1. You go to the beach to swim on an extremely hot, sunshiny afternoon.
2. Describe two ways in which your integumentary system acts to preserve homeostasis during your outing.
The integumentary system preserves homeostasis in the body by regulating temperature and water loss on a hot day. The body temperature is kept stable by the production of sweat, which cools the body as it evaporates on the skin's surface. The sweat glands can release between one and two liters of water per hour (The Integumentary System). In hot weather, up to four liters of water can be lost per hour by a combination of sweating and evaporation. Exocrine sweat glands are controlled by the sympathetic nervous system, and occur all over the body. They open to the skin surface through the pores. Apocrine sweat glands are larger, and occur in the armpits and groin areas. They produce a solution that bacteria act upon to produce body odor. Blood vessels in the skin dilate to allow heat loss from the body and help it stay at normal temperature. Sweat gland function and vasodilation/vasoconstriction are controlled by the hypothalamus. It responds to heat and cold receptors located in the skin.
3. Distinguish clearly between first-, second-, and third-degree burns.
First-degree burns affect only the outer layer of the skin, the epidermal layer (Berkow, Beers and Fletcher, 1997, 1336-1338; First-Degree, 2003). The burn site is dry and red, and the burn is painful, but there is no blistering of the skin. The skin at the burn site will be painful to touch, and the pain may last for 48 to 72 hours. The skin may peel a few days later, and the epidermal layer regrows to cover the layers below. A new layer of epidermis will grow quickly from the base of s superficial burn, and leave little or no scarring. An example of a first-degree burn is a mild sunburn, or a sudden, short burst of heat. There is usually no long-term skin damage from firs...