Integumentary system Flashcards
Whats the Integumentary system?
The integumentary system is an organ system consisting of the skin, hair, nails, and exocrine glands. The skin is only a few millimetres thick yet is by far the largest organ in the body. The average person’s skin weighs 10 pounds and has a surface area of almost 20 square feet.
Whats the skins three main functions?
protection, regulation and sensation.
Whats the primary function of skin?
The primary function of the skin is to act as a barrier. The skin provides protection from: mechanical impacts and pressure, variations in temperature, micro-organisms, radiation and chemicals.
The skin regulates body temperature via sweat and hair, and changes in peripheral circulation and fluid balance via sweat. It also acts as a reservoir for the synthesis of Vitamin D.
The skin contains a network of nerve cells that detect and relay changes in the environment. There are separate receptors for heat, cold, touch, and pain.
How does the skin protect from invasion?
The skin covers the whole body and protects it from physical damage, microbe infection and dehydration. It is difficult for microbes to penetrate the skin’s dry, dead outer cells. In addition the sebaceous glands produce oils which also help to kill microbes.
Whats adipose fat?
Beneath the dermis is a fat layer
You can survive for only one day on stored glycogen. With fat, you can survive for weeks.
Fat is made when excess food is eaten. Stored fat is used for energy when food is lacking.
How does the skin synthesise vitamin d?
Human skin gets the vitamin D it needs by producing large amounts of it when your bare skin is exposed to sunlight. The part of the sun’s rays that is important is ultraviolet B (UVB).
However, you can get vitamin D from your diet
When is sun bad?
Exposure to too much UVA and B can cause skin cancer.
UVB = Burns
UVA = Tans
The role of the hypothalamus in thermoregulation:
Your hypothalamus is a section of your brain that controls thermoregulation. When it senses your internal temperature becoming too low or high, it sends signals to your muscles, organs, glands, and nervous system.
Whats the normal body temp?
37 degrees c
Describe the process of homeostasis and temperature control if your body temperature rises:
1) Normal body temperature (37 degrees C)
2) Body temperature rises above normal
3) Nervous system signals dermal blood vessels to dilate and sweat glands to secrete
4) Body heat is lost to its surroundings
5) Body temperature drops toward normal
Describe the process of homeostasis and temperature control if your body temperature decreases:
1) Normal body temperature (37 degrees C)
2) Body temperature drops below normal
3) Nervous system signals dermal blood vessels to constrict and sweat glands to remain inactive
4) Body heat is conserved
5) Body temperature rises toward normal
What are some ways your body will cool down if your hot?
- Vasodilation
- Sweating
- Pilorelaxation
- Stretching out
What are some ways your body will heat up when cold?
1) Vasoconstriction
2) Shivering
3) Piloerection
4) Curling up
Define vasodilation
Arterioles dilate (enlarge) so more blood enters skin capillaries and heat is lost
Define vasoconstriction
Arterioles get smaller to reduce blood going to skin: keeping core warm
