B17a Nervous system Flashcards
What is the function of the nervous system?
Enables humans to react to their surroundings
Coordinate behaviour
Name the organs found in the central nervous system
Brain
and
Spinal cord
Define the term stimulus
A change in the environment that is detected by a receptor
Name the organ that contains receptors that detect gases in the air
Nose
Name the organ that contains receptor detecting light
Eye
Name the organ that contains receptors that detect pain
Skin
Name the neurone that carries an electrical impulse from the receptor to the central nervous system
Sensory neurone
Name the type of cell shown in the picture
Motor neurone
What is the function of the CNS?
Central nervous system
Coordiantes the response to a stimulus
What passes along the neurones in the nervous system?
Electrical impulses
Give the sequence of events tin the nervous system
Stimulus -> Receptor -> Coordinator -> Effector -> Response
How does a stimulus lead to a response being carried out by the body?
Stimulus is converted into an electrical impulse by the receptor
Electrical impulse passes along sensory neurone to central nervous system
The CNS coordinates a response
Electrical impulse passes along a motor neurone to an effector
Effector carries out a response
What is the fucntion of the sensory neurone?
Carries electtrical impulses from the stimulus to the spainl cord
Give the fucntion of a motor neurone
Carries electrical impusles from the central nervous system to the coordinator
The diagram shows the central nervous system
Name organ A and B
A = brain
B = Spinal cord
What is a reflex action?
Automatic and rapid response
which does not involve conscious input from the brain
Why are reflex action s important?
Aid survival by preventing damage to the body
Name two effectors
Muscles and glands
What is the function of the motor neurone
Carries an electrical impulse from the central nervous system to the effector
Name the gap between 2 neurones
Synapse
Name the type of neurone found in the coordinator
Relay neurone
How does the electrical impulse cross the synapse/
A chemical is released from the first neurone.
The chemical diffuses across the synapse
An electrical impulse starts in the next neurone
Name the organ that detects sound waves
Ear
Name the three neurones found in the nervous system
Senosry neurone
Relay neurone
Motor neurone
Describe the sequence of events that happens in this refex arc
Hand touches hot pan
Heat receptors in skin detect the heat
Electrical impulses sent along sensory neurone to spinal cord
Electrical impulse send along relay neurone
Electrical imulse send along motor neurone
Muscle contracts and moves hand away from hot pan
Brain is informed that the hand has moved
The diagram show a reflex arc
Name the structure labelled D
Muscle
The diagram show a reflex arc
Name the neurone labelled C
Motor neurone
The diagram show a reflex arc
Name the neurone labelled A
Sensory neurone
