Transcript How messages travel through the body?

A system that controls all the
activities of the body.
The nervous system is made of:
The brain
The nerves
The spinal cord
The nervous system also allows you to
react to a stimulus.
A stimulus is a change in the environment
that causes reactions.
Example: A hot stove
Or… tripping over a rock
Messages carried throughout the body
by nerves.
Your reactions are automatic.
Automatic means that you do not
have to think about your reactions.
Example: If a bug flies by your eye,
you will blink.
You have a nerve along your whole arm.
The “funny bone” is the only place on
the arm where the nerve is not
protected.
The “funny bone” is on the elbow.
The Central Nervous System is made
of the brain and the spinal cord.
The Central Nervous System controls
everything in the body.
The Peripheral Nervous System is made
of the nerves and the sense organs.
Nerves
Sense organs
* The Central Nervous System controls
all the body’s activities.
* The Central Nervous System is
made of two main organs.
1. The brain
2. The spinal cord
• It is a cylinder of nerve tissues (a
finger thick & 45 cm long).
•It connects the brain to the sense
organs and the different parts of the
body.
•The spinal cord relays messages to
and from the brain.
• It controls some important body
actions that don’t involve the brain
(reflexes).
(SPINAL COLUMN)
*The
The
vertebrae
are
the many
vertebrae
are
the
bone
The
vertebrae
are the many
many
bones
that protect
bones
that protect
the nerves in
the nerves
in the spinal
the
spinal cord. The vertebrae are
cord.
the many bones that protect the
nerves in the spinal cord. s that
protect the nerves in the spinal
•An automatic reaction that happens
without thinking about it.
•A body action that doesn’t involve
the brain because it is controlled by
the spinal cord.
•A reflex is a protective
action.
•It happens quickly in less
than a second.
* The brain controls everything in the
body.
* The brain is made of more than 10
billion nerves!
* The brain is divided into three
parts and is protected by the skull.
An organ that controls your
emotions, your thoughts, and every
movement you make.
* The Brain has three main parts…
1. The Cerebrum
2. The Cerebellum
3. Medulla Oblongata
( part of the The
Brain Stem)
* The Cerebrum is the largest part of
the brain.
1. The cerebrum controls your
thinking and reasoning.
2. The cerebrum controls
your memory.
3. The cerebrum controls
your speaking.
4. The cerebrum controls your
movement and identifies the
information gathered by your
sense organs.
* The cerebellum is below and to the
back of the cerebrum.
1. The cerebellum controls your balance.
2. The cerebellum controls your
posture.
3. The cerebellum controls the
voluntary muscles (voluntary
actions).
•The part of the Brain
Stem that connects
the brain to the spinal
cord.
• The nerves in the brain stem control
your involuntary actions---heartbeat,
breathing, and blood pressure.
* The PNS carries messages between
the central nervous system and the
rest of the body.
•The PNS’ job is to connect the Central
Nervous System to the rest of the
body.
•Nerves outside the CNS– 12 pairs of
cranial nerves and 31 pairs of spinal
nerves
•Divisions:
1.
Somatic Nervous System- controls
the actions of voluntary muscles like
the muscles of the arms, legs, & face.
2. Autonomic Nervous System- is
responsible for the functions of the
heart, lungs, glands, blood vessels,
and smooth muscles of the digestive
system.
* The outer nervous system
controls the body’s activities
that you don’t think about.
* The outer nervous system controls
activities in your small intestine, your
breathing, and your heartbeat.
controls
* The PNS is made of the nerves and
the sense organs.
Tongue
Eye
Ear
Nose
Skin
Nerves
Parts of the Nerve Cells/ Neurons
• Cell Body - center of the neuron which
contains the nucleus. It controls the nerve
cells.
• Dendrites – pick up impulses and carry
these to the cell body.
• Axon – carries impulses away from the cell
body to other neurons, to the muscles or
glands.
Parts of the Nerve Cells/ Neurons
How An Impulse Is Transmitted From
One Neuron To Another Neuron
Kinds of Neurons
• Sensory Neurons- carry impulses from the
sensory receptors to the CNS.
• Motor Neurons – carry impulses from the
CNS to the muscles and glands.
• Association/Interneuron Neurons – relay
impulses between sensory and motor
neurons.
- found in the CNS (brain and spinal cord)
How messages travel through the body?
• Stimulus received by the receptor cells 
converted to impulse  travels through 
sensory and association neurons  relay the
message to  brain or spinal cord 
processes information and sends signals to 
motor neurons  carry message to 
muscle/body part  carries out  response or
reaction
How messages travel through the body?
Sense organs
carry messages
about the
environment to
the central
nervous
system.
The eyes, ears, nose, tongue, and
skin are examples of sense organs.
The sense organs gather
information (light, sound, heat,
and pressure) from the
environment.
The environment is everything
outside the body.
The sense organs gather
information from outside the
body, then send the messages to
the brain.
Vision is your ability to see.
Vision involves the eye and the brain.
The eye is one of your sense organs.
The eye is made of the iris
and the pupil.
The eye gathers pictures and
sends them to the brain.
The colored part of the
eye is the iris.
The black part of the
eye is the pupil.
The pupil becomes
larger
and
smaller
as
Iris
Pupil
it controls the light
coming into the eye.
When a sound is made, the air
around the sound vibrates.
Hearing starts when some of the
sound waves go into the ear.
There are nine main parts of the ear.
1. Pinna
5. Anvil
2. Ear canal
6. Stirrup
3. Ear drum
7. Cochlea
4. Hammer
8. Eustachian tube
9. Auditory nerve
The pinna is the part of the ear
that you can see.
The ear canal is the tube between the
outside of the ear and the ear drum.
The ear drum is in the middle ear. It
vibrates when sound waves hit it.
The three smallest bones in the body, the
hammer, the anvil, and the stirrup,
are in the middle ear.
The hammer gets the vibrations from the
eardrum, then sends them to the anvil.
The anvil passes the vibrations to the stirrup.
The stirrup passes the vibrations
to the inner ear.
The Eustachian tube controls the amount
of pressure in the ear.
The inner ear is made of
the cochlea and liquid.
The cochlea is in the inner ear. The
cochlea looks like a shell.
The auditory nerve carries the
hearing information to the brain and
the brain tells us what we heard.
The ear works with the brain to
control your balance.
All of your movements are controlled
by balance and muscles.
The liquid in your inner ear is responsible
for your balance.
The liquid in your ear moves when we move.
The liquid movement sends information to the
brain to tell it how we are moving.
The sense of touch is located in the skin.
The nerves in the skin allow us
to feel texture, pressure,
heat, cold, and pain.
Texture is how something feels.
The nose controls your sense of smell.
The nose is able to smell 80
different kinds of smells.
Your sense of taste comes from the
taste buds in the tongue.
Taste buds are the parts on the tongue
that allow us to taste.
The four kinds of taste buds are
sweet, sour, bitter, and salty.
Tastes and smells work
together to make flavors.
Flavors are the tastes
of food and drinks.
DISEASES OF THE NERVOUS
SYSTEM
• Cerebral Palsy – it is
caused by a damage to the
brain of a newborn baby
during birth. Lack of
oxygen or injury usually
causes the brain damage.
The victims may have
trouble walking, speaking
and using his/her hands.
• Infantile Paralysis – also
known as poliomyelitis
(polio) – a disease
affecting the gray matter
of the spinal cord. It starts
with fever, headache, sore
throat and stomach upset.
This may result in
paralysis, which is most
common in lower limbs.
• Meningitis – infection
caused by germs.
Certain germs may
outsmart our body
defenses and spread
inside our body. Some
of these germs infect
the central nervous
system harming the
meninges and causing
meningitis.
• Parkinson’s
disease – this is a
progressive
disease of the
nervous system.
This disease
affects adults and
is characterized by
uncontrollable
shaking of the
limbs.
• Hydrocephalus –
is congenital or
present at birth. It
is characterized
by an
accumulation of
fluid inside the
skull.
•Amnesia
Amnesia is the complete
or partial loss of memory
due to brain damages/injuries.
a. Organic amnesia-is caused
by head injuries, severe
illness, old age, alcoholism ,
stroke.
b. Functional amnesia- caused
by trauma or stress
•Alzheimer's Disease
It is described as mild
memory lapses that
lead to permanent
memory
loss.
•Stroke
A stroke is a condition where
a blood clot or ruptured artery
or blood vessel interrupts
blood flow to an area of the
brain. A lack of oxygen and
glucose (sugar) flowing to the
brain leads to the death of
brain cells and brain damage,
often resulting in an
impairment in speech,
movement, and memory.
•Brain Tumor
Brain tumor is an abnormal
cell division in or on the brain.
It may arise from tissues
within the skull or spread
through the bloodstream from
tumors in some parts of the
body.
Proper Care Of The
Nervous System
• Proper Nutrition- balanced diet for right nutrients to think
quicker, have a better memory, and improved concentration;
vitamins B1-thiamin & B12 for proper functioning;
minerals (Ca, K, Na --for transmission of nerve messages & Fe
for Oxygen supply)
• Have sufficient sleep, rest, and recreation.
• No to alcohol, drug abuse, and smoking.
• Avoid falls and injuries that can cause injuries to your brain
and spinal cord.
• Learn to cope with stress.