1. The Nervous System Dont get nervous about the nervous system

2. Functions of the Nervous System 1. Communication and coordination –Adapt and respond to changes from both inside and outside the body 2. Site of reasoning- your brain 3. Two main divisions –Central nervous system (CNS): brain and spinal cord –Peripheral nervous system- the nerves

3. Neuron- basic structural unit of the nervous system Dendrites- carry impulses towards the cell Axon-carry impulses away from the cell Myelin sheath Synaptic terminal –Epinephrine –Norepinephrine –Acetylcholine

4. Nerves are made of many nerve cells Afferent-sensory nerves carry message to brain Efferent-motor neurons carry message from brain to muscle Associate- do both Heads up

6. Central nervous system Brain and spinal cord

7. Cerebrum-largest part of brain. Responsible for reasoning, thought, memory, speech, sensation, etc. Divided into two halves. Further divided into lobes; occipital, parietal, temporal and frontal

8. Cerebellum- responsible for muscle coordination Brain stem- most basic functions; respiration, swallowing, blood pressure. Lower part (medulla oblongata) is continuous with spinal cord

9. Spinal cord- begins at foramen magnum and ends at second lumbar vertebrae Contains both afferent (to the brain) and efferent (motor neurons- away from the brain)

10. Both the brain and spinal cord are covered by a membrane system called the meninges In addition, the brain has four hollow areas called ventricles. Cerebrospinal fluid is produced in the ventricles and baths the brain and spinal column

11. Peripheral nervous system Somatic system –12 pairs cranial nerves –31 pairs spinal nerves Autonomic –Sympathetic Fight or flight –Parasympathetic

12. Disorders of the nervous system Meningitis- inflammation of the linings of the brain and spinal cord Encephalitis- inflammation of the brain Epilepsy-seizure disorder. Excessive discharge from neurons. 1 in 200 suffer. Grand mal or petit mal seizures Cerebral palsy- disturbance in voluntary muscular action Parkinsons –decreased neurotransmitter MS multiple sclerosis- autoimmune