Unit 2 Skin Functions Flashcards
What are the functions of the skin?
- Protection
- Touch
- Temperature Control
- Healing Wounds
What are two ways the skin protects us?
- Epidermis provides a waterproof barrier to which keeps out microorganisms such as bacteria and fungi.
- Melanin protects us from UV radiation in sunlight
What 3 things can sensory nerves in the skin detect?
- Pressure
- Temperature change
- Pain
How does the skin aid in Vitamin D production?
Some skin cells produce a Vitamin D precursor (dehydrocholesterol) , which when exposed to sunlight creates an inactive form of Vitamin D (cholecalciferol).
In the liver and kidneys the inactive form is modifed and becomes active active Vitamin D (calcitriol).
How does the skin help with temperature regulation?
When the body temperature is above the set point, the nervous system tells structures in the skin and other organs to release heat.
When the body temperature is below the set point, the brain triggers different responses to the skin structures.
Explain how the body cools itself during physical exercise.
- Active muscles release heat, which is carried awy in the blood.
- The warm blood reaches the hypothalmus (in the brain) which controls the body’s temperature set point.
- Smooth muscle in the dermal blood vessels are signaled to relax and dilate (vasodilation)
More blood enters them
Some heat is released to,lower body temperature - The merocrine glands also become active to release sweat onto the skin surface
As liquid evaporates it carries heat away from the surface, cooling the skin
Explain how the body warms itself in a cold environment.
- The smooth muscle in the walls of the dermal blood vessels are stimulated to contract
Decreasing the flow of heat-carrying blood through the skin
Helps reduce heat loss - Merocrine sweat glands remain inactive, decreasing heat loss by evaporation
- Skeletal muscles can be stimulated throughout the body to contract slightly which i creases the rate of cellular respiration that releases heat
- Small groups of muscles may rhythmically contract with greater force, which causes the person to shiver, generating more heat
What is hypothermia?
When the body temperature falls below 95 degress.
What are the initial symptoms of hypothermia?
Shivering
Feeling of coldness
What are the symptoms of worsening hypothermia?
- Loss of coordination
- Stiffening muscles
- Confusion
- Fatigue
- Slow, shallow breathing
What is hyperthermia?
Core body temperature above 101 degrees
What are the initial symptoms of hyperthermia?
Skin becomes hot, dry and flushed
What are the symptoms of worsening hyperthermia?
- Weakness
- Dizziness
- Headaches
- Rapid, irregular pulse
How does the skin respond to a shallow wound?
Epithelial cells along the wound margin are stimulated to divide more rapidly.
Newly formed cells fill the gap of the wound
What is a deep wound?
A wound that extends into the dermis or subcutaneous layer.