W2 - Epithelial Cell Types

Question 1

What is the main functions for simple epithelium and why?

Answer 1

Selective diffusion because only on cell layer thick and on surface

Question 2

Description of simple squamous cells

Answer 2

Flattened and irregular, forming a continuous surface

Question 3

Diffusion and tissue fluid transport occurs across the simple squamous epithelium, where do these processes occur in the body respectively?

Answer 3

Lungs/capillaries and pleural/pericardial/peritoneal cavity linings

Question 4

Why cannot the basement membrane be seen normally when staining the mesothelium with H+E? (simple squamous)

Answer 4

Has similar staining properties to collagen so cannot be distinguished

Question 5

Description of simple columnar cells

Answer 5

Tall and polar due to positioning of elongated nuclei

Question 6

Are the heights of columnar epithelial cells always the same?

Answer 6

No - it varies depending on site and function

Question 7

What is the function of the small intestine and stomach linings where simple columnar cells are found?

Answer 7

Absorption in SI and secretion in stomach

Question 8

In the endocervix lining, where are the nuclei typically positioned in the simple columnar cells?

Answer 8

They’re located basally

Question 9

What is the function of nonciliated simple columnar cells (nucleus usually at base)?

Answer 9

Secretion

Question 10

What do ciliated simple columnar cells (nucleus in middle) do in the female reproductive tract? (e.g. fallopian tubes)

Answer 10

Transports ovum from ovary to uterus

Question 11

Around how many cilia can be present on one cell?

Answer 11

~300

Question 12

Description of simple cuboidal cells

Answer 12

Square from side, polygonal from surface, circular and central nucleus

Question 13

What do simple cuboidal cells typically line?

Answer 13

Excretory, secretory or absorptive small ducts + tubules

Question 14

What does the nucleus of a simple cuboidal cell give a good estimation of?

Answer 14

Cell size (if can’t see boundaries clearly)

Question 15

What colour does a BM stain when using an azan stain on a collecting tubule in the kidney?

Answer 15

Blue

Question 16

Although simple pseudostratified columnar epithelium appear to have more than one cell layer, what characteristic means that it is definitely simple?

Answer 16

The fact that every cell rests on the basement membrane

Question 17

Simple pseudostratified cells are usually polar, why?

Answer 17

Nuclei are disposed at varying levels but usually the basal 2/3rds of the cell

Question 18

Are most cells in the simple pseudostratified columnar epithelium ciliated or nonciliated?

Answer 18

Ciliated

Question 19

What is the difference between true stratified and pseudostratified cells? (polarity, layering and ciliation)

Answer 19

True - non polar, multilayered and nonciliated, Pseudo - polar, single layer and ciliated

Question 20

Where can you find pseudostratified columnar epithelium?

Answer 20

In the respiratory epithelium in the bronchus

Question 21

What is the main functions for stratified epithelium and why?

Answer 21

Protective function as multilayered so suited to dealing with abrasion

Question 22

What may stratified epithelium be permeable to?

Answer 22

Water and small molecules

Question 23

The stratified squamous epithelium that continuously matues from cuboidal base layer to flattened surface layer is in what layer of the skin?

Answer 23

Eepidermis

Question 24

What two characteristics of stratified squamous tissue helps it to withstand abrasion?

Answer 24

Lots of cell junctions and keratin cytoskeleton

Question 25

Give 3 examples of areas where stratified squamous epithelium is found

Answer 25

Vagina, oesophagus and oral cavity

Question 26

What in the granular layer makes it waterproof?

Answer 26

Tight junctions

Question 27

How many cell layers does stratified cuboidal epithelium have and where found (+function)?

Answer 27

2-3, endocrine glands in mammals (so excretory, protective and secretory)

Question 28

Where is the only place stratified transitional epithelium is found?

Answer 28

Urinary tract

Question 29

What are two characteristics or transitional epithelium that make it suitable to the urinary tract?

Answer 29

Very stretchy and can withstand toxicity of urine

Question 30

What shapes are the basal, intermediate and surface layers of transitional epithelium?

Answer 30

Basal - cuboidal, intermediate - polygonal, surface - large and rounded (can have 2 nuclei)

Question 31

What happens to the shape of the intermediate and surface cells in transitional epithelium when stretched?

Answer 31

Become very flat