2.84 Sensory repsonses

understand that stimulation of receptors in the sense organs sends electrical impulses along nerves into and out of the central nervous system, resulting in rapid responses

http://www.usmanscience.com/12bio/classnotes/nervous_system_notes_files/image002.gif

1. Sensory nerves: Receptors
- Sends messages along the sensory neurones to the central nervous system

2. Motor neurones: Effectors
- Receive messages from the CNS

3. Impulses
- Passed from receptor to coordinator via axon in sensory nerves
- Brain generates information
- Generates another impulse down the motor nerves to the effector

Voluntary actions - Involvement of brain
Involuntary actions - Passed through the spinal cord (less distance)

4. Structure of neurone
- Meeting of nerves - do not actually touch
- Synapses: a gap in which the electric current jumps through
- Some axons have a fatty sheath around them
- Insulates axon, makes the impulse travel faster