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TAY NGUYEN UNIVERSITY
FACULTY OF FOREIGN LANGUAGE STUDIES

ENGLISH FOR MEDICAL STUDENTS

DakLak, 2012

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TABLE OF CONTENTS
UNIT 1 CELLS..............................................................................................................................................................3
UNIT 2 BACTERIA......................................................................................................................................................8
UNIT 3 TISSUES: CELL SPECIALIZA TION.....................................................................................................12
UNIT 4 THE NERVOUS SYSTEM AND THE ENDOCRINE SYSTEM.........................................................16
UNIT 5 THE SKELETAL SYSTEM........................................................................................................................20
UNIT 6 THE CIRCULATORY SYSTEM...............................................................................................................26
UNIT 7 THE RESPIRATORY SYSTEM................................................................................................................32
UNIT 8 THE DIGESTIVE SYSTEM.......................................................................................................................37
UNIT 9 DISEASE: ITS SYMPTOMS AND CURES.............................................................................................41
UNIT 10 COMMON DISEASE AND AILMENTS................................................................................................45
UNIT 11 SURGERY....................................................................................................................................................49
UNIT 12 GOING TO THE MEDICAL CENTER.................................................................................................52
FURTHER READINGS
GLOSSARY

56
68

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UNIT 1

CELLS

There are several criteria for differentiating living from non-living things. One of these
is the presence of protoplasm. This jelly like material is always present in living things
and never in non-living things. Protoplasm is usually transparent and colourless. It
often has the appearance and consistency of the inside of a chicken egg. Protoplasm is
present only in cells and as necessary as cytoplasm. Without it, all cells would stop
living.
Most cells can be seen only with a microscope. They are microscopic in size. A few
relatively large and can be seen without a microscope. Cells are of various kinds and
properties. Some cells, for example, can move around the tissue, i.e. they are motile.
They move like the amoebae: they have the property of amoeboid movement.
Let's study the properties of the two most common cells: red blood cells (erythrocytes)
and white blood cells (leukocytes). Both erythrocytes and leukocytes are flexible. In
other words they can bend into many shapes. Neither of them is adhesive. Leukocytes
are phagocytic, i.e. they can destroy bacteria, whereas erythrocytes are not. Leukocytes
can pass through the capillary walls, however, veins, which are muscular, are
impermeable to them.

Platelets, or thrombocytes are small, regularly-shaped clear cell fragments (i.e. cells that do
not have a nucleus containing DNA). The average lifespan of a platelet is normally just 5 to 9
days. Platelets play a fundamental role in hemostasis and are a natural source of growth
factors. They circulate in the blood of mammals and are involved in hemostasis, leading to the
formation of blood clots.

Cells differ in shape as well as in size. But they are similar in composition and
structure. All cells are made up of protoplasm, and most of them have a nucleus, which

control the life activities in the cells. The nucleus determines whether a cell shall be a
bone cell, a muscle cell, or any of many kinds which make up the structure of the
body. In the cell nucleus lie the genes which pass on certain traits from one generation
to another. The protoplasm outside the nucleus is the cytoplasm. In plants and some
animals, cytoplasm often contains vacuoles. A vacuole is a cavity that is filled with

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watery liquid. Vacuoles hold food until it is digested and help eliminate excess water
from the cell.

A cell
Another structural similarity of all cells is the cell membrane that encloses the
protoplasm. Food entering the cell and wastes leaving it always pass through this
membrane. Some cells have cell walls outside their membranes. Composed of
cellulose, cell walls give strength and protection to the cells.
The body grows through cell division, each kind of cell dividing to take more of its
own kinds, and only its own kind. Cells also control, through a mechanism not yet
understood, the stopping of the growth at maturity
COMPREHENSION
A. TRUE/FALSE
1. Cells are always round.
2. Protoplasm is not always colorless.
3. Only cells contain protoplasm.
4. Cytoplasm is found outside the nucleus.
5. The cytoplasm in plants often contains cavities that are filled with liquid.
6. A platelet has a nucleus.
7. Plant cell walls are made of cellulose.
8. Not all cells are motile.

9. Erythrocytes are flexible whereas leukocytes are not.
10. Veins are permeable to leukocytes.
B. COMPLETION
1. Protoplasm is not present in ..................(animals, plants , cells, rocks)

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2. There is usually an absence of.............in protoplasm (material, colour, life,
consistency.)
3. The inside of an egg and protoplasm often have the same ............ ( consistency,
shape , size, liquid )
4. Some cells do not have .......... ( protoplasm, cytoplasm, a nucleus, membrane)
5. A nucleus is found in most ......... .. (membranes, cavities, material, cells)
6. Before it is digested, food is held in the cell by the ......:..... ( nucleus, vacuoles,
cellulose, protoplasm)
7. All cells are similar in that they each (are microscopic, contain vacuoles, have a cell
membrane, have a nucleus.)
8. Some white blood cells can destroy bacteria, i.e. leukocytes are ............ .. (motile,
adhesive, phagocytic, flexible )
9. Leukocytes are phagocytic ......................... erythrocytes are not. (as well as , on the
other hand, yet, whereas.)
10. All cells are .......in size (big, similar, alike, different)
11. The gene lie in ............ (the stomach, the cell, the heart, the cell's nucleus)
12. The body grows through........... (cell classification, an unknown mechanism, cell
division, cytoplasm)
C. QUESTION
1. What is one of the criteria for differentiating living from non-living things?
2. What is the protoplasm?
3. What are some special properties of cells?

4. What are some common kinds of cells that you know?
5. What does the word ' phagocytic" mean?
6. How are the cells alike?
7. What's the important function of the nucleus of the cell?
8. What pass on certain hereditary traits from parents to children?
9. How does the body grow?
10. How do cells control the stopping of growth at maturity?
D. WORD MEANING: Choose the words or phrases which have the closest meaning
to the word underlined
1. Glass is a transparent material.
a. dark b. clear
c. hard d. soft
2. Living things are composed of many cells.
a. separated by b. covered by c. made up of.
3. Vacuoles help to eliminate excess water from the cell.
a. draw in
b. remove
c. cut out d. aspirate
4. Food can pass through the cell membrane.
a. move from b. stay
c. go away from d. go through
5. Vacuoles hold food until it digested.
a. make
b. use
c. contain
d. eat
E. GRAMMAR: Adjectives to describe properties
Noun phrase + be+ adjective
Both erythrocytes and leukocytes are flexible.
Elastoplasts sticks to the skin. It is adhesive.


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The skin can bend into many shapes. It is flexible
I.
Fill the following sentences with the given words
bend
flexible pass through
phagocytic adhesive
amoeboid motile stretch
permeable elastic impermeable
1. Some cells can pass through capillary walls. In other words capillaries are
………….
2. Some white blood cells can destroy bacteria. They are ..............
3. Platelets are very small particles which stick together to stop bleeding, i.e. they
are .............
4. Erythrocytes can ........... to get through narrow blood vessels and then return to their
original shape. In other words, erythrocytes are ………..
5. Blood cells cannot pass through artery walls. This means that arteries are..............
6. Leukocytes can pass through capillary walls. This means that capillary walls
are .............to leukocytes.
7. Leukocytes can move around in the tissues. In other words, they are ……………
8. Veins are wide blood vessels with some muscle in their walls, i.e veins are
……………… (blood vessels)
9. Some cells move like the amoebae: they have the property of ...........movement.
10 Arteries are long, tubular blood vessels which can bend and stretch, i.e. they are
………… and ………..
11. Erythrocytes cannot pass through capillary walls. In other words, capillary walls
are usually.............

II. Using the above information, complete the following table.
flexible

phagocytic

motile

adhesive

erythrocyte
leukocyte
platelets
permeable
impermeable
muscular
elastic
arteries
capillaries
veins
III Linking words
Both… and, neither….. nor, but, whereas, however, on the other hand
Both erythrocytes and leukocytes are flexible.
Neither erythrocytes nor leukocytes are flexible.
Leukocytes are phagocytic, whereas erythrocytes are not.
but
Leukocytes are phagocytic. Erythrocytes, however,
are not.
on the other hand
Complete the following sentences
1. Both arteries and …………….. impermeable.


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2.
3.
4.
5.
6.
7.

Arteries are elastic blood vessels but …………………
Capillaries have very thin walls whereas …………………. muscular walls.
Neither …………………………………………. are phagocytic.
Platelets are ……………………………. erythrocytes are not.
Skin is ……………………….. . Bone ……………. is rigid.
……………. do not have the ………………. of amoeboid movement.
leukocytes ………. can ……..tissues.
8. Capillaries are permeable to ……… Erythrocytes, on the other hand
……………

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UNIT 2

BACTERIA

Very small organisms that can be seen only with a microscope are called
microorganisms. Some microorganisms are classified as animals, some as plants.

Bacteria (singular: bacterium) are examples of microorganisms that are considered
plants by most of biologists.
Although they are very small, bacteria are present in most places than any other kind
of organisms. They live in the ocean, on the desert and in the snow. They have been
found many kilometers high in the air, as well as at the bottom of rivers and lakes.
Bacteria also live in and on animals and plants. Although an individual bacterium
cannot be seen without a microscope, groups or colonies of bacteria can often be seen
with the naked eye.
Most bacteria have only one cell. This cell is spherical, spiral, or rod-shaped, and it is
usually covered by a strong cell wall. Most bacteria have a slimy capsule surrounding
their cell wall for additional protection. Many rod and spiral-shaped bacteria have taillike extensions of cytoplasm called flagella (singular, flagellum), which they use for
swimming. Most spherical bacteria do not have flagella.

A few kinds of bacteria are able to get the energy they need from certain chemicals
like iron and sulfur. However, most bacteria get their energy from plants and animals.
Bacteria that live on dead organism or on substances produced by living plants or
animals are called parasites. The organism on which the parasite lives is called the
host.

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Although some bacteria cause disease, most bacteria are very helpful. For instance,
when saprophytes feed on dead organism, they break down the organic material into
elements and compounds that can be used in the synthesis of protoplasm by other
organisms. Without bacteria, all life would eventually cease because these elements
and compounds would be tied up in the bodies of dead organism.
COMPREHENSION
I. Yes/ No answers
1. Are bacteria classified as animals by most scientists?

2. Can bacteria live in water?
3. Can group of bacteria ever be seen without a microscope?
4. Different kinds of bacteria have different shapes, don't they?
5. Are bacteria cells ever covered by anything other than a cell wall?
6. Are the host and the parasite the same organism?
7. Do saprophytes get their energy from iron and sulfur?
8. Most bacteria don't get their energy from inorganic substances, do they?
II. Completion Choose the best answer
1. Bacteria that live in living things are ...................
a. host
b. flagella
c. dead
d. parasites
2. The capsule outside the cell wall of some bacteria helps ...................
a. protect the cell b. give it energy
c. it swim
d. them avoid anger
3. Some bacteria...................
a. are organic b. have no cells c. are called hosts d. can cause disease
4. Most bacteria depend on ..............for their food.
a. other organism b. flagella c. saprophytes d. slimy capsules
5. Flagella are used for ...................
a. digesting food
b. attacking c. eating
d. moving
6. Certain bacteria feed on organic material that ..............other living things.
a. are helpful
b. are dangerous to
c. are synthesized by
d. are not microorganism

7. Without bacteria, all life would ...........,,,.,.
a. free of sickness
b. depend on photosynthesis
c. slowly stop
d. by synthesized
III. QUESTIONS
1. Where can bacteria be found?
2. When can bacteria be seen with the naked eye?
3. What is the use of slimy capsule surrounding the cell walls of bacteria?
4. Do all bacteria have flagella?
5. What are flagella and what are they used for?
6. What are parasites?
7. What is the host?
8. What would happen to life if there were no bacteria?
IV/ COMPLETION

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1. Although bacteria are very small, they are ..............other life on earth .
a. unimportant to b. less interesting to c- necessary to d. smaller than
2. Trees are organic materials, but .................. are not
a. animal bodies b. dead plants c. hosts
d. iron and sulfur
3. When the heart cease all activities, a person .................
a. need medicine b. is healthier
c. dies
d. gets thin
4. Most..................are rod-shaped
a. mountains b. pencils

c. clocks
d. roads
5. .................move their tails when they are pleased.
a. people
b. children
c. dogs
EXTENSION
USEFUL BACTERIA
Most of us think of bacteria as "germs" -- unseen threats to our health and welfare. But
for each of the few disease-producing kinds which can live in the human body, there
are hundreds of others upon which we depend for our very existence. Bacteria help us
digest our food. Without bacteria we would have no food.
They belong to the vegetable world, being minute one-celled colorless plants so small
that the dot over this "i" can cover nearly a million of some kinds. Some are rodshaped, some are round, some are corkscrew or spiral-shaped, and some have hair-like
whip-like filaments with which they swim actively in fluids. Most kinds multiply
by simply splitting in two: each bacterium dividing into two equal “daughter" bacteria
every 20 or 30 minutes, under favorable conditions. Though microscopic in size, they
can multiply so fast that, after a day and a half, the billions of billions of offspring of a
single one would load a long freight train -- if it were possible to feed so many. Under
unfavorable conditions, some kinds form thick-walled spores which can withstand
prolonged drying, extreme cold, and even boiling; and may lie inactive for days or
even years.
All animals depend upon plants, directly or indirectly. Plants depend upon the fertility
of the soil, which in turn depends upon bacteria. Inconceivable numbers of them
inhabit the soil -- roughly a billion per teaspoonful -- where some convert plant and
animal remains into humus and plant food, and others make the minerals in the
soil available as plant food. All decomposition and decay in the dead bodies of plants
and animals are caused by bacteria and their close relatives: molds, fungi and yeasts.
Our huge garbage dumps are decomposed by them. Our modern methods of sewage
disposal employ speeded-up bacterial action to rapidly break down and

oxidize household and industrial wastes. Nothing escapes these scavengers. They are
in the ground, in the water, in the air -- everywhere.
Nitrogen in the form of nitrates is an essential plant food frequently lacking in soils.
Nitrogen from the air is inert and difficult to change and combine with other
substances, but certain bacteria have the rare ability to absorb it and change it into

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forms which other plants and animals can use. Some of these nitrogen-fixing bacteria
live in nodules or lumps on the roots of legumes such as clover, alfalfa, peas,
beans and locust trees.
Fermentation, as when wine and cider turn into vinegar, is caused by bacteria. Of
hundreds of different kinds, a few of the common bacteria are those used to make rye
bread, sauerkraut from cabbage, pickles from cucumbers, silage from corn, linen from
flax, glycerin, citric acid, lactic acid, and dairy products.
Fresh warm milk is an ideal food for many kinds of bacteria, especially the common
one which causes milk to sour and curdle. Cream so soured and ripened is easily
churned into butter. Cottage cheese is made from sour milk. Most cheeses are made
from curds produced by treating milk from cows, sheep or goats with "rennet", a
digestive ferment. The ripening, and the different textures and flavors,
are accomplished by various pure cultures of bacteria and molds which are added to
the curd as "starters", depending also upon special conditions of air, moisture and
temperature. Some extremely hard Italian cheeses contain little water and are
correspondingly slow to ripen. "Soft" cheeses contain more water and ripen more
rapidly. The blue-green mold of Roquefort is due to powdered bread mold sifted into
the curd. The holes in Swiss cheese come from gas generated by bacteria.
The bacteria in Limburger are little stinkers.

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UNIT 3
TISSUES: CELL SPECIALIZA TION
The cell is the fundamental microscopic building of all living matter. The human body
is made up of millions of cells. Each one has a special task within the body. Cells
usually do not work alone. Groups of cells of the same type that do a particular kind
of work are organized into tissues.
Growth is one of the criteria by which we differentiate between living and non- living
things. Growth begins to occur when a cell in one living thing increase in size or
number. Individual cells do not increase in size very much, even when they are mature,
almost all cells are microscopic in size. Therefore, growth usually involves an increase
in the number of cells.
As living things grow, they usually become more complex. The cells become
organized into tissues to perform different life activities. There are several kinds of
tissues in most higher plants and animals. For instance, in the human body there are
four basic types of tissue, epithelial, connective, muscular, and nervous.

The outer layer of skin is composed of epithelial tissue, also called epithelium.
Epithelium also forms glands and lines organs inside the body, such as stomach.
Connective tissue serves the important function of connecting other tissues to each
other and to the bones of the skeleton, which support and protect the body. The
skeleton itself is built of a special kind of connective tissue. Another type of
connective tissue produces blood cells. Connective tissue also connects those muscle
cells to bones.
Muscles make possible all of the movement necessary for life activities. Muscular
tissue is composed of long, thin cells, or fibers, which can contract and relax. Groups
of muscles work together to perform a body motion. These muscles can be classified
as smooth or striated, depending on what they look like under a microscope. Two


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groups of muscles that work together are called antagonistic grows. For example, flex
your forearm, bending it toward your shoulder. Your biceps contracts or shortens, and
the triceps relaxes. Extend your forearm. The biceps muscle relaxes while the triceps
contracts. Flexion and extension are two terms you should know. Two others are
abduction, which means moving a part away from the body, and adduction, which
means moving it toward the body.
Muscle is the most infection-free of all the body’s basic tissues. This is largely because
of its rich blood supply. Muscles not only move the body but also help to keep the
body warm, especially during activity. If a muscle is kept inactive for too long, it tends
to shrink and waste away. This is called atrophy
Nervous tissue makes up the brain, spinal cord and nerves. Nerve cells receive stimuli
from inside and outside the body. They conduct these stimuli to the brain and the
spinal cord. In response to the stimuli, impulses are sent out to the muscles and glands.
This causes the muscles to contract or relax and the glands to secrete or stop secreting
fluids.
When similar cells are organized into one group, they are called a tissue. Several
different tissues organized into a large group form an organ. It is composed of four
types of a tissue found in the human body. When a group of organs work together to
perform one general function, they form a system. The nervous system, composed of
the brain, spinal cord and nerves, is the most complex of all the body systems.
COMPREHENSION
A. True/ False
1. Complex living things have groups of cells that can perform special functions.
2. Growth in living things usually occurs through the production of more cells.
3. Tissues often are composed of only one cell.
4. Few higher plants and animals have more than one kind of tissue.
5. Epithelium is present only on outer surfaces of the body.

6. Connective tissue cells serve the same function as epithelial cells.
7. Nervous tissue is composed of cells that are specialized to contract.
8. Stimuli are carried to the brain before they go to muscles and glands
9. Glands respond to nervous impulses by secreting fluids.
10. Living things having specialized cells are considered to be more complex than
those with unspecialized cells.
B. Completion:
1. Contraction of a muscle is a response to ..................
a. stimuli
b. fibers c. glands
d. growth
2. The stomach is .................
a. an organ
b. a gland c. epithelium tissue d. the skeleton
3. Connective tissue does all of the following except......................
a. connect other tissue to each other
b. support and protect the body

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c. produce blood cells
d. connect stimuli to glands
4. Most animals are able to move around because ......................
a. they are organized into different groups
b. They have cells which can contract
5. Each kind of tissues ..................
a. serves special functions
b. can be found in every organ
c. covers and lines parts of the body

d. can contract and relax
6. Nervous tissue does not.................
a. connect tissue to bones
b. receive stimuli from outside the body
c. conduct impulses to muscle cells
d. cause gland cells to secrete
7. Muscles and glands receive .................from the brain and spinal cord.
a. contraction b. secretions
c, fluids
d. impulses
8. All of the organs in the body are composed of..................
a. muscle
b. epithelium tissue c. specialized cells d. system
9. Living things become more complex when..................
a. the cells mature and die
b. the cells are destroyed
c. there are no organs
d. there is cell specialization
10. When you flex your forearm, your biceps ……….
a. contracts
b. relaxes
c. bends
d. extends
C. Questions
1. What form a tissue?
2. What are the four basic types of tissue?
3. What does epithelium do?
4. What is the function of connective tissue?
5. Why is muscle the most infection-free of tissues?
6.What is atrophy?

7. What makes up the brain, spinal cord and nerves ?
8. What makes up an organ?
9. What comprises a system?
D. Word meaning
1. The inside of the stomach is LINED WITH a mucous membrane.
a. covered on top with b. combined with c. made of d. covered inside with
2. Water is a FLUID
a. a chemical
b. a substance
c. a mixture d. a liquid
3. Dr. John has just RECEIVED a call from the hospital.
a. given
b. returned
c. answered d. got
4. Some materials CONDUCT electricity better than others.
a. control the strength b. differentiate between the kinds
c. permit the movement of d. break down and synthesize
E. Completion: Fill the blanks with proper words given below.
blood
brain
fibers
function
glands impulses
responds skin
spinal cord stimuli
stomach system
1. The ............... runs from the brain to the lower part of the back.

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2. ...................... is an essential liquid in the body.
3. A tree is made up of thousands of strong.....................
4. Food is broken down for the use of the body in the ..................
5. When a driver stops a red light, he is responding to ..................
6. Staying in the sun too long will make the ....................dark.
7. Which................. of the body has the function of eliminating waste.
8. The most important........ of food is to provide energy for the body.
9. Small ................. in the mouth release fluids that help break down food.
10. The ...........makes it possible for a man to think and to learn.

15

,


UNIT 4

THE NERVOUS SYSTEM AND THE ENDOCRINE SYSTEM

Your body's communications Net-work

All living things are able to take note of and respond to various factors in the
surrounding world. This ability depends on a highly organized system called the
nervous system. This system consists of the brain and the spinal cord and is known as
the central nerves system. Connected with the brain and spinal cord are peripheral
nerves including the twelve cranial nerves, which arise in the brain and serve mostly
the sense organs.
Another part of the body's communications network is the automatic system. This
system affects the automatic or involuntary actions of the internal organs, such as the

heart, blood vessels, lungs, stomach, intestine, kidneys, bladder and sweat glands.
An important function of the nervous system is to pick up sensations of light, sound,
touch, taste, heat, cold, pain... etc....... These sensations are carried from sense organs
to the brain over the sensory nerves. The brain receives these messages of sensations
and reacts to them, makes plans, and sends orders to for action. These orders are
carried by the motor nerves to the muscles of a particular part of the body. Thus the
brain is the control center of the entire nervous system. It is a soft, spongy mass of
tissue surrounded and protected by the bones of the cranium. Both brain and spinal
cords consist of two kinds of nervous tissue called grey matter because of nerve cell
bodies, white matter is made up of nerve fibers.
Sense organs contain specialized endings of the sensory neurons. These are activated
by sudden changes in the outside environment called stimuli.
Remember, the sense organs must send their messages to the brain and receive
directions how to respond to the stimuli. If this pathway is not intact, the sense organ
cannot function and the patient loses the use of it. For example, if the nerve pathways
to the eye are damaged; the patient will not be able to see.

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NERVE CELLS - The basic unit of the nervous system is the nerve cells or neuron.
Like all cells of the human body, the neuron contains a nucleus which is surrounded by
cytoplasm. All neurons are, however, distinguished from other body cells by thin fibers
or extensions, called dendrites and axon. A neuron may have many dendrites, but each
neuron has only one axon. Dendrites are the parts of the nerve cells that receive a
stimulus from any part of the body. The stimulus passes into the nerve cell and then
into the axon. The axon carries the impulse along to the dendrite of another nerve cell.
The nerve fibers of the connecting nerve cells do not meet or even touch each other at
their points of connection. They communicate their impulse chemically across gaps
called synapses.


The tiny cell body is the vital part of the cell though it is the least conspicuous part. If
it is destroyed, it cannot be repaired. But if an axon or dendrite is cut, it will often heal
and function again.
When part of the brain is damaged, as in a stroke or accident, either the path along
which impulses travel or the brain itself is damaged. If possible, another part of the
brain or impulse pathway can be trained to take over the function of the part that has
been damaged. Remember that nerve cells do not grow back once they die. You will
work with the rehabilitation department in your hospital, helping patients learn to do
things again after such damage has occurred.
KINDS OF NERVES - The sensory nerves carry stimuli from the various sense organs
to the brain. Motor nerves carry impulses from the brain or other nerve centers to. the
muscles. A third kind of nerves are associative or connecting nerves. These nerves
serve as connections between each other and between sensory and motor nerves.

17


The nervous system plays a vital part in our life activities. Without it our ability of
taking note of or respond to various factors in the surrounding world is entirely
destroyed and useless.
Hormones and the Endocrine System
The endocrine glands secrete liquids called hormones into the bloodstream. These
chemicals are secreted in one place, but work in another. The organs that manufacture
the chemicals are called endocrine glands.
The endocrine gland works by a “feedback mechanism”. When the body requires more
of a specific hormone, the gland supplies it. When the level is high enough, production
stops. This is a very sensitive balance. If it is not perfect, the body produces too much
or too little of a hormone. This results in some body misfunction. Through the
feedback mechanism, the endocrine glands regulate bodily functions and interact with

other system, - to keep our bodies working at their best.
QUESTIONS
1. Does the nervous system consist of only the brain and the spinal cord?
2. Does the automatic system affect the automatic or involuntary actions of some
internal organs, such as the heart, blood vessels, lung ....?
3. Are sensations of light, sound, touch ..... carried from sense organs to the brain over
the motor nerves?
4. Is the brain the control center of the entire nervous system?
5. Does Grey matter consist largely of nerve cell bodies?
6. Does the neuron serve as the basic unit of the nervous system?
7. Does each neuron have more than one axon?
8. Will an axon heal and function again if it is cut?
9. Is the dendrite the branching part at the receiving end of a nerve cell?
10. Is the cerebellum located in the lower back of the brain?
11.Are hormones secreted by endocrine glands?
12. Do hormones work in the same place where they are secreted?
PRACTICE
Word meaning: Write the word on the line before the corresponding definition
Receive
Neuron
Heart
Consist of Conspicuous
Motor nerves
synapse
Nervous system
Endocrine system
Entirely
hormones But for
blood stream
1.

2.
3.
4.
5.
6.
7.

The basic unit of the nervous system.
The vital organ of the circulatory system.
Take something offered or sent.
Include
A combination of nerve cells.
Places where a nerve impulse passes from one nerve cell to another.
Easily seen.

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8. Those nerves that carry impulses from the brain or other nerve centers to the
muscles.
9. The blood as it flows around your body
10. a chemical substance produced by your body that influences your body’s
growth.
11. Without
12. Completely
13. The system of glands that secrete hormones
Definition meaning
1. The highest nervous structure which organizes and control the body activities
(b.........................)
2. The main part of the human brain, occupying the upper portion of skill activity

and is the center of the higher mental faculties such as memory, responding,
judgment, intelligence, and the emotions (c...................)
3. The part of the brain that is located in the lower back of it. It helps control and
balance muscular activity (c.............................)
4. The lowest part of the brain system ,continuos with the spinal cord concerned with
regulating action and vital organs (m......................)
5. The thick, whitish cord of nerve which extents from the medulla to the second
lumber vertebra (s................c........................,).
6. Place where a nerve impulse passes from one nerve cell to another
(s....................)

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UNIT 5

THE SKELETAL SYSTEM

Your body's framework

The human body consists of many bones and substance resembling bone known as
cartilage or gristle. The primary purpose of skeleton is to support the body. The bones
are held together by tough tissue called ligaments.
Bones have another important function besides support. They protect vital organs of
the body. The skull, which is the bone cell, gives the protection to the brain. The spinal
column, or "back bone " is made up of 33 small bones called vertebrae which
completely encase or surround the spinal cord.
The ribcage has 12 pairs of ribs. The ribs are attached to the spinal column. Then they
curve around to the front, where 12 pairs fasten themselves to the sternum or


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breastbone. The ribcages protects organs in the thoracic area such as the lungs and the
heart.
TYPES OF BONES - There are more than 200 bones in the human body at maturity.
They are of three principle types _ long as in lower arms, the thighs, and legs, and
collarbones. The breastbones, the ribs, and certain bones of the skull are called flat
bones. Irregular bones are of many different sizes and shapes. Some irregular bones
are found in hands, feet, ears, pelvic girdle and spinal column.
STRUCTURE OF BONES - Bones contain living cells. The hard outer portion of the
bone contains special cells called osteocytes. This outer bone is largely made up of
mineral called calcium. The active portion of the bone is the material inside, called
bone marrow. The marrow looks like a sponge. These active cells manufacture the
hard outer layer of the bone and red blood cells. Certain types of white blood cells are
also made by the marrow.
More than 20 percent of the weight of living bone is water. Of the remaining 80
percent, about 75 percent is minerals and 25 percent organic matter. However, newly
formed bones may have a considerably higher percentage of organic material in
relation to minerals.
The minerals are salt or compounds of calcium, phosphorus, magnesium, and other
elements. These salts deposits greatly strengthen the tough organic matrix, the
foundation of the bone.
The organic matrix is about 97 collagen, a type of protein fiber that is also found in
tendons, skin and connective tissue. The remaining 3 is a cement-like substance, called
ground substance, which is composed of extracellular fluid plus a sulfate and an acid
compound.
OSTEOBLASTS.
One type of cell is the osteoblast, which is associated with the construction or
deposition of new bone material and the repair of broken bones. Osteoblasts are found

on most surfaces of the bones and in many cavities. The osteoblasts secrete an organic
material which, after being secreted combine mainly to form the collagen fibers which
make up organic matrix of the bone.
A small amount of osteoblastic activity occurs continually in all living bones so that at
least some new bone matrix is constantly being formed. The matrix in turn possesses a
special property, which causes calcium phosphate (Ca PH04) precipitation. During this
early mineralization of bone, these initial deposits of calcium and phosphate are
gradually transformed into a more permanent type of calcium salt. This transformation
into the harder and more durable crystals requires anywhere from several weeks to
months.

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HOW BONES GROW - Your bones grow thicker as you get older. The thin covering
the outside of the bones put down hard new bone cells to make the bone thicker and
stronger. Your bones also grow in length. During your growing years, the end of your
long bones is fastened to the bone shaft, mainly by a wide cartilage plate known as the
growth plate, or epiphysis. Gradually bone cells come up from the shaft and start
destroying the cartilage cells and putting down hard new cells in their place. The
cartilage cells are then forced to move out toward the ends of the long bones. As the
cartilage grows out, your long bones grow longer.
When a bone is broken, healing takes place through the action of the bone making
cells in the bone and its covering membrane.

Broken or fractured bones usually can mend solidly, but the process is slow and
gradual. Bone cells grow and reproduce slowly compared to other types of cells. The
hardening of the new bone is a gradual process of depositing calcium. As we age, our
bones become more brittle. The blood supply is often decreased, calcium is not as
readily stored, and the body's powers of general resistance to infection and healing are

decreased. For this reason an elderly person who breaks a bone will require a longer
time to heal than a younger person. In addition, when an elderly person falls, because
his bones are so brittle, he is more subject to fractures than a younger person.
JOINTS - Places where bones come together are called joints. Some joints are
movable while others are immovable. Immovable joints are called fixed joints, for
example, those in the cranium.
Some movable joints have more movements than others. Two of the most familiar
types of movable joints are the ball-socket joints as in the shoulder and hip, the hinge
joints, as in the knees, fingers and toes. Another type of movable joints is the pivot
joint. Pivot joints in the body are combined with the hinge joints.
Joints are held together by ligaments, muscles, and tendons. Ligaments are tough
stringy bands which hold the bones together, tendons join the muscles to the bones.
The joints in the shoulder, hip, and knee are each enclosed in a strong capsule lined by
a membrane that secretes a lubricated fluid. Movable joints are constructed so that two

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ends of the bones do not rub against each other. A pad of cartilage at the end of the
bone absorbs jolts, and cushions the bone ends. Injury to joints may cause a ligament
or tendon to be strained in what is called a sprain.
COMPREHENSION
I/TRUE/FALSE:
1. The human body is supported by ligaments.
2. Osteocytes are cells in the hard layer of the bones.
3. The tissues which hold bones together are weak.
4. The backbone is made up of 33 vertebrae.
5. Irregular bones are generally found in the hands, feet, pelvic, girdles, etc.......
6. The active cells of the bones are located inside the bone itself.
7. The bone marrow manufactures the white blood cells of the body.

8. Bones are composed of water, minerals, and organic matter.
9. Most of the weight of the bone is water.
10. Osteoblasts are found on the inside and outside of bone.
11. Osteoblasts are cells which dissolve bone.
12. Calcium aids in the development of the hard portion of the bone.
II/ COMPLETION
1. The special cells in the bone are called..........
a. marrow
b. active cells c. osteocytes
d. lymphocytes
2. The active portion of the bone is ..............
a. around the bone b- around the ligaments
c. outside the bone d. inside the bone
3. The inside portion of the bone is called.................................
a. a sponge
b. red blood cells
c. joints d. marrow
4. The knee and the elbow joints are ...................
a. slightly movable b. very movable
c. immovable
5. Calcium is produced in...................
a. bone marrow
b. red blood cells c. joints d. osteocytes.
6. The vertebral column.................. the spinal cord.
a. divides
b. completes
c- goes around d. holds up.
7. The ribcage is attached in the front to the ...............
a. rib
b. sacrum

c. back-bone
d. sternum
8. The thoracic cage must be movable to allow the lung to ...........
a. collapse
b. relax
c. contract
d. b and c
9. The ribcage is ...........
a. square
b. straight
c. curved
d. triangular
10. The brain is ..................
a. a shell
b. an organ
c. a cord
d. a vertebral
III QUESTIONS
1. How many bones are there in the body?
2. How bones are held together?
3. What is the ribcage composed of and what function does it serve?
4. What are the three principle types of bones?

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5. Where are irregular bones found?
6. What does the hard outer portion of the bone contain?
7. What is the use of calcium?
8. What's the marrow?

9. What are joints and how many kinds of joints are there?
10. What cushions bone ends?
PRACTICE
Word meaning Replace the capital words with those from the text that has the
same meaning:
1. Our body is HELD UP by the skeleton.
2. The MAIN purpose of the skeleton is to give support to the body.
3. The SPINE is BUILD UP OF 33 small bones called vertebrae
4. Of the twelve pairs of ribs, ten pairs fasten themselves to the BREASTBONE.
5. The SKULL, which is a shell, MADE UP OF BONE, gives protection to the brain.
6. The hard outer portion of each bone contains special cells called BONE
MAKING CELL.
7. The marrow RESEMBLES a sponge.
COMPLETION
Complete each sentence with a proper word.
1. The special cells in the bone are called ................
2. The outer portion of the bone is very ..............................
3. The inner portion of the bone is called ..........................
4. The vertebral column ...............the spinal cord.
5. The ribcage is attached in front to the ............................
6. The bones protect.................. ..organs of the body .
7. The thoracic cage must be .................. ..to allow the lungs to contract.
8. Calcium, which is a......................,is necessary in the development of the body.
9. Ligaments are made up of..................... ..tissue.
WORD FAMILY
Complete the sentences with words related to the word move.
a. move (v)
d. motion (n)
g. movable i. movement
b. motion (v)

e. immovable
c. moving (adj)
f. motion picture
h. motionless
1. Abduction means ……………..a part away from the body.
2. Voluntary muscles are those we ……………..consciously.
3. A hall-and-socket joint, such as the hip joint, allows a very wide range of motion. It
is a freely ______ joint.
4. The muscular system makes all ______ possible.
5-6-7. Bones are the passive organs of (5)_____ They do not (6) ______ by
themselves. They must be (7) _______ by muscles.
8. The joints between the bones of the head that protect the brain do not move at all.
They are_____ joints.

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9. Be very careful when changing lanes in fast ______ traffic.
10. The patient sat staring out of the window, quite ___________
11. Muscles function to allow _____ .
12. Joints, which are formed where bones meet, allow the body to ______ .
13. ______ is both an art and an industry.
14. The teacher ______ to her to be quiet.
15. The clock got broken during the ______.
16. Jackson's speech was so ________ that it made me cry.

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