Skin and Sweat

Question 1

What is the role of the epithelia?

Answer 1

Protect the internal environment of the body and regulate the exchange of materials between the external and internal environment.

Question 2

Where are epithelial cells found?

Answer 2

In the skin, digestive tracts, mucous membranes of the mouth and reproductive system, kidneys and urinary system, respiratory system, and exocrine secretory glands.

Question 3

What are the five categories of epithelial cells and what are their function?

Answer 3

Exchange - gas
Transporting - movement of things in and out of body
Ciliated - large internal structure e.g nose, upper airways
Protective - skin and lining of cavities
Secretory - endocrine glands, sweat glands etc..

Question 4

What are the different structures of the skin?

Answer 4

Epidermis - top layer
Dermis - glands and hair roots & capillaries
Subcutaneous tissue/hypodermis with fatty cells and veins

Question 5

What are the functions of the skin?

Answer 5

Barrier function, temperature control, sensation, endocrine, active immune defense.

Question 6

What is the main cell type in the epidermis?

Answer 6

Keratinocytes

Question 7

What is the role of eccrine Sweat Gland?

Answer 7

Acts as temperature control - liquid on surface of skin cools the body down. Also releases toxins and ions that are not needed.

Question 8

How is vitamin D metabolized?

Answer 8

Cholesterol metabolite hit by UV radiation and breaks benzene rings on cholesterol molecules - get vitamin D (non active). Goes to liver - add hydroxyl group to vitamin D - stable - goes to kidney and get 1, 25-dihydroxyvitamin D3 - maintains calcium balance in the body.

Question 9

What is the biggest role of vitamin D in the body?

Answer 9

Facilitate absorption of calcium and phosphate across the gut.

Question 10

What is the role of melanin?

Answer 10

Absorb UV

Cleans up free radicals