Transcript Nervous System

Regulation
• The process by which an organism
controls and coordinates its activities
• Done by:
– Nervous system
– Endocrine system
Nervous system
• Use cells called neurons to send impulses
– Impulses are electrical messages
• The nervous system is really fast but its
effects don’t last long
A neuron
Nerves
• Consist of bundles of neurons
Reflex arc
Reflex arc
• A stimulus is picked up by a receptor
• The receptor sends an impulse to the sensory
neuron
• The sensory neuron brings impulse to
interneuron
• The interneuron is found in the brain and spinal
cord
– It sends impulse to motor neuron
• The motor neuron brings impulse to effector
• The effector carries out a response
– A muscle contracts
– A gland secretes a hormone