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Flashcards in epithelial tissues Deck (23)
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1
Q

what are the 4 types of tissues in a human body?

A

epithelium
connective
nervous
muscle

2
Q

describe epithelium

A

diverse structural arrangement depending on location and function of tissue

3
Q

what are the common functions of epithelial tissues?

A
lines all body surfaces
lines all tubes and cavities
-digestive system
-resp system
-cvs
barrier function
-boundary between different environments
-all substances entering and leaving body pass through epithelium
4
Q

what are the common structural features of epithelial tissues?

A

continuous sheets of cells
tightly bound together
polarised

5
Q

how does being tightly bound benefit?

A

protection against microbial invasion

provide opportunity to regulate movement of substances

6
Q

what are tight junctions?

A

create impermeable seal between adjacent cells

prevents water leakage

7
Q

what are desmosomes?

A

strong junctions
anchor adjacent cells together
ensure epithelial tissues can stretch and maintain contact

8
Q

what are 4 additional functions of epithelial tissues?

A
physical protection
-skin & oral cavity
diffusion of gases, nutrients and waste between blood & surrounding tissues
absorption of nutrients
-GIT
secretion
-sweat, mucus, enzymes,hormones
9
Q

how are epithelial tissues classed?

A
  1. shape
  2. number of cell layers
  3. apical specialisations
10
Q

what are the 3 shapes of epithelial cells?

A

squamous
cuboidal
columnar

11
Q

what are the 2 numbers of layers?

A

simple-single layer

stratified- 2 or more layers

12
Q

what are the 3 apical specialisations?

A
microvilli
-increase apical SA
cilia
-movement of particulate matter
keratin
-strong protective apical layer
13
Q

describe simple columnar ciliated

A

function:

ciliary action facilitates transport of ovum from ovary to uterus

14
Q

describe pseudostratified columnar ciliated

A

function:

ciliary action propel surface layer mucus containing traooed particles towards pharynx

15
Q

what are goblet cells?

A

modified columnar epithelial cells
synthesise and secrete mucus
scattered throughout simple columnar epitheliums
resp/GIT

16
Q

describe stratified epithelia?

A

protection from mechanical abrasion
name shape at surface
cells mature from basal layer from continuously dividing stem cells
gradually migrate to surface and are shed as anucleate squames

17
Q

what is keratin?

A

enhances resistance to physical stress
epithelial cells accumulate keratin filaments as they mature
formation of tough, non-living surface layer
can be in stratified squamous epithelia

18
Q

what is transitional epithelium?

A

allows for expansion and stretch

only found in bladder

19
Q

describe stratified cuboidal

A

function:
secretory
location:
rare, some ducts and glands

20
Q

describe stratified columnar

A

function:
secretory and protective
location:
male urethra & lines some glands

21
Q

what is an ulceration?

A

break in continuity of epithelium

can be infections and non-infections

22
Q

what is oral squamous cell carcinoma?

A

dysplastic epithelial cells proliferate in an uncontrolled manner
destroy and incade adjacent tissues

23
Q

what is a carcinoma?

A

malignant tumour arising from epithelial tissue
subclassified by tissue of origin
squamous cell originates from stratified squamous epithelium