By Kanikkinee Smith

* Vertebrates, animals with backbones and spinal columns, have central and peripheral nervous systems. * The central nervous system is made up of the brain, spinal cord and retina. * The peripheral nervous system consists of sensory neurons, ganglia (clusters of neurons) and nerves that connect to one another and to the central nervous system.

* The nervous system is a set of nerves cells that work together to receive impulses to get the body to respond to something. * Function:  is to send signals from one cell to others, or from one part of the body to others.

* Neurons are nerve cells that are able to respond to stimuli, conduct impulses and communicate with each other. * The neurons have fibers branching out like a tree on one side of the neuron called dendrites * The dendrites conduct impulses toward the cell. * On the other end of the neuron is a long fiber that is called the Axon which carry impulses away * The Myelin is a dielectric (electrically insulating) material that forms a layer, the myelin sheath that wraps around the Axon

* When the impulse travels through parts of the neuron it goes from dendrite to the cell body to the axon to the synapse

connects with the spinal cord. * Medulla Oblongata is part of the brain that connects with the spinal cord. keep your balance, and move around * Cerebellum-It controls balance, movement, and coordination (how your muscles work together). Because of your cerebellum, you can stand upright, keep your balance, and move around. * Cerebrum-The biggest part of the brain. The cerebrum makes up 85% of the brain's weight, and it's easy to see why. The cerebrum is the thinking part of the brain and it controls your voluntary muscles - the ones that move when you want them to.

* The cerebrum is divided into left and right cerebral hemispheres Parietal lobe Frontal lobe Temporal lobe Occipital lobe

meninges dura mater * The CNS is enclosed and protected by meninges, a three-layered system of membranes, including a tough, leathery outer layer called the dura mater which lies between the skull and arachnoid. ventricles * The ventricles are filled with cerebrospinal fluid (CSF) which bathes and cushions the brain and spinal cord within their bony confines.

* The autonomic nervous system (ANS) (visceral nervous system or involuntary nervous system) is the part of the peripheral nervous system that acts as a control system. Functioning largely below the level of consciousness, and controls visceral functions. The ANS affects heart rate, digestion, respiratory rate, salivation, perspiration, pupillary dilation, micturition (urination), and sexual arousal.

* The nervous system can also experience functional difficulties, which result in conditions such as epilepsy, Parkinson's disease, multiple sclerosis, amyotrophic lateral sclerosis (ALS), Huntington's chorea, and Alzheimer's disease. * Infections such as meningitis, encephalitis, polio, and epidural abscess can also affect the nervous system. * Structural disorders such as brain or spinal cord injury, Bell's palsy, cervical spondylosis, carpal tunnel syndrome, brain or spinal cord tumors, peripheral neuropathy, and Guillain-Barré syndrome also strike the nervous system.

* Epilepsy - is a brain disorder in which a person has repeated seizures (convulsions) over time. The doctor will perform a physical exam, which will include a detailed look at the brain and nervous system. An EEG (electroencephalogram) will be done to check the electrical activity in the brain * Multiple sclerosis -Multiple sclerosis (or MS) is a chronic, often disabling disease that attacks the central nervous system (CNS), which is made up of the brain, spinal cord, and optic nerves. Symptoms may be mild, such as numbness in the limbs, or severe, such as paralysis or loss of vision. The progress, severity, and specific symptoms of MS are unpredictable and vary from one person to another. Today, new treatments and advances in research are giving new hope to people affected by the disease Relapsing-Remitting MS * People with this type of MS experience clearly defined attacks of worsening neurologic function. These attacks—which are called relapses, flare-ups, or exacerbations —are followed by partial or complete recovery periods (remissions), during which no disease progression occurs. Approximately 85% of people are initially diagnosed with relapsing- remitting MS.

* Amyotrophic lateral sclerosis- is a debilitating disease with varied etiology characterized by rapidly progressive weakness, muscle atrophy and fasciculations (twitching), muscle spasticity, difficulty speaking, difficulty swallowing, and difficulty breathing. * Meningitis-is inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. Can be cured with antibiotics! * Carpal tunnel syndrome- is a condition in which there is excessive pressure on the median nerve. This is the nerve in the wrist that allows feeling and movement to parts of the hand. Carpal tunnel syndrome can lead to numbness, tingling, weakness, or muscle damage in the hand and fingers.

* Bell’s palsy- A form of Neuritis that involves paralysis of the facial nerve causing weakness of the muscles of one side of the face and an inability to close the eye. * Cerebral palsy- A non-progressive disorder of movement resulting from damage to the brain before, during, or immediately after birth. * Sciatica- A common condition arising from compression of, or damage to, a nerve or nerve root. * Parkinson’s disease-degenerative disease process(associated with aging) that affects the basal ganglia of the brain. * Shingles- is a painful skin rash. Common in older adults and is involved with the integumentary(deals with skin, hair and nails) System

By Breanna Davis

The orbits, eye lashes, and lacrimal glands all serve as protection for the eye. When you cry the fluid that comes through your nose is actually tears The retina is inside the eye so you cannot see it. The two functions of the eye a refract and accommodate light. The mucus membrane also known as conjuctivia the conjunctiva is the thin, transparent tissue that covers the outer surface of the eye. If you look at a picture light rays pass through the retina

Cont. Eye conditions A person with a normally shaped eye ball can get a condition called presbyopia which is farsightedness caused by loss of elasticity of the lens of the eye, occurring typically in middle and old age. Glaucoma- is the slow loss of ones vision, which is usually treated by medication Strabismus- is a disorder in which the two eyes do not line up in the same direction, and therefore do not look at the same object at the same time. The condition is more commonly known as "crossed eyes.“ Myopia- or nearsightedness can be corrected by radialkeratomomy

The Ear

The largest structure of the ear is called the pinna. Ear wax also known as cerumen is found in the External Auditory canal. Ossicles are the three tiniest bones in the body form the coupling between the vibration of the eardrum and the forces exerted on the oval window of the inner ear if removed you would not be able to transmit sound waves into your inner ear. When sound is heard the first to transmit sound would be the tympanic membrane The only organ of the inner ear that is no involved in hearing is the semicircular canals.

The nose

Olfactory receptor neurons are responsible for the detection of odor molecules. Activated olfactory receptors are the initial player in a signal transduction cascade which ultimately produces a nerve impulse which is transmitted to the brain.(found in the nose.)