NERVOUS SYSTEM

• Nervous System - controls and coordinates the activities of all your body parts
• The Central Nervous System (CNS) - receives information from the sense organs, interprets this information, and generates responses
• CNS consists of the brain and the spinal cord
• The Peripheral Nervous System (PNS)

  1. Connects the CNS to the other parts of the body
  2. Consists of 2 different types of nerves: Cranial Nerves and Spinal nerves
• 1. Cranial Nerves - nerves that are directly connected to our brain
  2. Spinal Nerves - nerves that are connected to the spinal cord
• The 2 Divisions of PNS:

  1. Somatic Nervous System - responsible for actions that we can control
  2. Autonomic Nervous System - responsible for the involuntary functions of our body
• Brain - the control center of our body, responsible for our learning, thinking, remembering, interpreting stimulus and how to respond to it
• Brain - a 3-pound organ that consists of 10 billion neurons, and is protected by the skull
• Brain's 3 main parts:

  1. Cerebrum
  2. Cerebellum
  3. Brain stem
• Brain's 3 main parts:

  Cerebrum - the large upper region of the brain, divided into 4 lobes: frontal, temporal, parietal, and occital lobes

  2 hemispheres - right hemispheres are connected by a bundle of tissue calles corpus callosum
• Brain's 3 main parts

  Cerebellum - the little brain located beneath the back portion of the cerebrum
• Brain's 3 main parts

  Brain stem - also known as the lower brain, responsible for involuntary functions such as heartbeat, breathing, and digestion
• Neuron or nerve cell - the basic functional unit of the nervous system
• Nerve - a specialized cell which consists of a cell body and several nerve fibers: dendrites and axon
• Dendrites - carry impulses towards the cell body

  Axon - carries impulses away from the cell body
• 3 types of neuron:

  1. Sensory neuron
  2. Interneuron
  3. Motor neuron
• The nervous system is made up of hundreds of billions of neurons
• A group of neurons working together is called nerve.
• Nerves are classified according to their function
• 1. Autonomic nerves - nerves that control the involuntary functions of the body
• 2. Motor nerves - control our voluntary functions
• 3. Sensory nerves - nerves that receive stimulus or information from our sense organ