Neurons Flashcards
What are neurons?
Cells that are specialised to carry neural information throughout the body.
What is the structure of a neuron?
Neurons consist of…
1: a cell body
2: dandrites
3: an axon
What is the function of the dandrite at the end of a neuron?
They receive signals from other neurons or sensory receptors, and are connected to the cell body.
What is the function of the cell body?
The cell body is the control centre of a neuron - it sends impulses to from the dandrites to the axon.
What is the main function of the axon?
To carry impulses from the cell body
What is a sensory neuron?
Carries nerve impulses from the sensory receptors (eyes, ears, skin, etc) to the spinal cord and brain (the CNS)
Why does some sensory information fail to reach the brain?
Some neurons terminate in the spinal cord to allow simple reflexes to occur quickly without involving the brain (e.g pulling hand away from fire)
What is a relay neuron?
The most common type of neuron in the CNS. They allow sensory and motor neurons to communicate with each other
What does a motor neuron do?
forms synapses with muscles to control their contractions.
it releases neurotransmitters that bind to receptors on the muscle to trigger a response = muscle movement.
What is a neurotransmitter?
A chemical substance that transmits nerve impulses across a synapse (a junction between two nerve cells)
What are the 3 types of neurons?
1: sensory neurons
2: relay neurons
3: motor neurons
