1. Anatomy & Physiology Nervous System

2. 2 main sections – Central Nervous System (CNS) – Peripheral Nervous System (PNS)

3. Central Nervous System Brain = mass of nerve tissue Weigh about 3 lbs. Reaches full size @ about 6yrs. Old 3 – 5 min. supply of oxygen for nerve cells Blood brain barrier = blood flowing is filtered; harmful chemicals cannot enter the brain

4. Spinal Cord Connected from medulla oblongata to lower back (lumbar) Vertebrae surround & protect spinal cord Responsible for carrying info to the brain & to body cells

5. Meninges 3 layer covering of the brain & spinal cord (protects) Dura matter – Tough outer membrane Arachnoid membrane – Web like middle layer Pia mater – Inner layer; attached to brain Cerebrospinal fluid (CSF) = clear, watery liquid surrounding brain & spinal cord (cushions)

6. Sections of the Brain Cerebrum – Largest section – Separated into lobes – Responsible for reasoning, thoughts, emotions, memory, speech, senses, movement – Corpus Callosum (larger bundle of nerve fibers) Attaches L & R hemispheres

7. Cerebellum – Located below the back of the cerebrum – Responsible for muscle coordination, balance, posture, muscle tone

8. Diencephalon – Thalamus Directs sensory impulses – Pituitary gland Secretes hormones – Hypothalamus Regulates temp. appetite, water balance, sleep, & blood vessels

9. Brainstem Midbrain – Responsible for conducting eye & auditory reflexes Pons – Responsible for certain reflexes (chewing, saliva) – Assist with respirations Medulla oblongata – Connects with spinal cord – Responsible for regulating heartbeat, respirations, swallowing, coughing, & blood pressure

10. Peripheral Nervous System 2 types of systems – Somatic – Autonomic Somatic – 12 pairs of cranial nerves (along with spinal nerves) – Responsible for special senses

11. Autonomic – Maintains a balance of involuntary functions – Sympathetic / Parasympathetic maintains balance (homeostasis) Sympathetic – prepares the body for an emergency (increases heart rate, blood pressure) Parasympathetic – after an emergency (slows the body actions)