Response to stimuli Flashcards
What is a tropism?
A tropism is a directional growth response.
What is a stimulus?
A stimulus is a detectable change in the environment.
What is a taxes?
A movement towards or away from a directional stimulus.
What is kinesis?
An animal’s rate of movement or turning is affected by stimulus intensity.
What is behaviour and name 2 types:
The response of an organism to its environment that increases its chance of survival. Behaviours can be learned or innate.
What is innate behaviour?
A response in an animal without learning. It is inherited and all members of a species produce the same response. It has few neurones associated and has basic survival value.
What type of tropism do plant roots exhibit to light?
Negative phototropism.
What type of tropism do plant shoots exhibit to gravity?
Negative gravitropism.
What are plant growth regulators and name an example?
They are chemical signals often called plant hormones. An example of a PGR is Indole Acetic Acid.
What does IAA do to the roots and shoots?
For the roots it inhibits growth, whilst for the shoots it stimulates growth.
How does IAA react to gravity?
It falls down and follows gravity.
How does IAA react to light?
It moves to the shaded side.
