Science q3-w2

• Central Nervous System - serves as the main processing center for the entire nervous system. It consists of two main components, namely the:

  1. Brain
  2. Spinal Cord
• Brain - This is an organ located within the skull that functions as organizer and distributor of information for the body. It has three main parts

  1. Cerebrum
  2. Cerebellum
  3. Brain Stem
• Cerebrum –  large, upper part of the brain that controls activity and thought.
• Cerebellum – the part under the cerebrum that controls posture, balance, and coordination.
• Brain Stem – the part that connects the brain to the spinal cord and controls automatic functions such as breathing, digestion, heart rate, and blood pressure.
• Spinal Cord - This serves as a channel for signals between the brain and the rest of the body, and controls simple musculoskeletal reflexes without input from the brain.
• Peripheral Nervous System - The PNS connects the central nervous system to the organs and limbs. It has two main divisions:

  1. Somatic Nervous System
  2. Autonomic Nervous System
• Somatic Nervous System - This system is associated with the voluntary control of body movements and has two main parts:

  1. Spinal Nerves
  2. Cranial Nerves
• Autonomic Nervous System - This system is associated with the involuntary control of body movements and has two subdivisions:

  1. Sympathetic
  2. Parasympathetic
• Spinal Nerves - the nerves that carry motor and sensory signals between the spinal and the body.
• Cranial Nerves - the nerves fibers that carry information into and out of the brain stem
• Sympathetic - it is activated when the body is in a dynamic role of stress.
• Parasympathetic - it maintains body functions and restore the body to normal or relaxed mode.