Neurons Flashcards
What are neurons?
- Carry information throughout the body
What are dendrites and their function?
At each end of neuron receive signals from other neurons
- Connected to cell body
What is the axon covered in?
Myelin sheath
- Allows nerve impulses to travel more rapidly
Structure and process of neuron
- Dendrite receieves signal
- Carried towards cell body
- Travels along axon
- Reaches end and sends electrical signal to next neuron
What is a sensory neuron?
Carry nerve impulses from sensory receptors (receptors for vision/taste etc) to spinal cord and brain
What is a relay neurone?
Allows sensory and motor neurons to communicate with each other
- Only found in brain and spinal cord
What is a motor neurone?
Carry nerve impulses to muscles which triggers muscle contraction
What are neurons separated by and what is synaptic transmission?
Synapses and synaptic transmission is the process of sending info from one neuron to another
What do synaptic vesicles contain?
Chemical messengers that assist in the transfer of the impulse, neurotransmitters
Process of synaptic transmission
- Action potential triggers the synaptic vesicles containing neurotransmitters to migrate towards the pre-synaptic membrane
- Vesicle fuses and releases neurotransmitters and they diffuse across the gap
- They then bind to specialised receptors in the membrane of the post-synaptic cell
- They are then activated and produce either excitatory or inhibitory effects on postsynaptic neuron
What are excitatory neurotransmitters?
Examples
Increases the likelihood of the neuron firing
- Noradrenaline
- Results in EPSP
What is an inhibitory neurotransmitter?
Examples
Decrease the likelihood of the neuron firing
- Serotonin
Generally responsible for calming the mind and filtering out unnecessary exictatory signals
- Results in IPSP
What determines whether the neuron will fire?
Summation of EPSP and IPSP
