TOB CL2 epithelium

Question 1

Main types of simple epithelium

Answer 1

1. Squamous
2. Cuboidal
3. Columnar
4. Columnar ciliated

Question 2

Function and examples of simple squamous epithelium

Answer 2

Allow materials exchange via filtration & diffusion ( passive), secrete lubricants

blood vessels, bowman’s capsule, alveolus

Question 3

Function and examples of simple cuboidal epithelium

Answer 3

absorption, secretion

salivary glands, pancreas, PCT, DCT

Question 4

Function and examples of simple columnar epithelium

Answer 4

high absorptive, secretion

intestines, gallbladder, duodenum

Question 5

Examples of simple columnar ciliated epithelium

Answer 5

uterine wall

Question 6

Function and examples of pseudostratified epithelium

Answer 6

absorption, secretion

respiratory tract - trachea with cilia
epididymis - with sterocilia

Question 7

Types of stratified epithelium

Answer 7

1. Squamous
2. Cuboidal
3. Columnar

Question 8

Function and examples of stratified squamous epithelium

Answer 8

protection - physical abrasion, chemical injury, water loss

keratinised - dry epidermis
non-kertinised - keep moist - mouth, oesophagus, anus, vagina

Question 9

Function and examples of stratified cuboidal epithelium

Answer 9

protection, excretion

sweat gland, salivary gland, mammary gland

Question 10

Example of stratified columnar epithelium

Answer 10

urethra

Question 11

Function and example of transitional epithelium

Answer 11

high level of distention - transition, withstand toxicity

urinary bladder
urine present, cell stretch out, flatten
bladder empty, cell is round-shaped

Question 12

Types of epithelium ( in terms of location )

Answer 12

covering
- internal - tubes/tract - respiratory & digestive / body cavity - peritoneal, pericardial, pleural
- external - epidermis of skin

Glandular
-gland secretes secretions
-e.g. sublingual gland, sebaceous gland etc.

Question 13

Epithelial specialization (4)

Answer 13

microvilli, sterocilia, cilia , flagella

Question 14

Function and locations of microvilli

Answer 14

Increase SA for absorption & secretion

intestine, kidney

Question 15

Function and locations of sterocilia

Answer 15

Increase SA for absorption & secretion, elongated, distal branching, immotile

epididymis

Question 16

Function and locations of cilia

Answer 16

elongated, motile, move materials over the surface

respiratory epithelium, uterine wall

Question 17

Function and locations of flagella

Answer 17

move forward

spermatozoa

Question 18

Cell Junction parts and functions ( 5)

Answer 18

Tight junction
- close off intercellular space
- control movement of membrane

Zonula adherens
- linking point of actin filaments of adjacent cells
- stabilizes the tight junction

Desmosomes
- strong intermediate filaments
- strengthen tissues - high tensile strength

Gap junction
- exchange ions, metabolites, regulatory molecules

Hemidesmosomes
- basal epithelium to basal lamina

Question 19

What is the disease cause as pathogen targets tight junction ? (2)

Answer 19

Enterotoxin - binds to claudins - breakdown tight junction - watery diarrhea - food poisoning

House dust mites- inhalation - fecal pallets destroy tight junctions in respiratory epithelium - asthma

Question 20

Psoriosis

Answer 20

• inflammatory skin disease due to hyperkeratosis
• erythematous ( reddening) - scar on elbow, knee, scalp

Question 21

Darier disease

Answer 21

-autosomal dominant skin disease due to impaired desmosomes ( loss adhesion between epidermal cells) and abnormal keratinization