Structure & Function of the Neuron Flashcards
What does the nervous system consist of?
Neurons (nerve cells) & glia (glial cells).
What do glial cells do?
They carry out repairs, act as insulators, and remove waste products from the brain.
What is the role of glial cells in relation to neurons?
Glia surrounds neurons, protects them, supplies them with nutrients, and removes dead neurons.
At first, it wasn’t thought that…
… glial cells have a role in transmitting messages.
How do glial cells in the hippocampus have a role in transmission?
Because they have a role in releasing gliotransmitters, which have a role in synaptic transmission.
They also have a role in clearing neurotransmitters away in the synaptic gap.
What are gliotransmitters?
Chemicals released from glial cells that facilitate neuronal communication between neurons and other glial cells.
What forms the myelin sheath of myelinated neurons?
Glial cells, which wrap around the nerve fibres to form it.
What are the 3 types of neurons?
1 - motor neurons
2 - sensory neurons
3 - inter-neurons
What are motor neurons?
Neurons that receive messages from the CNS to generate movements.
What are sensory neurons?
Neurons that transmit messages about senses, such as sight & sound, from the sense organ to the brain and spinal column.
What are inter-neurons?
Neurons that take messages from neuron to neuron
What are dendrites?
Finger-like structures that surround a cell body & form a tree-like structure.
They receive synaptic impulses from axons.
What is an axon?
A thin fiber that extends from a neuron.
Electrical impulses from the neuron travel away from the axon to be received by other neurons.
Where does an axon end?
At an axon terminal.
The axon is where…
… the electrical signal from the cell body travels.
An axon terminal has more than one…
… telodendron (terminating branch).
What is at the end of each telodendron?
A terminal button.
What is the axon protected by?
The myelin sheath.
Which type of glial cells make up the myelin sheath of neurons in the peripheral nervous system?
Schwann cells.