Transcript The Nervous System

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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.
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* 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.
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* 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
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When the impulse travels
through parts of the neuron it
goes from dendrite to the cell
body to the axon to the synapse
* Medulla Oblongata is part of the brain that
connects with the spinal cord.
* 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.
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* The cerebrum is divided into left and right
cerebral hemispheres
Parietal lobe
Occipital lobe
Frontal lobe
Temporal lobe
* 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.
* The ventricles are filled with cerebrospinal
fluid (CSF) which bathes and cushions the brain
and spinal cord within their bony confines.
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* 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.
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* 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.
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*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 relapsingremitting MS.
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* 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.
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* 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
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By Breanna Davis
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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
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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.)