Epithelium

Question 1

What is the very thin specialised epithelium of the blood vessels and vascular system called?

Answer 1

Endothelium

Question 2

Found on epithelial cells:

What are the finger like projections that increase surface area for absorption called?

What moves mucus and other matter along the length of the epithelium?

Answer 2

Microvilli

Cilia

Question 3

… are found lining the trachea, Vas Deferens and the oviduct.

Neither … or … are found in blood vessels, small endocrine ducts, lung alveoli, skin or oesophagus.

… are found lining the gastrointestinal tract and the nephrons of the kidney.

Answer 3

Cilia

Microvilli or cilia

Question 4

A SINGLE later of epithelial cells is known as…

Answer 4

Simple

Question 5

A common feature of epithelial cells is…

Answer 5

ABSENCE of blood vessels!

Question 6

In a pseudostratified epithelium…

Answer 6

ALL cells are in contact with the basement membrane.

Question 7

What functions are carried out by epithelia?

Answer 7

Sensory perception 
Absorption 
Secretion 
Transport 
Protection

Question 8

The principle cells of the liver are…

What is one of their functions?

Answer 8

Hepatocytes

Metabolism, storage, secretion

Question 9

What are the mucus secreting cells of the gastrointestinal tract and airways called?

Answer 9

Goblet Cells

Question 10

What protein is deposited at the surface of the skin epithelium to form a protective barrier?

Answer 10

Keratin!

Question 11

What best describes the epithelium of the skin?

Answer 11

Stratified squamous

Question 12

Pseudostratified epithelium is found in the… and …

Simple columnar epithelium is found in the…

Answer 12

Vas Deferens, lining the bronchus

Oviduct

Question 13

What is polarity?

Answer 13

Presence of an apical surface (free) and a basal surface.

Uneven distribution of organelles and membrane proteins!

Question 14

What does avascularity mean?

Answer 14

There are NO blood vessels in the epithelium as there is NO space for them between closely packed cells.

Question 15

How do epithelial cells receive nutrients and O2?

Answer 15

Nutrients are delivered by diffusion from blood vessels running in connective tissue which is BELOW the epithelium.

Question 16

What specialised structures are present on the apical surface of epithelial cells?

examples of where they are they found?

Answer 16

Microvilli - digestive tract

Cilia - trachea

Question 17

Function of microvilli + cilia?

Answer 17

M - increase surface area by increasing the absorptive capacity by 20x

C - help to move materials (mucus, eggs)

Question 18

Where is simple squamous epithelial tissue found?

What is its function?

Answer 18

In the lung alveoli

Allows material to pass by diffusion and filtration in sites where protection is NOT important!

Question 19

Where is keratinised stratified squamous epithelial tissue found?

What is its function?

What is the loose purple structure you can see on it?

Answer 19

Epidermis of the skin

Protection from mechanical + chemical damage

Keratin!

Question 20

What is the mode of secretion for Merocrine glands?

Answer 20

Secretion by exocytosis (sweat glands)

Question 21

What is the mode of secretion for Apocrine Glands?

Answer 21

A portion of plasma membrane BUDS off the cell which contains the secretion (mammary glands)

Question 22

What is the mode of secretion for Holocrine Glands?

Answer 22

The ENTIRE cell disintegrates to secrete it’s product! (Sebaceous glands)