SKIN
Skin
Location:
All over your body
Function:
Protect, keep moisture in, hold
your body together
1.
Skin is the largest organ of the
body, and the barrier between
the internal organs of the body
and the external environment.
2.
The skin is divided into 3 distinct
layers. From the outside in they
are the epidermis, the dermis, and
the subcutaneous tissues.
A. Epidermis: averages in thickness
about the width of the mark of a
sharp pencil. There are two distinct
types of cells in the epidermis-the
keratin-forming cells and the melaninforming cells. Melanin is the color
pigment in the skin.
B. Dermis: has rich nerve and
blood supply. The sebaceous,
or oil glands and the shorter
hair follicles originate in the
dermis.
C. Subcutaneous tissue: serves as a
receptacle for the formation and
storage of fat, and supports blood
vessels and nerves that pass the tissues
beneath to the dermis above.
3.
The nerve supply to the skin
consists of sensory nerves and
motor nerves.
A.
B.
Sensory nerves: alert the brain to
sensations of touch, temperature or
pain.
Itching is the one of the most
common problems with the skin; the
sensation is transmitted by the
sensory nerves.
C. Motor nerves: in the skin are under
the regulation of involuntary
sympathetic nervous system and
control sweat glands, tiny smooth
muscles in the skin, and the size of
small arteries in the skin.
D. Goose pimples are produced when
the tiny little muscles, called erector
pili muscles are stimulated are produce
a traction on the hair follicles to which
they are attached.
Hair Follicles in the skin are
derived from hair follicles of the
epidermis.
Can new hair follicles form after birth?


Different types of body hair is the result of
location on the body and the effects of external
an internal stimuli.
Hormones are the most influencing the various
types of hair growth.
True or False?





Shaving of excess hair on the extremities does
promote more rapid growth of course hair.
Massage is of no value in stimulating scalp hair
growth.
Hair can turn gray overnight.
The common type of baldness seen in middle-aged
men cannot safely be influenced by any type of
lotion, stimulation or medication— including
hormones.
Heredity is the greatest factor causing male baldness.
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