BIO1000 – Human Biology
January 12, 2012
Part 1 - Regulates your body temperature when you are outside on a cold winter day. When it is cold outside and the temperature drops, your body thermo receptors detect the drop and send signals to the hypothalamus. Neurons also send signals to smooth the walls of the blood vessels to make them contract, which creates a narrowing in the blood vessel also known as “vasoconstriction”. What vasoconstriction does is that it slows down and decreases blood flow to your capillaries near the surface and helps your body retain the heat that you do have in order to keep your body warm. Pilomotor response is when the temperature drops outside and the body hair stands on end. This happens when muscles that are smooth become stimulated in order to contract, which then in turn creates a layer of air close to the skin which in return reduces the loss of heat from your body. If all responses don’t work, your body steps up and send signals to your skeletal muscle contractions which results in shivering to stay warm. When you are shivering, it contracts your muscles ten to twenty times per second with results of your body boosting heat throughout your body to keep you warm. If you have severe exposure to cold, this can lead to a hormone driven response that takes and speeds up the cell metabolism. This occurs in the adipose tissue which is also known as “the brown fat”. Adults do not have much brown fat unless they are cold adapted however babies that do not shiver have the brown fat in their armpits and neck areas. After your body does everything to keep you warm and fails, your body core temperature drops and can lead to hypothermia in which a few degree drop can lead to mental confusion. If you have more of a temperature drop, and your body cannot handle it, this can lead to coma or even death. Part 2 - Regulates Osmolarity, or solute concentration, of the blood in response to a...