B11-The Nervous System Flashcards
What are the two sections of the nervous system
1) The central nervous system
2) The peripheral nervous system
What is the central nervous system made of
Brain and spinal-cord
coordination Centre
What is the peripheral nervous system made of
Every other nerves
What are neurons
They are nerve cells
What are the three types of neurons
Sensory neuron
Relay neuron
Motor neuron
What is the pathway of a normal electrical impulse
1) Stimulus
2) Receptors
3) Stimulus converted to electrical impulse
4) Sensory neuron
5) Coordination Centre (brain)
6) Relay neuron
7) Motor neuron
8) Effectors
9) Response
What is the pathway of electrical impulse in a reflex action
1) Stimulus
2) Receptor
3) Sensory neuron
4) Coordination Centre (spinal cord)
5) relay Neuron
6) Motor neuron
7) effectors
8) Response
How does an electrical impulse across the synapse
1) The electrical impulse reaches the end of the first neuron
2) This stimulates the release of neurotransmitter chemicals
3) The neurotransmitter chemical defuses across the sunapse and bind to receptors on the receiving neuron
4) The impulse can now pass along the next neuron
What is a synapse
The synapse is a gap between 2 neurons.
What is a reflex action
It is a ‘inbuilt’ involuntary protective responses. We don’t have to think about them, they just happen! The electrical impulse travels through the spinal cord instead of (straight away) going to the brain. This pathway is called a reflex arc.
Why are reflex actions important?
They are automatic, fast, protective responses.
