Nervous System Flashcards
Why do we need a nervous system
It enables humans to react to their external surroundings and coordinate behaviour in response
What are the changes in tour internal and external surroundings known as
Stimuli
What are the cells that detects stimuli known as
Receptors
What is the travelling of impulses called
Neurotransmission
How is information carried around the nervous system
Electrical signals (impulses) and nerve cells
How fast does the nervous system transmit information
1 to 120 metres per second
What is the central nervous system made up of
Brain and spinal cord
What is the myelin sheath
A fatty layer around the dendron and the axon
Name 2 ways the myelin sheath supports neurotransmission
- Electrically insulates the neurone from neighbouring neurones in a nerve
- Stops the signal loosing energy and increases the speed of neurotransmission
Why do we need reflexes
So your body can respond quickly
What are the purpose of reflexes
Avoid danger or harm and protect your body, breathing and moving food through digestive system
What is a path of a neural response different to the path of a reflex response
Neural response has a central nervous system but the reflex response doesn’t as it needs to move as quick-as possible
What are the 3 neurones involved in a reflex action
- Sensory beurone
- Motor neurone
- Relay neuron
What are the 3 steps involved in neurotransmission at the synapase
- Electrical impulse arrives a synapses causing the release of neurotransmitters
- The neurotransmitters diffuse across the synopses
- The neurotransmitters binds to receptors on the next neurone and triggers an electrical impulse
