AP BIOLOGY

Detailed explanation-1: -Normally, the vessels that supply blood to the skin constrict or narrow in response to cold temperatures. This reaction, called “vasoconstriction, ” decreases blood flow to the skin, which helps to minimize heat loss from the warm blood and therefore preserve a normal internal or “core” temperature.

Detailed explanation-2: -Cutaneous vasoconstriction decreases skin blood flow and lowers skin temperature, thereby reducing the skin-to-air temperature gradient and the potential for heat transfer to the environment.

Detailed explanation-3: -Hypothermia is a medical emergency that occurs when your body loses heat faster than it can produce heat, causing a dangerously low body temperature. Normal body temperature is around 98.6 F (37 C). Hypothermia (hi-poe-THUR-me-uh) occurs as your body temperature falls below 95 F (35 C).

Detailed explanation-4: -When the body temperature falls, the blood vessels constrict, sweat glands don’t produce sweat, and shivering generates heat to warm the body. This causes heat to be retained the the body temperature to return to normal.