Answer 41

tie cell to basal lamina

Question 42

Gap Junctions

Answer 42

allow transport between two cells without going through extracellular fluid; rapid communication between cells

Question 43

Gap junctions are made from how many sub-units

Answer 43

6

Question 44

the 6 subunits of a gap junction form a

Answer 44

hemichannel

Question 45

each hemichannel is called a

Answer 45

connexon

Question 46

each connexon is a

Answer 46

hexamer

Question 47

2 hemichannels make

Answer 47

1 gap junction