Nervous System Flashcards
What is the nervous system?
It allows us to interact with the world around us and responds to change in the environment therefore meaning it’s important for homeostasis
What are the two main parts of the nervous system?
Central nervous system
Peripheral nervous system
What is part of the central nervous system?
The brain and spinal cord
What does the PNS do?
Detects changes in the external environment as well as internal
It sends signals and info to the CNS and causes it to respond
How does the nervous system work?
Incoming info is transmitted by the sensory neutron and distributed to the brain
Brain interprets information and coordinates a response
Response flows out the CNS via a motor neurone to organs, glans and muscles and make changes
What are neurones?
They are the cells of the nervous system
They are the cells that carry messages as electrical impulses allowing rapid communication
They are specialised with different forms depending on where in the nervous system they are and what function they have
What are the components of neurones?
Dendrites Cell body Axon Myelin sheath Nodes of ranvier
What do dendrites do?
Specialised to receive chemical signals from the axon terminals of other neurones to conduct it towards the cell body
What is the cell body?
Contains the contents of the cell
What is the axon?
Specialised for the conduction of action potentials away from the cell body.
What is the myelin sheath?
Fatty covering over the axon which protect and insulates the axon and helps speed up the impulse transmission
What are the nodes of ranvier?
The gaps formed between the myelin sheath along axons that allow skipping of impulses which then allows faster movement
What are nerves?
A collection of axons found in neurones
What is a synaptic sending cell?
A presynaptic neurone
What is a receiving synaptic cell called?
A postsynaptic neurone
