Simple Responses Flashcards
What are simple responses?
Rapid automatic responses protect the organisms from harmful stimuli.
What is a stimulus?
A change in the environment.
What are receptors?
They are cells or proteins in cell membrane that detect a stimulus.
What is an effector?
A muscle or gland that brings about a response.
How does the nervous system detect the stimulus and bring about a simple reflex in response to it?
- The receptors detect the stimuli and send electrical impulses along the sensory neuron
- The sensory neuron carries the electrical impulse from the receptors to the CNS.
- The relay neurone allows the electrical impulse to be transferred from the sensory neurone to the motor neurone.
- The motor neurone carries the electrical impulse from the CNS to the effector.
- The effector brings about a response.
Why is it important that organisms respond to changes in their environment?
It increases their chances of survival.
What are taxi responses?
A directional movement in response to a stimuli.
What is an example of a taxi response?
A shoot undergoing positive phototropism in response to light and the roots undergoing negative phototropism in response to light.
What is a kinesis response?
A random movement in response to stimuli.
Why are taxis and kinesis responses important?
They keep a mobile organism in a favourable environment.
