Neurons and synaptic transmission Flashcards
What are motor neurons?
Form synapses with muscles and control their contractions.
What is a neurotransmitter?
Chemical substances that play an important part in the workings of the nervous system, by transmitting nerve impulses across a synapse.
What are relay neurons?
These neurons are the most common type of neuronal in the CNS. They allow sensory and motor neurons to communicate with each other.
What is a sensory neuron?
Carry nerve impulses from sensory receptors to the spinal cord and the brain.
What is a synapse?
The conjunction of the end of the axon of one neutron and the dendrite or cell body of another.
What is synaptic transmission?
Refers to the process by which a nerve impulse passes across the synaptic cleft from one neutron to another.
Describe the structure and function or neurons.
Neurons receive a signal via their dendrites from other neurons or from sensory receptors, and pass it on via their axon. The axon is covered in an insulating layer called the myelin sheath, which allows nerve impulses to travel along it more rapidly.
Neurotransmitters are removed from the synaptic gap by
Reuptake into the presynaptic neuron, for recycling. Breakdown by enzymes.
What are excitatory neurons?
Cause an excitatory post-synaptic potential, making the postsynaptic neuron more likely to fire. Include acetylcholine and noradrenaline.
What are inhibitory neurons?
Cause an inhibitory postsynaptic potential making the postsynaptic neuron less likely to fire. Include serotonin and GABA.
