Homeostasis Flashcards
Define homeostasis.
The maintenance of a constant internal environment within the body.
What is negative feedback?
Any change to the conditions in the system causes a response to reverse the change. e.g. sweating.
Define vasodilation.
The widening of blood vessels that causes more blood to flow in the skin capillaries, so more heat is lost from the body.
Define vasoconstriction.
The narrowing of blood vessels that causes less blood to flow in the skin capillaries, so less heat is lost from the body.
Define gravitropism.
Response in which parts of a plant grow towards, or away from, gravity.
Define phototropism.
Response in which parts of a plant grow towards, or away from, the direction from which light is coming.
Define auxin.
Plant hormone that affects the rate of elongation in shoots and roots, causing tropisms in response to stimuli.