Flashcards in Sensory Reception Deck (17):
What is a stimulus?
A detectable change in the internal or external environment of an organism that produces a response in the organism
What is the main advantage of being able to respond to stimuli?
It increases an organisms chances of survival
What causes organisms with more appropriate responses to be favoured?
What detects stimuli?
Cells or organs known as receptors
What do receptors do?
They transform the energy of a stimulus into some form of energy that can be processed by the organism and leads to a response
What carries out the response to a stimuli?
What is one way in which receptors and effectors can communicate?
Via chemicals such as hormones
How do the receptors and effectors in animals communicate so rapidly?
The communicate via the nervous system
What is each effector and receptor linked to?
A central coordinator
What is a taxis?
A simple response whose direction is determined by the direction of the stimulus
What sort of organisms respond directly to environmental changes by moving its whole body either towards a favourable stimulus or away from an unfavourable one?
A motile organism
Taxes are classified in two ways. What are they?
Positive and negative taxis
Name 2 types of taxis
Phototaxis and chemotaxis
What is a kinesis?
A form of response in which the random movements of an organism increases in response to unpleasant stimuli
What is a kinesis response designed to do?
To bring the organism back into favourable conditions
What is a tropism?
A growth movement of part of a plant in response to a directional stimulus