Taxis/kinesis, tropism/nastic Flashcards
Tropism (Tropic)
Directional growth of a plant towards (+) or away (-) from a directional stimulus.
Nastic Movement (Nasty)
Non-directional movement of a plant in response to a stimulus.
Taxis (Tactic)
Directional movements of an animal towards (+) or away (-) from a directional stimulus.
Kinesis (Kinesis)
Non-directional movement of an organism in response to a stimulus, where the rate of turning (klinokinesis) and or speed (orthokinesis) depends on the intensity of the stimulus
Chemo
Chemical Stimulus.
For Example, the movement of a wasp towards an attractive odor such as beer is a positive Chemotactic movement.
Geo
Gravitational Stimulus.
For Example, The root of a plant growing with gravity (downward) is a positive geotropic movement.
Photo
Light Stimulus.
For Example, the shoot of a plant growing towards the sunlight is a positive phototropic movement.
Thigmo
Touch Stimulus
For Example, When a venus flytrap closes (in response to a fly) it is a positive thigmotropic response.
Hydro
Water Stimulus
For example, When a bear moves to water to have a drink it is a positive Hydrotactic movement.