The Nervous System Flashcards
What is the point of the nervous system
To detect and react to stimuli. Humans need to do this in their environment in order to survive
What are the different parts of the nervous system
- The Central Nervous System: the brain and spinal cords, connected to sensory and motor neurones
- The sensory Neurones: carry information as electrical impulses from the receptors to the CNS
- Motor neurones: Carry electrical impulses from the CNS to effectors
- Effectors: all your muscles and glands which respond to nervous impulses
What are receptors
- cells that detect stimuli
- You can have taste receptors on tongue or sound receptors in ear
- Receptors can form part of larger, complex organs
What are effectors
- they respond to nervous impulses and bring about a change
- muscles and glands are effectors because muscles contract and glands secrete in response to a nervous impulse
Describe how the CNS works
Stimulus—>Receptor—>Sensory neurone—>CNS—>Motor neurone—>Effector—>response
What is a synapse
The connection between 2 neurones
How are signals emitted across a synapse
Triggers chemicals that diffuse across the synapses, in order to set off a new electrical signal in the next neurone
What are reflexes
Reflexes are rapid, automatic responses to certain stimuli that don’t involve the conscious part of the brain. They can help reduce the chances of being injured. For an example when a ball is thrown, you have a natural reflex to catch it so that you don’t get hurt
What is a reflex arc
The passage of information in a reflex (from receptor to effector)
How does the reflex arc go through the CNS
Stimulus->Receptor->sensory neurone->relay neurone->motor neurone->effector
- It goes through the spinal cord or unconscious part of the brain
- response is quicker than normal response because you don’t have to think about it
