Med Term Presentation #2


Published on

The Nervous System

Published in: Health & Medicine
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide
  • Med Term Presentation #2

    1. 1. Chapter 12 Nervous System
    2. 2. Overview The nervous system is coordinates and controls body function. It receives sensory input, makes decisions, and then orders body responses. The nervous system can be subdivided into the central nervous system (CNS) and the peripheral nervous system (PNS).
    3. 3. The Central Nervous System The CNS consists of the brain and the spinal cord; it is able to receive impulses from all over the body, process this information, and then respond with an action. Sensory information comes into the central nervous system, where it is processed. Motor messages then exit the CNS carrying commands to the muscles and glands. Consist of gray and white matter gray matter: comprised of unsheathed or uncovered cell bodies and dendrites white matter: myelinated nerve fibers Encased and protected by 3 membranes known as meninges
    4. 4. Brain One of the largest organs in the body and coordinates most body activities. Center for all thought, memory, judgement, and emotion Each part of the brain is responsible for controlling different body functions, such as temperature regulation, blood pressure, and breathing
    5. 5. Brain (cont.) 4 sections: cerebrum: largest section that processes thoughts, judgement, memory problem solving, and language Subdivided into left and right cerebral hemispheres and each hemisphere has 4 lobes-- frontal, parietal, occipital, and temporal lobes cerebellum: 2nd largest portion located beneath the posterior part of the cerebrum; aids in coordinating voluntary body movements and maintaining balance and equilibrium.
    6. 6. Brain (cont.) diencephalon: located below the cerebrum and consist if the thalamus and hypothalamus thalamus: composed of gray matter and acts as center for relaying impulses from eyes, ears, and skin to the cerebrum; pain receptors hypothalamus: controls body temperature, appetite, sleep, sexual desire, and emotions; also controlling the autonomic nervous system, digestive system, release of hormones from pituitary gland. brain stem: 3 components midbrain: pathway for impulses to be conducted between brain and spinal cord pons: connects cerebellum to the rest of the brain medulla oblongata: most inferior positioned of the brain connects brain to the spinal cord; center that controls heart rate, respiration, and blood pressure
    7. 7. Spinal Cord The function of the spinal cord is to provide a pathway for impulses traveling to and from the brain. Column of nervous tissue that extends from the medulla oblongata to the brain down the 2nd lumbar vertebra within the vertebral column 33 vertebrae of the backbone form a continuous canal for the spinal cord called the spinal cavity or vertebral canal
    8. 8. Spinal Cord (cont.) Protected by cerebrospinal fluid Inner core of spinal cord consists of cell bodies and dendrites of peripheral nerves and is gray matter Out portion of spinal cord is myelinated white matter ascending tracts: carrying sensory information to brain descending tracts: carrying motor commands down from the brain to the peripheral nerve
    9. 9. Peripheral Nervous Sytem The PNS includes both 12 cranial nerves and 31 pairs of spinal nerves Cranial nerves arise from the brain, mainly the medulla oblongata Spinal nerves split off from the spinal cord, and 1 pair (right and left) exit between each pair of vertebrae The nerves of the PNS are subdivided into 2 divisions autonomic nervous system (ANS): Involved with the control of involuntary or unconscious bodily functions 2 branches- sympathetic and parasympathetic branches somatic nerves: The skin and skeletal muscles are mainly involved with the conscious and voluntary activities of the body. These nerves carry motor commands to skeletal muscles