Tissues — Epithelium Flashcards

1
Q

epithelial characteristics

A

free surface, closely aggregated cells, avascular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

domains

A

apical, lateral, basal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

surface specialization of apical

A

microvilli, sterocilia, cilia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

microvilli

A

function to increase surface area; contains acting, actin-binding proteins (fibrin and fascin), lateral anchoring proteins (minimyosin), amorphous apex (villin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

microvilli locations

A

GI tract and kidneys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

stereocilia

A

function to increase surface area; long microvilli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

stereocilia locations

A

epididymis (absorption) and each cochlea (sensory receptors)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

cilia

A

aids in movement; transports materials along surface; core is axoneme: 9+2 microtubules, basal body 9+0 triplets lacking central pair

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

cilia locations

A

respiratory tract and oviduct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

cell junctions (lateral domain)

A

tight, anchoring, communicating (gap)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

tight junctions—zonula occludens

A

belt-like junction; seal or zipper; virtually impermeable; prevents diffusion blocking paracellular pathway; occudens and claudins are the two main proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

zonula occludens locations

A

stomach (cells with secretory role) and kidney (cells with absorptive role)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

anchoring junctions—zonula adherens

A

connects actin filaments of two cells; contains actin-binding proteins, peripheral protein catenin which is Ca2+ dependent, and transmembrane protein cadherin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

anchoring junctions—madula adherens

A

connects intermediate filaments of two cells; mechanical strength; intracellular plaque; contains transmembrane protein cadherin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

madula adheren locations

A

skin and muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

communicating (gap) junction

A

channel; 2 connexons each with 6 protein subunits called connexions; transport of small ions and molecules occurs; “puzzle pieces”

17
Q

gap junction locations

A

epithelia, cardiac and smooth muscle, embryonic tissues

18
Q

cell junctions (basal domain)

A

focal adhesions and hemidesmosomes

19
Q

focal adhesions

A

connects actin cytoskeleton to extracellular matrix; actin-binding proteins, peripheral protein (talin), transmembrane protein (integrin which is Ca2+ independent)

20
Q

hemidesmosome

A

connects intermediate filaments cytoskeleton to extracellular matrix; intracellular plaque; transmembrane protein (integrin)

21
Q

epithelium classification (# layers, shape, surface modification)

A

simple means single layer; stratified means more than one layer; pseudostratified is unorganized

squamous means flat; cuboidal means length and width are equivalent; columnar means column

surface modifications meaning they can be ciliated or non-ciliated

22
Q

simple squamous epithelium

A

lining of vascular system, lining of body cavities, kidneys (bowman’s capsule), lung (respiratory spaces)

function as a barrier and in diffusion (O2, CO2)

23
Q

simple cuboidal epithelium

A

kidney (tubules), germinal epithelium of ovaries, thyroid follicles, various ducts ( glands)

function as a barrier, in secretion (thyroid), absorption (kidneys)

24
Q

simple columnar epithelium

A

GI tract and gallbladder (non-ciliated), oviduct (ciliated type)

functions in absorption, secretion, lubrication, and transport

25
Q

pseudostratified columnar epithelium (ciliated and non-ciliated)

A

ciliated: trachea and bronchi; function in protection and movement (mucus)

non-ciliated: epididymis (absorption) and prostate

***stereocilia

26
Q

stratified squamous epithelium

A

keratinized (skin, epidermis, contains keratin, dead) and non-keratinized (oral cavity, esophagus, vagina)

functions as a barrier and protection

27
Q

stratified cuboidal epithelium

A

sweat gland ducts and some exocrine glands

28
Q

stratified columnar epithelium

A

large ducts of glands, parotid salivary, submandibular

29
Q

transitional epithelium (urothelium)

A

urinary system, ureter, bladder, kidneys (pelvis and calyces)

functions as a barrier and protection

30
Q

glandular epithelium

A

formed as a result of epithelial tissue invagination

31
Q

exocrine glands — secretion methods

A

holocrine, apocrine, merocrine

32
Q

holocrine

A

cell destruction (apoptosis), whole cell content is released, cell sacrifices itself to deliver product

ex. sebaceous gland

33
Q

apocrine

A

apical cytoplasm pinching, releasing of vesicles

ex. mammary glands

34
Q

merocrine

A

exocytosis; doesn’t sacrifice anything; most common; 3 types—serous, mucous, mixed

ex. goblet cells, pancreas

35
Q

merocrine —serous

A

product thin, watery, protein-rich secretion; euchromatic nucleus (active cell), dark secretory granules, lots of RER; stains dark; ex is pancreas and parotid salivary gland

36
Q

merocrine —mucous

A

produce mucins (carbohydrates attached to protein core; heterochromatic nucleus (inactive cell), pale secretory granules, little RER; stain pale; important for protection and lubrication; ex are brunner’s glands and goblet cells

37
Q

merocrine —mixed

A

seromucous glands; mucous cells are tubules, serous cells are serous demilunes (half-moon shaped); ex is submandibular salivary gland

38
Q

exocrine glands —secretory part

A

alveolar or acinar (serous), tubular (mucous), tubuloalveolar (mixed)

39
Q

myoepithelial

A

surround acinar and contract gland in effort to delivery product (weakly contractile)