Unit 2 Key Area 4 Flashcards
Human body’s community of cells and the tissue fluid that bathes them.
Internal environment
Maintenance of body’s internal environment with tolerable limits by negative feedback control
Physiological homeostatis
Region of the brain containing a centre which regulates body temperature
Hypothalamus
Muscle or gland which preforms the body’s response to stimuli following receipt of signals from the nervous system
Effector
Structure which detects changes in body temperature
Thermoreceptor
Organism able to control its internal environment and be independent of its external environment
Regulator
Organism unable to control its internal environment and is dependent on its external environment
Conformer
Mechanism of homeostais whereby a change in a physiological factor triggers a response that counteracts the original change
Negative feedback
Animal which is able to regulate its body temperature by physiological means
Endotherm
Animal which is unable to regulate its body temperature by physiological means
Ectotherm
Outer layer and limbs of body which have a “superficial” body temperature of around 33 °C
Body shell
Vital organs of body normally at “deep body” temperature of around 37 °C
Body core
Process by which the bore of skin arterioles become narrower
Vasoconstriction
Process by which the bore of skin arterioles become wider
Vasodilation
Mechanism adopted by some conformers (unable to employ physiologial mechanisms) to maintain an optimum metabolic rate
Behavioural response
