The Nervous System

The Nervous System

1. Definition

   • It detects and reacts to a stimuli as they reacts to their surroundings and coordinates their behaviour to survive.

2. What is the nervous system made up of?

   • Centeral Nervous System (CNS)- In vertebrates this consists of the brain and spinal cord only. In mammals the CNS is connected by sensory neurons and motor neurons.
   • Sensory Neuron- the neurons that carry information as electrical impluses from the receptors to the CNS.
   • Motor Neurons- the neurons that carry electrical impulses from the CNS to effectors
   • Effectors- all your muscles and glands, which respond to nervous impluses.

3. Receptors, Effectors and Complex Organs

   • Recptors ae the cells that detect stimuli, there are many deffierent types of receptors such as taste and sound, receptors can form part of larger complex organs, effectors respond to nervous impluses and bring about chnageand muslces and glands respond in defferent ways. Muscles contract in response to nervous impluses whereas glands secrete hormones.

4. The Central Nervous System (CNS) Coordinates the Response.

   • The CNS is a coordination center- it recieves information from the receptors and then coordinates the response. The response is then carried out by effectors.