Co-ordination and Control: Stimulus Response Flashcards
What is a stimulus?
a change in surroundings that an organism can detect
What is a receptor?
a specialised cell which detects stimuli
How do receptors respond?
they change their energy into electrical impulses
What are the five types of sense organs?
- eyes
- ears
- nose
- tongue
- skin
What receptors are found in the eyes?
light receptors
What is the structure of a retina cell?
- similar to animal cell
- has nucleus, cytoplasm and cell membrane
What receptors are found in the ears?
- sound receptors
- balance receptors
What are balance receptors sensitive to?
changes in position
enable us to keep or balance
What receptors are found in the nose?
chemoreceptors (smell receptors)
What receptors are found in the tongue?
taste receptors
What are taste receptors sensitive to?
- chemicals
- types of tastes: bitter/ sweet/ savoury
What receptors are found in the skin?
skin receptors
What are skin receptors sensitive to?
- touch
- pressure
- pain
- temperature
five stages of stimulus response
- stimulus
- receptors
- co-ordinator
- effector
- response
What is the coordinator?
- CNS: where incoming information is processed
- brain / spinal cord
What is the effector?
muscles / gland
How do muscles respond?
contract
How do glands respond?
secrete hormones
what is a reflex arc?
an automatic response to a stimulus for protection against damage in shortest input output response involving three neurones
What is a neuron?
a single nerve cell
What are the three types of neurones?
- sensory
- relay
- motor
What is a synapse?
- region where one nerve ends and another one starts
- releases a chemical to transfer info via diffusion
Features of motor neurones
- branches
- elongated section
- surrounds
How do branches help the neuron?
allows inputs from different points
pick up more than one piece of info at a time
How does the elongated section help the neuron?
- transfers info to different parts of body
up to 1 metre long
How do surrounds help the neuron?
layer of insulation for electrical impulses to prevent them from changing neurones
