Epithelial Tissues

Question 1

What are the 4 types of tissue in the human body?

Answer 1

Epithelium, Connective, Nervous, Muscle

Question 2

What is the main function of epithelial tissues?

Answer 2

To line body surfaces
external surfaces = skin
internal surfaces = tubes and cavities
Form a barrier between different environments

Question 3

What do tight junctions do?

Answer 3

Create an impermeable water-tight seal between adjacent cells

Question 4

What are desmosomes?

Answer 4

Strong anchoring junctions that hold cells together. Lots of desmosomes in the skin.

Question 5

What do desmosomes do?

Answer 5

Provide the tissue with strength. Allow tissue to stretch and maintain contact

Question 6

Name 5 functions of epithelium

Answer 6

1. Barrier function
2. Physical protection to mechanical abrasion
3. Allow diffusion of gases
4. Absorption of nutrients
5. Secretion of sweat, enzymes, hormones, mucus

Question 7

Name the 3 shapes of cells

Answer 7

Squamous, Cuboidal, Columnar

Question 8

What does psuedostratified mean?

Answer 8

Fake stratified - single layer of cells but looks like multiple layers of cells due to arrangement of nuclei

Question 9

Where is stratified transitional epithelium found?

Answer 9

In the bladder

Question 10

Name some of the apical specialisations that can be found on epithelium

Answer 10

Microvilli, Cilia, Keratin

Question 11

What do microvilli do?

Answer 11

Increase surface area to facilitate absorption

Question 12

What do cilia do?

Answer 12

Movement of particulate matter over surface of epithelium. Beating motion.

Question 13

What is the function of keratin?

Answer 13

Protective. Gives skin a waterproof and protective function. Keratin is a tough protein.

Question 14

What is oral squamous cell carcinoma?

Answer 14

Cancer of the epithelium in the mouth

Question 15

Define carcinoma

Answer 15

A malignant tumour arising from epithelial tissue

Question 16

What does epithelia rest on?

Answer 16

Basement membrane

Question 17

What happens in an ulceration in the mouth?

Answer 17

The epithelium breaks is disrupted and the barrier function breaks down

Question 18

What are goblet cells?

Answer 18

Specialised columnar epithelial cells that synthesise and secrete mucus

Question 19

Where would you find pseudo stratified ciliated columnar epithelium?

Answer 19

Trachea

Question 20

Where is simple cuboidal epithelium typically found?

Answer 20

Lining small ducts and tubules e.g. in the kidney

Question 21

Where is simple columnar epithelium typically found?

Answer 21

Absorptive surfaces e.g. small intestine

Question 22

Where is simple squamous epithelium typically found?

Answer 22

Lining the alveoli of lungs and lining capillaries. Very thin barrier -> good for diffusion

Question 23

What are the 3 ways in which epithelial cells can differ?

Answer 23

1. Shape of cells
2. Number of cell layers
3. Apical specialisations

Question 24

Where is stratified epithelia typically found?

Answer 24

At sites where their function is to protect against mechanical abrasion.

Question 25

What is the most commonly found stratified epithelia in the body?

Answer 25

Stratified squamous epithelium

Stratified cuboidal and stratified columnar epithelium are very rare