Responses Flashcards
(20 cards)
Tropism
Directional growth response to a stimuli
Nastic Response
A response to a stimulus which is independent of the direction of the stimulus
Taxes
Movement of a whole organism towards/away from a stimulus coming from one direction
Kinesis
Rate of movement in an animal is affected by the intensity of the stimulus
Photo
Response to light
Geo
Response to land/gravity
Thermo
Response to temperature
Thigmo
Response to touch/contact
Hydro
Response to water
Chemo
Response to chemicals
Rheo
Response to water current
Niche
Combination of habitat, adaptations and and organisms role
Auxin + Example
Hormone that elongates cells example: towards light and ground in a plant
Photoperiodism
regulation of seasonal activity by day length or photoperiod (amount of light)
Long Day Plants
Requires Pfr to flower, short nights are needed to ensure there is some Pfr left over
Short Day Plants
Requires Pr to flower, long nights are needed to ensure enough Pfr is converted to Pr
Day Neutral Plants
Not affected by day length, may be affected by temperature
Phytochrome
A pigment which permeates flowering, germination and growth in plants
Pr(phytochrome red)
absorbs red light only, 660nm
Pfr(phytochrome far red)
absorbs far red light only, 725nm
