homeostasis (temeprature)

• There is no direct contact with the source gain or loss

• Occurs when hot or cold air passes over a body gain or loss

• Occurs from direct contact with heat source gain or loss

• Transformation of water from liquid to gaseous state loss only

42 is dangerous and 45 is deadly

body temperature rises, regulatory mechanisms cease, fatal if brain cells are affected

Loss of water ( sweating) reduces volume of blood plasma and vasodilation Vasodilation reduces blood flow resistance decreasing blood pressure and cardiac output

Chemical reactions are optimum at 37c if not; • Increase of temperature • Nerve malfunction • Change protein structure • Death

• Activity • External changes • Daily body cycle: low am and higher pm • Women higher in 2nd half on menstrual cycle

Carbohydrates, proteins, and lipids contain energy in chemical bonds that hold molecules together

muscle contraction, active transport and building molecules - when cellular respiration occurs for energy release

Cellular respiration creates heat Heat from stress and excercise; sympathetic nerves release noradrenaline - Increases metabolic activity Too cold metabolic rate slows, heat production cant replace lost heat