Skin

1.

SKIN

2.

Lesson objectives
To understand the structure and
functions of skin

3.

Lets think!
Why do people with light skin suffer
from sunlight more than people
with dark skin ?

4.

Functions of the skin
Covers and protects from germs,
dehydration, injury.
Regulates body temperature
Manufactures vitamin D
Excretes excess water and salts by sweat
Protects from UV radiation

5.

Structure of the skin

6.

Skin has three layers:
Epidermis
2. Dermis
3. Hypodermis
1.

7.

1. Epidermis
Very top layer.
Contains melanin
pigments for
protection from UVlight.
Made up of dead skin
cells.
Protects from viral
and bacterial invasion.
Protects from water
loss.

8.

9.

2. Dermis
Has receptors to
feel temperature,
pain, pressure.
Blood vessels.
Muscles.
Hair follicles.
Sebaceous and
sweat glands

10.

3. Hypodermis
Made up of FAT that store
energy and keeps body heat.
Connects the integumentary
system to muscle

11.

12.

Lets review the lesson

13.

Interesting facts about skin
One Square Centimeter of Skin Contains:
Skin is the largest organ in the body
(~2m²)
3,000,000 cells.
10 hairs.
700 sweat glands.
200 nerve endings to record pain.