Biopsychology: Neurons and synaptic transmission Flashcards
What is a neuron?
The basic building blocks of the nervous system, neurons are nerve cells that process and transmit messages through electrical and chemical signals.
What are the three types of neuron?
Motor
Sensory
Relay
What are sensory neurons?
These carry messages from the PNS to the CNS. They have long dendrites and short axons.
What are relay neurons?
These connect the sensory neurons to the motor or other relay neurons. They have short dendrites ad short axons
What are motor neurons?
These connect the CNS to effectors such a muscles and glands. They have short dendrites and long axons.
What are the 6 components of the basic structure of a neuron?
Cell body Dendrites Axon Myelin sheath Nodes of Ranvier Terminal Buttons
What is the cell body?
It includes a nucleus, which contains genetic material of the cell.
What are dendrites?
Dendrites are branch-like structures that carry nerve impulses from neighbouring neurons towards the cell body.
What is the axon?
Carries the impulses away from the cell body down the length of the neuron.
What is a myelin sheath?
It is an insulating layer that forms around the axon. This allows nerve impulses to transmit more rapidly along the axon. If the myelin sheath is damaged, impulses slow down.
What are Nodes of Ranvier?
It segments the myelin sheath. They speed up transmission of the impulse by forcing it to jump across the gaps along the axon.
What are terminal buttons?
They’re at the end of the axon and communicate with the next neuron in the chain across the synapse.
What is synaptic transmission?
The process by which neighbouring neurons communicate with each other by sending chemical messages across the synaptic cleft that separates them.
What is a neurotransmitter?
Brain chemical released from the synaptic vesicles that relay signals across the synapse from one neuron to another. Neurotransmitter can be broadly divided into those that perform an excitatory function and those that perform an inhibitory function.
What is excitation?
When a neurotransmitter, such as adrenaline, increases the position charge of the postsynaptic neuron. This increases the likelihood that the neuron will fire and pass on the electrical impulse.
