Nervous System

• The nervous system is responsible for regulating and coordinating the

  activities of all the other systems of the body.
• It is the nervous system which enables a person to speak, listen with

  understanding, comprehend what is going on around, solve problems,

  interact intelligently, and be creative.
• Central Nervous System or CNS- It is composed of the brain and the spinal cord. It

  is responsible for issuing nerve impulses and analyzing sensory data.
• Peripheral Nervous System or PNS- Includes nerves of the sense organs. It carries all the messages sent between the central nervous system and the rest of the

  body.
• Peripheral Nervous System or PNS consists of 12 pairs of cranial nerves that originate in the brain, plus 31 pairs of spinal nerves of the spinal cord.
• Nerve cell or neuron is the basic unit of the nervous system.
• Cell body- Cell body of a neuron contains the nucleus and the most of the neuron’s

  organelles.
• Dendrites- Are the numerous, short, and highly branched extensions of the

  neurons that receive nerve impulses and conduct them toward the cell body.
• Axon- Is the long extension of the neuron. It carries a nerve impulse away from the

  cell body to another neuron or to another neuron or to a muscle or gland.
• Synaptic terminal- Is the end part of the neuron.
• Myelin sheath- Speeds up the conduction of impulses along the axon.
• The brain is the master control center of the nervous system.
• The brain is about 1.4 kg.
• The brain is responsible for issuing nerve impulses, processing nerve impulses data engaging in the higher order thought process.