Definitions Chapter 15-15.3 Biology OCR A Level
Homeostasis maintenance of stable equilibrium within a narrow range inside the body
Negative feedback a change occurs in the body and effectors work to reverse the change
system
Positive feedback a change occurs in the body and effectors work to reinforce the change
system
Thermoregulation maintenance of a relatively constant core body temperature
Endotherms animals that use metabolic processes to thermoregulate (mammals/birds)
Ectotherms animals that use their surroundings to thermoregulate so are heavily dependent on environment
Hypothalamus region of the brain above the pituitary which contains osmoreceptors
Exothermic metabolic reactions that give out heat (respiration)
metabolic activities
Vasodilation when arterioles near the surface of the skin dilate forcing increased radiation
Vasoconstriction when arterioles near the surface of the skin constrict forcing decreased radiation
Homeostasis maintenance of stable equilibrium within a narrow range inside the body
Negative feedback a change occurs in the body and effectors work to reverse the change
system
Positive feedback a change occurs in the body and effectors work to reinforce the change
system
Thermoregulation maintenance of a relatively constant core body temperature
Endotherms animals that use metabolic processes to thermoregulate (mammals/birds)
Ectotherms animals that use their surroundings to thermoregulate so are heavily dependent on environment
Hypothalamus region of the brain above the pituitary which contains osmoreceptors
Exothermic metabolic reactions that give out heat (respiration)
metabolic activities
Vasodilation when arterioles near the surface of the skin dilate forcing increased radiation
Vasoconstriction when arterioles near the surface of the skin constrict forcing decreased radiation
