Biopsychology- structure + function of sensory relay and motor neurones Flashcards
What do neurones do?
Receive info + transmit it to other cells
What are neurones?
cells in nervous system that carry nerve impulses around the body to control behaviour
How many neurones are in the brain?
100 billion
How many neurones are in the spinal cord?
1 billion
What are neurones an essential part of ?
Massive communication systems within the body
What are the 3 types of neurones?
Sensory
Relay
Motor
What is the function of the sensory neurones?
Tell the rest of the brain about external + internal environment by processing info taken from one of the five senses
What is the function of the relay neuron?
Carrying messages from one part of the CNA to another. They connect motor + sensory neurones
What is the function of the motor neurone?
Carrying signals form the CNS which helps both organs, including gland + muscle function.
How do you identify a motor neurone?
cells body is at the end
What are the anatomical differences between the different neurones?
SENSORY -> unipolar as it only transmits messages
MOTOR + RELAY -> multipolar as they send + receive messages from many sources
What is the process of synaptic transmission for?
Transmitting messages from one neurone to another
What is the gap between neurones called?
Synapse
What is the name for chemical in the brain?
Neuroransmitters
Explain synaptic transmission
Where messages are transmitted from one neurone to another
Electrical nerve impulses travels down the neurone + prompts the release of neurotransmitters (chemicals in the brain) at the pre-synaptic terminal. Chemicals are then released into the synaptic fluid in the synapse. Post synaptic neurone must then quickly take up the neurotransmitters from the fluid and convert them to an electrical impulse to travel down the neurone to the next pre-synaptic terminal. Impulse continues to be transmitted.
How fast does synaptic transmission occur?
at very high speed
What does the prompt activation of messages depend upon?
Action potential of the post-synaptic neutron + the message type received.
What is the action potential?
Where precisely along the axon the message is
What can flooding ions cause?
‘potential’ in the dendrites
What are the two types neurotransmitters than can ‘unlock’ a certain message channel?
Excitatory
inhibitory
What are excitatory potentials?
STIMULATE ACTIVITY IN THE BRAIN
make it more likely for neurone to fire + so if a synapse is more likely to cause theist-synaptic neurone to fire
What do inhibitory potentials do?
CALM BRAIN + NERVOUS SYSTEM DOWN
makes it less likely to fire + the message is likely to be stopped at the post-synaptic neuron
