nervous system

• Nervous System 


  A communication network that controls many bodily functions
• The nervous system is made up of cells called neurons which make up the brain, spinal cord and nerves.
• Central Nervous System (CNS)


  Consists of the brain and spinal cord
• Brain


  The control centre of the body
• Spinal Cord


  Carries messages from the brain to the body and body to the brain
• Peripheral Nervous System (PNS)


  Consists of a network of nerves where messages are sent to and from the CNS
• The PNS collects messages from sense receptors to send to the brain and takes messages from the brain/CNS to the muscles
• Cerebrum


  The largest part of the brain and consists of 3 functional areas.
• The functions the cerebrum is involved in includes thinking, learning, intelligence, reasoning and memory.
• The cerebrum is concerned with the perception of the senses, the processing of information and initiation and control of voluntary muscle contractions.
• The functional areas are sensory, motor and association areas
• Sensory Areas


  interprets impulses from receptors
• Motor areas


  Controls muscular movements
• Association areas


  concerned with intellectual, emotional processes and memory
• The cerebellum is the second largest part of the brain and is found under the rear part of the cerebrum. It looks like a cauliflower cut in half.
• Cerebellum


  Controls posture and balance, fine motor coordonation of voluntary muscles (like writing) and smooth movements. These are known as fine motor skills.
• Hypothalamus


  A small, internal, central region of the brain that regulates vital body functions like homeostasis, emotions and hormone regulation, which is done by the endocrine system.
• Medulla Oblongata


  Region of the brain that is essential for life
• The medulla oblongata regulates heart rate (Cardiac centre), breathing (Respiratory centre), swallowing, blood pressure, sneezing, coughing and vomiting.
• There are types of centres in the medulla oblongata: the cardiac centre and the respiratory centre.
• The spinal cord is made up of grey matter and white matter. Grey matter contains cell bodies and dendrites while white matter contains axons.
• The cardiac centre controls the heartbeat and rhythm. The respiratory centre controls the depth and speed of our breaths.
• Corpus Callosum


  A band of nerves connecting the two halves of the brain
• The corpus callosum transfers sensory, motor and cogniative information between the two hemispheres
• Spinal Cord


  A long nerve cord extending from the base of the skull to the 2nd lumbar vertebrae
• The spinal cord is the transport system of the CNS
• The ascending tracts of the spinal cord are nerve impulses TOWARDS the brain from the PNS
• The descending tracts conduct impulses AWAY from the brain to the PNS
• The cerebral cortex controls higher functions such as thinking, memory, language and consciousness
• The spinal cord integrates relflexes, autonomic responses and the reflex arc
• The CHS controls all aspects of life, so it is essential to protect it
• The CNS IS protected by cerebrospinal fluid (CSF), meninges, cranium and vertebrae
• Cerebrospinal fluid 


  a clear fluid which surrounds the brain and spinal cord and acts as a shock absorber
• Meninges


  3 connective tissue layers surrounding the brain and spinal fluid and work together by decreasing friction with bones
• Dura mater


  A thick layer of tough fibrous connective tissue that sticks to the bones of the skull
• Arachnoid mater


  A thin layer thats covered in CSF and allows the Dur master to connect to the pia mater
• Pia Mater


  A soft delicate layer that contains many blood vessels and sticks to the surface of the brain and spinal cord. Can also be called the subarachnoid mater.
• Cranium


  The bones of skull, which work together by encasing the brain and preventing impact
• Vertebrae


  Bones of the backbone, which work by encasing the spinal cord and preventing impact
• The PNS connects to the CNS with nerves, receptors, muscles and glands