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The Brain – Covering All Parts- Essay, Research Paper

The Brain – Covering All Parts-

INTRODUCTION

The human body is divided into many different parts called

organs. All of the parts are controlled by an organ called the brain,

which is located in the head. The brain weighs about 2.75 pounds, and

has a whitish-pink appearance. The brain is made up of many cells,

and is the control centre of the body. The brain flashes messages out

to all the other parts of the body. The messages travel in very fine

threads called nerves. The nerves and the brain make up a system

somewhat like telephone poles carrying wires across the city. This is

called the nervous system.

The nerves in the body don’t just send messages from the brain

to the organs, but also send messages from the eyes, ears, skin and

other organs back to your brain. Some nerves are linked directly to

the brain. Others have to reach the brain through a sort of power

line down the back, called the spinal cord. The brain and spinal cord

make up the central nervous system.

The brain doesn’t just control your organs, but also can think

and remember. That part of the brain is called the mind.

PROTECTING THE BRAIN

Twenty-eight bones make up the skull. Eight of these bones

are interlocking plates. These plates form the cranium. The cranium

provides maximum protection with minimum weight, the ideal

combination. The other twenty bones make up the face, jaw and other

parts of the skull.

Another way the brain keeps it self safe is by keeping itself

in liquid. Nearly one fifth of the blood pumped by the heart is sent

to the brain. The brain then sends the blood through an intricate

network of blood vessels to where the blood is needed. Specialized

blood vessels called choroid plexuses produce a protective

cerebrospinal fluid. This fluid is what the brain literally floats

in.

A third protective measure taken by the brain is called the

blood brain barrier. This barrier consists of a network of unique

capillaries. These capillaries are filters for harmful chemicals

carried by the blood, but do allow oxygen, water and glucose to enter

the brain.

THE DIFFERENT SECTIONS OF THE BRAIN

The brain is divided into three main sections. The area at

the front of the brain is the largest. Most of it is known as the

cerebrum. It controls all of the movements that you have to think

about, thought and memory. The cerebrum is split in two different

sections, the right half and the left half.

The outer layer of the cerebrum is called the cortex. It is

mainly made up of cell bodies of neurons called grey matter. Most

of the work the brain does is done in the cortex. It is very wrinkled

and has many folds. The wrinkles and folds give the cortex a large

surface area, even though it is squeezed up to fit in the skull.

The extra surface area gives the cerebrum more area to work.

Inside the cortex, the cerebrum is largely made up of white matter.

White matter is tissue made only of nerve fibres.

The middle region is deep inside the brain. It’s chief

purpose is to connect the front and the back of the brain together.

It acts as a “switchboard”, keeping the parts of your brain in touch

with each other.

The back area of the brain is divided into three different

parts. The pons is a band of nerve fibres which link the back of the

brain to the middle. The cerebellum sees to it that all the parts of

your body work as a team. It also makes sure you keep your balance.

them to the two brain hemispheres. The thalamus is located in between

above the lower brain and under the two hemispheres.

THE DIFFERENT SECTIONS OF THE BRAIN:

Most of the above mentioned parts of the brain were produced

early in evolution but the higher mammals especially humans went on to

produce a sort of “thinking cap” on top of these parts. This

“thinking cap” was divided into two different parts, the left

hemisphere and the right hemisphere.

If the left side of your brain is more developed like most

people’s are, you are right handed. On the other hand if the right

side of your brain is more developed, then you will be left handed.

The right side of your brain is more artistic and emotional while

the left side of your brain is your “common sense” and practical side,

such as figuring out math and logic problems.

THE CEREBELLUM:

One of the most important part of the Human brain is the

cerebellum. The cerebellum is involved with the more complex

functions of the brain and sometimes is even referred to as “the brain

within the brain”. The cerebellum acts as a control and coordination

centre for movement.

The cerebellum carries small “programs” that have been

previously learned. For example, how to write, move, run and jump are

all previously learned activities that the brain recorded and can

playback when needed. Every time you practice, the brain rewrites the

program and makes it better.

You may have heard the saying “practice makes perfect”. Well

this saying is not entirely true; another way of “practicing” is just

to imagine what you wish to do. Since the cerebellum can’t actually

feel, it will think that you are doing what your imagining and respond

by rewriting it’s previous program and carrying out any other actions

needed for that function. This is one why to explain wet dreams.

THE CEREBRAL CORTEX:

The cerebral cortex makes up the top of the two hemispheres of

the brain. The cortex is a sheet of greyish matter which produces our

thoughts, language and plans. It also controls our sensations and

voluntary movements, stores our memories and gives us the ability to

imagine, in short it’s what makes humans, humans.

IN THE FUTURE

Today many experiments are being conducted that may be break

through’s for the future. For instance “brain grafting” is one

procedure that may be used in the future. Brain grafting is to

transplant a very thin layer of brain skin from one person to another.

This would result in control of parkinson’s disease and other seizure

related diseases.

Another radical idea that has already been successfully been

tried on rhesus monkey’s is, brain transplants. The ethics and legal

problems for such a transplant would probably never let this operation

be performed on humans. This is because the person would not be the

same, would not have the same memories or the same abilities that the

host body had had.

The last idea of the future that we will list is called

“artificial hearing and seeing”. Artificial seeing is achieved by

planting sixty-four small electrodes in front of the visual cortex of

the brain. The electrodes are connected to a small camera that is

some where on the person’s ear. A computer is attached to the camera.

The computer sends the images from the camera directly to the

implanted electrodes. They flash as the picture from the camera, thus

enabling the person to somewhat see.

Artificial hearing is much more complicated then artificial

seeing. First a electrodes must be planted in the brain. Then

through a microphone a computer produces electrical pulses that are

then sent to the electrodes in the brain.

But as of yet these procedures are not practical first because

of the size of the computer, it cannot be taken out of the laboratory

second the cost of the package and third the risks involved.

CONCLUSION

After all of the work and research that we have done it is

very evident to us that the brain is one of the most wondrous organs

that humans could have. It guides us through almost every second of

our life. Even after exploring vast and distant sky’s to the

microorganisms that exist today, the brain has never ceased to amaze

us and probably never will.

BIBLIOGRAPHY

1. The Brain and Nervous System by Lambert, Mark

copyright Macmillan Education, 1988

2. The Brain and Nervous System by Parker, Steve

copyright Franklin Watts, 1990

3. Encyclopedia Britannica by Britannica, Encyclopedia Inc.

copyright Encyclopedia Britannica Inc., 1986

4. The Incredible Machine by Geographic, National Society

copyright Geographic, National Society, 1992

GLOSSARY

artificial hearing: When a person is able to hear but not naturally.

artificial seeing: When a person is able to see but not naturally.

blood brain barrier: A set of special capillaries that are only found

in brain. There purpose is to filter the blood so only oxygen,

glucose and water are able to enter the brain. Unfortuantly they

don’t prevent narcotics from entering the brain.

brain: An organ that is pinkish-white in appearance and is located in

the skull. This organ controls almost everything that the body does.

brain grafting: Brain grafting is the process of taking a thin layer

of brain skin from the donor and moving to new host.

brainstem: This is what the brain had used to be early evolution, but

now it only controls our basic functions such as breathing and heart

rate.

capillaries: Tiny blood vessels.

cells: What all living thing are built from.

central nervous system: This the brain and spinal cord put together.

Also see: brain, spinal cord.

cerebellum: This part of the brain makes sure that all of your body

works together. It also keeps your balance.

cerebral cortex: This is one of the most important parts of the

brain. It also is produces our thoughts, stores our memories, and

plans.

cerebrospinal fluid: This what the brain floats in.

cerebrum: The cerebrum is split in to two different sides. Left and

right. It is located at the front of the head.

choroid plexuses: These special blood vessels are what produce the

cerebrospinal fluid.

cortex: This is the outer layer of the cerebrum.

cranium: This is the part of the skull that holds the brain.

diseases: Illnesses that can be terminal.

electrodes: They are made out metal and emit electricity, usually

very little.

glucose: This is a combination of sugar and water.

grey matter: Mainly made from the cell bodies of neurons.

hemisphere: These are the two different part of the cerebrum. Almost

all of the brain’s work is done there.

hormones: Chemicals that can change the chemical make up of your

physical body.

hypothalmus: This part of the brain is located above the brainstem.

It controls basic drives such as hunger and sex.

medulla: The medulla is almost right behind the brainstem. It helps

you to digest your food.

mind: Not just the brain but the actual consciousness that we have.

nerves: Pathways that the brain uses to send messages to and from

different parts of the body.

nervous system: The whole system of nerves that attach to the spinal

cord.

organs: Important part of the body. The brain, heart and lungs are

examples of organs.

Parkinson’s Disease: This disease causes the victim to have seizures.

pituitary: The pituitary produces hormones.

pons: A band of nerve fibre that connect the back the brain to the

middle.

skull: The skull is made up of twenty-eight bones. It is located

above the spinal cord. It also contains the brain.

spinal cord: This cord goes down your back. Almost all nerves in the

body are connected to the spinal cord.

thalamus: The thalamus a sort of relay room. It gets messages from

the lower brain area and sends them to the higher brain.

transplant: To transplant is to take something from one person and

put it into another person.

white matter: White matter is tissue made from nerve fibres.