A&P - Chapter 10 (Part 3) Flashcards
What are 7 functions of the skin?
- Protection*
- Sensation*
- Flexibility
- Excretion
- Hormone production
- vitamin D - Immunity
- Temperature regulation*
What kind of protection does the skin give? (3)
- A physical barrier to microorganisms
- Barrier to chemical hazards
- Protection agains excess UV exposure
What does the skin prevent?
Dehydration
What are 2 important contributors to the skin for protection?
- Keratin
- horny layer - Melanin
- pigmentation
What does keratin help defend? (4)
- Infection by microbes
- Harmful chemicals
- Cuts and tears
- Excessive fluid loss
What does melanin help defend?
UV rays from the sun
What does skin act as?
A sophisticated sense organ
What do somatic sensory receptors detect? (4)
Stimuli that permit us to detect…
- Pressure
- Touch
- Temperature
- Pain
Where is sensation mainly located?
In the dermis part
What do senses not adapt to?
Pain
- adapts to everything else
What do receptors serve as?
Receivers for the body
- keeping it informed of changes in the environment
What do meissner’s corpuscles detect?
Light touch
What do pacinian corpuscles detect?
Pressure
How much heat is lost through the skin?
80%
Evaporation
The skins mechanisms of temperature regulation
- has a cooling effect
Regulation of sweat secretion
Heat loss through evaporation
Regulation of flow of blood close to the body surface
Heat loss through radiation
What are 4 accessory organs/structures of the skin?
- Hair
- Nails
- Skin glands
- Receptors
What does hair growth require?
Hair follicle
Where does growth of hair begin?
Hair papilla
Hair papilla
Small shaped clusters of cells at the base of the follicle
Hair root
Lies hidden in the follicle
What is the visible part of the hair called?
The shaft
What 3 structures are considered hairless?
- Lips
- Palms
- Soles
What is attached to the base of the hair follicle?
Arrector pili
What do contractions of the arrector pili cause?
Goose bumps
- hair standing on end
What are nails produced by?
Epidermal cells over ends of fingers and toes
What makes nails hard?
Keratin
What is the visible part of the nail called?
Nail body
Where does the root lay?
In a groove and it hidden by the cuticle
Lunula
Crescent shaped area nearest the root
