-
What is the function of hair & hair follicles?
protects the skin & reduces the rate at which body heat is lost
-
What is a characteristic found in all mammals?
hair
-
What is Hair?
a strand of dead highly keratinized cells that don't flake off
-
Where is the Hair anchored & extends out of?
The hair is anchored at the root in the dermis & extends out of skin as a shaft
-
What does the shape of the shaft determine?
- the shape of determines the type of hair
- - very curly hair = flat & ribbon-like
- - wavy hair = oval
- - straight hair = perfectly round
-
What are the 3 layers the shaft is composed of?
cuticle, cortex, & medulla
-
Why do animals have fur and humans do not?
humans do not have fur because skin is also a sense organ & heavy hair coats reduce the amount of evaporation
-
What is hair follicles?
the root of the hair & the portion of hair embedded in the skin
-
What is located deep into the dermis?
hair bulb
-
What does the hair bulb contain?
nerve endings & blood vessels.
-
What are hair follicles associated with?
sebaceous glands & arrector pili muscle
-
What is the rate hair grows at?
rate of 2mm per week & under growth cycles of growth & rest which also induces shedding. the longer the growth cycle the longer the strand in general.
-
What is sebaceous glands?
commonly called oil glands that have an oily substance called sebum found throughout the body except palms & soles of feet.
-
What does the sebum do?
softens & lubricates hair, prevents skin from cracking, kills bacteria, and reduces water loss.
-
What are the glands influenced by?
sex hormones
-
What is holocrine secretion?
this excretory gland releases the subum when the glabdular cells become too full of product & burst.
-
What is sweat glands?
helps to reduce body heat
-
What is another name for sweat glands?
sudoriferous glands
-
Where are sweat glands found?
in all skin surfaces except nippes & external genitalia
-
What is sweat?
water, salts, & metabolic waste filtrated from blood by secretary cells.
-
What are the 2 type of sweat glands?
Eccrine & Aprocurine glands
-
What are Eccrine Glands?
produce true sweat, opens at a pore (not readily visible)
-
What are aprocrine glands?
larger than eccrine & produce a mixture of sweat, fatty substances, & proteins. This gland is what causes body odor, respiond to hormones, foreplay, and menstrual cycle changes
-
What are ceruminous glands?
produce ear wax
-
What are mammary glands?
produce milk
-
What are Nails?
enables us to pick objects or balance weight (toes). Nails are keratinized cells that originate at the root, rest on the nail bed, & form a free edge at the distal end of the fingers.
-
What is the active growth area of the nails?
the nail matrix forming the lunula (white crescent)
-
What do the nails do laterally?
the nail is protected nail folds (folded skin)
-
What is the specialized nail fold called and what does it project at?
the specialized nail fold is called the eponychium (cuticle) that projects at the proximal end.
|
|