NERVOUS SYSTEM

• collection of organs that control coordinates Functions throughout the body and respond to internal & external stimuli.
• neuron are the cells that transmit these impulses, the basic units of the nervous system
• Sensory carry impulses from sense organs to the

  spinal cord and brain
• Motor carry impulses From the brain & Spinal cord to muscles and glands
• interneurons: connect sensory carry impulses between them
• Cell body (soma)

  the largest part contains nucleus & most of the cytoplasm most metabolic activities occur here

  contains
• Dendrites

  short branched extensions.

  Carry impulses From the environment or other neuron toward the body
• nucleus

  -contains genetic material (chromosomes)including info. For cell development and synthesis of proteins necessary for cell maintenance survival
• myelin sheath

  insulating membrane surrounding the axon
• axon

  1ong Fiber which carries impulses away from cell body neurons only have one axon
• Schwann cells

  keeping the neuron alive covered with myelin sheath - For development, maintenance, Function, peripheral nerves
• Nerve ending

  send messages to your brain when you feel sensations such as heat, cold, and pain.

  To release neurotransmitters when stimulated by an electrical signal carried by the axon
• synapse

  space between neurons location where a neuron can transfer an impulse to another
• neurotransmitters are chemicals used by neurons to transmit an impulse across the synapse human nervous system
• CENTRAL NERVOUS SYSTEM (CNS)

  relays messages, processes analyzes info
• PERIPHERAL NERVOUS SYSTEM

  receives information from the environment relays commands from the CNS to organs grands
• BRAIN

  made of 50-100 billion neurons
• Frontal

  memory, judgement, inhibitions, personality

  
  

  temporal long-term memory, auditory processing
• Occipital

  vision processing
• parietal

  sensory integration
• SPINAL CORD

  main communications link between the brain the rest of the body
• peripheral nervous system

  lies outside of the CNS

  consists of all the nerve cells that are not a part of the brain/spinal cord

  divided into 2 divisions sensory and motor
• sensory

  transmits impulses From sense organs to the CNS

  motor

  transmits impulses From CNS to muscles
• Somatic

  regulates conscious controlled acts.

  autonomic

  regulates activities that are automatic

  involuntary

  sympathetic - increasing

  Parasympathetic - slowing