lesson for grade 9 science the topics includes: (a)respiratory system, (b) circulatory system, (c) other organs working together with the respiratory and circulatory system

1. First Quarter
Living Things and Their
Environment
a)Respiratory System
b) Circulatory System
c)The Circulatory System and the Excretory
System
By: Victor Rea oribe
Manuel S. Enverga University Foundation, Lucena
City, Philippines

2. Respiratory and Circulatory Systems Working
with the other Organ System
Content Standard Performance Standard Learning Competency
The learners
demonstrate an
understanding of:
The learners should
be able to:
The learners should
be able to:
1. How the different
structures of the
circulatory systems work
together to transport
oxygen-rich blood and
nutrients to the different
parts of the body
conduct an information
dissemination activity on
effective ways of taking
care of the respiratory and
circulatory system based on
data gathered from the
school or local health
workers.
1. Explain how respiratory
and circulatory systems
work together to transport
nutrients, gases, and other
molecules to and from the
different parts of the body;
2. The prevention,
detection, and treatment
of diseases affecting the
circulatory and
respiratory system.
2. Infer how one’s lifestyle
can affect the functioning
of respiratory and
circulatory systems.

3. Why do we breathe?
Why does the heart beat?
Why is oxygen essential
to life?
Essential Questions

4. Assessing Prior Knowledge
What is oxygen?
Why do we breathe?
What causes humans to grasp
for air?

5. Why We Need Oxygen
What is oxygen?
O8
Chemical symbol
atomic number
O2
Atmospheric oxygen

6. Oxygen serves as an essential element
supporting life and as an integral part of the
atmosphere.
Oxygen plays a vital role in carrying out
metabolic functions of cells; and
because of this,
a) its presence enables us to live.
b) it facilitate the breakdown of
nutrients essential for supporting
growth and development.

7. Without metabolism, our body will deteriorate.
This will result to death. Why?
Because our body cannot process the nutrients needed
for maintaining life.
In the absence of oxygen, mortality becomes apparent as
other physiological processes in the body becomes
jeopardized.
The impaired metabolic function due to lack of oxygen
in the body will result in susceptibility to infections as
the breakdown of specified nutrients for the immune
system becomes impaired.
We may also feel weakness due to the body’s inability to
break down glucose for energy, which as a result will
ultimately make the other organs incapacitated, thus
leading to death once the supply of oxygen becomes

8. Why do we breathe?
Examine these pictures. Between
the two activities, which one
consumes more oxygen?
With this activity, we feel that
our chest burst out in order to
supply our body with high
amount of air.
This means that, as we utilized
energy, our demand for oxygen
increases.

9. In a normal functioning individual, air enters the
body through the process known a breathing.
Breathing is defined as the act of pulling air
into the lungs (inhalation) and eliminating air
out of the lungs (exhalation)
The air that enters the body includes all the
components of air including dust, dirt, trace gases,
and oxygen.
Oxygen is absorbed by the blood in exchange for
carbon dioxide, which is a product of energy
production in cells and is released during
exhalation.

10. During strenuous activity, the body breaks down its food
source to produce energy.
In order to convert food to energy efficiently, oxygen is
required.
Energy production utilizes oxygen and releases carbon
dioxide as a product.
As the activity progresses, the body may lose its supply of
oxygen and the person tries to gasp for air in order to get
more oxygen.

11. Arrange the following activities according to the degree
they require you to consume oxygen. 5 being the highest
and 1 the lowest. Assume that each activity is done for 10
minutes.
________writing on your notebook
________ playing basketball
________ singing
________ walking to school
________ blinking of your eye
Explain your answer.

12. The Respiratory System
Respiratory System is responsible for getting
Oxygen from the atmosphere and bringing it to our
Lungs.
This system is
generally
comprised of the:
Nose
pharynx
larynx
trachea
lungs

13. Respiratory system also allows for the filtration,
humidification, and warming of the air when
it enters the nostrils and the air passages.
Respiratory system minimizes the harmful content of the
air reaching the lungs before gas exchange takes place in
the body.
The Respiratory System is divided into upper and
lower respiratory tracts.

15. The Upper Respiratory Tract
Nose
It is the only part of the respiratory system that is visible
extrinsically.
It is the only part of the respiratory system that is visible
extrinsically.
Without our nose, a lot of physiological activities in the
body will be impaired.
 We will not be able to enjoy the appetizing smell of
our favorite food.
 We will not be able to enjoy the fragrance of a
cologne or perfumes we desire to wear.

16. Most importantly, without our nose, we cannot breathe in
air normally.
Our nose serves as the main entry for air flow in the body.
Air is warmed, filtered, and humidified in the nose to get
rid of foreign particles that can irritate or harm the lungs.
Our nose also serves as the exit for carbon dioxide.

17. Pharynx
The Upper Respiratory Tract
Also known as the
Throat, that serves as
the pathway for air and
food.
Air enters the
nasopharynx from
the nasal cavity then
travels down through the
oropharynx then
laryngopharynx to
enter the larynx below.

18. Food comes in through the mouth and passes along with
air through oropharynx and laryngopharynx.
The food
heads
toward the
esophagus
posteriorly
rather than
arriving at
the larynx

19. Other tissues present in the Pharynx include tonsils.
These tissues consist of three types:
Pharyngeal
tonsil often referred to as
the adenoid, lies high
in the nasopharynx.
Palatine tonsil
 Located in the
oropharynx at the
end portion of the
soft palate.
Lingual tonsil
 Situated at the base of the tongue.

20. The Lower Respiratory Tract
Larynx
The thyroid cartilage, which
projects toward the front of the
throat and is often referred to as
Adam’s apple, is the biggest
of the hyaline cartilages.
Larynx leads air into the appropriate channel and
functions mainly in speech.
It is situated below the pharynx, it is made up of eight
hyaline cartilages and a spoon-shaped elastic cartilage, the
epiglottis.
The food heads toward the esophagus posteriorly rather
than arriving at the larynx

21. The epiglottis in our larynx functions as a protective
barrier for lungs as it prevents food from reaching the
lungs.
Upon swallowing,
our epiglottis
moves in a fashion
that forms a
covering for the
larynx and trachea
so that food will
enter the esophagus
instead of the air
passage.

22. If other particles aside from air enters the windpipe,
coughing reflex is produced to remove the substance.

24. Trachea
The Lower Respiratory Tract
The trachea is also known as windpipe.
The trachea’s structure adjoins the esophagus enabling it
to extend anteriorly when we swallow.
Trachea plays an important role in normalizing the
function of epiglottis and permitting food passage to the
esophagus.
The trachea also consists of ciliated mucosa that
transports mucos contaminated with foreign particles
away from the lungs toward the throat, where it can be
swallowed or ejected through spitting.

25. The Lower Respiratory Tract
Main Bronchi
The left and right
main bronchi are
formed by the
division of trachea.
The left bronchus is
narrower, longer,
and less straight
than the right.
With this structure, the right main bronchus has the higher
tendency for any foreign object to be placed.

26. Upon entering the main bronchi, the air is already moist,
devoid of all foreign particles, and warm.
The tinier
branches of the
main bronchi
within the
lungs lead to
the air sacs.

27. The Lower Respiratory Tract
Lungs
Divided into two
portions, the lungs are
composed of lobes.
The left lung is made
up of two lobes while
the right lung is made
up of three.
The lungs almost cover the entire thoracic cavity, and this
organ holds the respiratory zone, the only place where gas
exchange happens.

28. The respiratory zone includes:
 Bronchioles
 Alveolar duct
 Alveolar sac
 Alveoli

30. Physiology of Respiration
The breathing mechanism is designed to get
oxygen into the bloodstream so that it can be
distributed to all cells of the body where food
molecules are broken down to produce energy in
the presence of oxygen.
To supply the body with oxygen, the respiratory
system carries out the four major actions:

31. 1. Pulmonary ventilation:
Also known as breathing, is the process in which air
moves in and out of the lungs.
2. External respiration:
This is the process in which carbon dioxide from the
cells is expelled from the lungs as the blood in the
lungs picks up a fresh load of oxygen.
In this phase, gas exchange takes place between the
blood and the external body.
3. Respiratory gas transport:
Oxygen and carbon dioxide must circulate the
bloodstreams to reach the lungs and tissues.

32. 4. Internal respiration:
Gas exchange must occur between the tissue cells
and the blood in systemic capillaries.
In this phase, air exchange are taking place
between
the cells in the interior aspect of the body and the
blood.

34. Assignment
1. Which structure of the upper respiratory tract serves as
the passageway for both food and air?
2. Which structure of the larynx prevents food entrance to
the lungs?
3. How do the lungs get rid of particles that accidentally
enter the air passage?
4. Differentiate the four major actions of the respiratory
system.
5. Describe the two roles of the windpipe or trachea.
6. How does the trachea aid in expelling mucus that may
be contaminated with foreign particles?

35. The Circulatory
System
What happens once the air becomes
processed by the respiratory system?
Alone, can respiratory organs supply the
every cell in our body with oxygen?

36. As the respiratory system initiates gas exchange
within the body, the circulatory system supplies
oxygen in our cells.
The pumping action of the heart and the network of
channels are responsible for carrying and distributing
nutrients, gases, hormones, antibodies, and many other
important substances that the body needs to live.
The rhythmic contraction and relaxation of the heart is
what produces the sound we all know as heartbeat.
The heart work tirelessly all throughout our lives and
never stops to rest.
Can you imagine what can happen when the heart rests?

37. The Circulatory System is divided into three
major parts:
 The Heart
 The Blood Vessels
 The Blood

38. The Heart and Blood Vessels
One of the most amazing and most complex organs in the
body.
It is highly muscular organ
and is the size of our fist.
It pumps blood throughout
the body by way of
involuntary contractions of
the cardiac muscle.
The heart is located in the
center of the thoracic or
chest cavity, slightly toward
the left.

39. The heart has four chambers:
a) Right atrium
b) Right ventricle
c) Left atrium
d) Left ventricle

41. four valves of the heart
a) Tricuspid valve
b) Pulmonary valve
c) Bicuspid valve
d) Aortic valve

42. They often and close with
precise timing to make
the heart pump blood
effectively
The tricuspid and the
bicuspid valves are called
atrioventricular
(AV) valves, meaning
they are located between
the atrium and ventricle.
The four valves help maintain the proper blood flow
through the heart.
These valves keep the blood moving, efficiently and
smoothly, and in the right direction.

43. The tricuspid valve is
between the right atrium
and right ventricle.
The bicuspid valve or
mitral valve is located
between the left atrium and
left ventricle.

44. The pulmonary valve
lies between the right
ventricle and the pulmonary
artery, which takes blood to
the lungs.
When the right ventricle
contracts, the pulmonary
valve opens, allowing
blood to flow to the lungs.

45. The aortic valve lies
between the left ventricle
and the aorta.
This valve (aortic valve)
prevents blood from entering the
aorta prematurely.
The aortic valve opens when the
ventricle contract, allowing
blood to move from the heart
and start the journey to the rest
of the body.

46. The heart needs passageway to distribute blood
throughout the body. These passageway are the:
a) Arteries
b) Veins
c) capillaries

47. The arteries carries
blood away from the
heart and generally
transport oxygen-rich
(oxygenated/carbon
dioxide poor) blood
Arteries branch into smaller
branches called
arterioles before further
branching out to the tiniest
blood vessels called
capillaries.

49. Capillaries connect arteries
and veins.
This is where the gas
exchange between the blood
and the tissues takes place.
Capillaries then merge
into venules then
into larger channels
called veins.
Veins carry blood to the heart and generally transport
oxygen-poor, carbon dioxide rich blood.

51. The Blood
A very vital red fluid (blood) that flows through our blood
vessels, provide oxygen and nourishment to our body
cells
This red fluid (blood) also take away carbon dioxide and
waste product from our body cells.
It also helps maintain body temperature and controls pH.
Blood is transported to the different parts of our body by
the circulatory system.

52. Blood is composed mainly of:
a) Plasma - the yellowish liquid that is composed
of 90% water that carries nutrients, hormones,
and other important substances.b) Different blood cells:
1. red blood cells
2. white blood cells
3. platelets

53. The Red Blood Cells (RBC)
The red blood cells, also
known as
erythrocytes, carry
oxygen to the cells.
After transporting oxygen to the cells, red blood cells
collect the waste gas (carbon dioxide, the by-product of
cellular respiration) and transport it back to the lungs,
where carbon dioxide is expelled from the body as we
exhale.
The red blood cells are the most abundant od the blood
cells (around 5,000,000 red blood cells in drop of blood)
and its lifespan is 120 days.

54. The red blood cells are red in color because they contain
hemoglobin.
Hemoglobin contains
iron (Fe) making it
an excellent
transporter of oxygen
and carbon dioxide.
The long bones of your
body, the spleen, and
the liver continually
produce new red blood
cells to replace old
worn-out cells.

55. The White Blood Cells (WBC)
The white blood cells, also
known as leukocytes,
battle infection, attack and
destroy germs or foreign
proteins that enter the body.
There are about 7,000 WBCs per milliliter of blood (mL)
and this number can be used as an indicator of a disease.
During infection, the body produces more white blood
cells to help fight off the infection.
Still, even during an increased production of white blood
cells, it cannot outnumber the red blood cells.

56. Several types of white blood cells:
a) Neutrophil
combats bacterial and fungal infection
b) Eosinophil
defends against parasitic infections
c) Lymphocytes
B-cells make antibodies to fight the foreign protein
and T-cells function in immune response.
d) Monocytes
remove dead cells debris and clean up the “crime
scene” where the body’s soldiers battle an infection.
e) Basophil
functions during allergic and antigen (foreign
protein
reactions.

58. Platelets
Platelets, also known as
thrombocytes, help the
blood clot, thereby
preventing bleeding when an
artery or vein is severed or
broken.From where the blood is leaking from, the platelets will
stick to the opening of the blood vessels, attracting more
platelets and other blood cells to form a plug that will seal
off the break. Blood clotting is a temporary solution to
stop bleeding.
The lifespan of a platelet is from five to nine days only.
A normal platelet count of a healthy individual is from
150,000 to 450,000 per milliliter of blood.

59. Plasma
Blood plasma is the pale, yellow fluid where the blood cells are
suspended.
Plasma makes up more than half of the total blood volume, roughly
55%.
It consists mainly of water and also contains dissolved constituents
including proteins (such as Albumin, Fibrinogen, and globulins)
glucose, clotting factors, electrolytes, and hormones.
Plasma also contains carbon dioxide because it is the main medium
for elimination of waste products from our body cells.
Plasma also plays a very important role in osmosis, thereby
promoting the balance of electrolytes
Blood serum is blood without the blood cells and the clotting
factors

62. Assignment
1. Name the important constituents of the blood.
2. Give the roles of the following:
a) red blood cells b) white blood cells
c) platelets d) capillaries
e) artery f) vein
g) heart h) venule
i) arteriole
3. Why do arteries possess thicker muscular walls
compared to veins?
4. Even with little pressure flowing through the veins,
how does blood return to the heart?
5. Differentiate blood plasma from blood serum

63. Human Circulatory Paths
The circulatory system has two distinct paths, the
pulmonary circuit and the systemic circuit.
Although they are two distinct path, they actually
occur simultaneously and not in a sequential
manner. Both side of the heart work together.
As the blood leaves for the pulmonary circuit,
some of the blood move through the systemic
circuit.

64. Human Circulatory Paths
Pulmonary circulation can be summed up as the
part of the circulation that carries oxygen-poor blood to
the lungs and bring back oxygen-rich blood to the heart.
Blood enters the
pulmonary circuit
when the right atrium
receives oxygen-poor
(carbon dioxide-rich)
blood from body
tissues through the
superior vena cava
and the inferior vena
cava.

65. The superior vena
cava receives blood
from the upper part
of the body, and the
inferior vena cava
receives blood from
the lower part of the
body.

66. The blood passes through the tricuspid valve into the right
ventricle.
From the right ventricle, the dioxygenated blood is
pumped out from the heart through the pulmonary tract
that splits into the right and left pulmonary arteries going
to the lungs for oxygenation.

67. Carbon dioxide in the blood diffuses into the lungs to pick up fresh
load of oxygen.
At this point, blood is now oxygen-rich (carbon dioxide-poor).
From the lungs, the blood returns to the heart by way of the right
and left pulmonary veins.
Pulmonary circulation end when oxygenated blood returns to the heart.

68. Systemic
circulation is the
movement of
oxygenated blood
from the heart for
distribution
throughout the
body and bringing
in of
dioxygenated
blood to the heart.
Systemic Circulation

69. Oxygenated blood
enters the left atrium,
then the blood passes
through the mitral or
bicuspid valve and into
the left ventricle.
With the great pressure,
the oxygenated blood
from the left ventricle
is pumped into the
aorta, the biggest artery
in the body, to be
distributed throughout
the body via a network
of blood vessels.

70. The aorta branches into smaller arteries, then into
arterioles and finally into capillaries.
Waste and carbon dioxide diffuses out of the cells and into
the blood, the oxygen diffuses out of the blood and into
the cells.
The blood is now carbon dioxide-rich and oxygen-poor.
This dioxygenated blood then continues its travel and the
capillaries merge into venules then to larger veins and
finally into the superior and inferior vena cavas that
drain into the right atrium of the heart.

72. Assignment
1. Compare and contrast the following
a) tricuspid and bicuspid
b) pulmonary and aortic valves
c) pulmonary and systemic circulation
2. Diagram the flow of blood as it enters the right
atrium and leaves the left ventricles for distribution
throughout the body.
3. What causes the pulse?
4. Why does blood spurt out profusely if the blood
vessel on the wrist is cut?

73. STRUCTURE and FUNCTION: Working
Together of the Different Organ Systems
The circulatory system supplies food nutrients and
oxygen that all the cells of a living body needs.
In turn, it collects the metabolic wastes that body cells
produce.
Such dual function of the circulatory system requires a
systematic coordination with other organ system.
To carry out its vital functions, it is imperative for the
circulatory system to reach out to all organs of the body,

74. The Circulatory System and Digestive
SystemMost of the digested foods are absorbed in the
intestinal villi.
Intestinal villi is
the tiny fingerlike
projections at the
lower portion of
the small intestine.
Each villus is
provided with two
kinds of vessels:
capillaries and
lacteals.

75. Molecules of simple sugars and amino acids diffuse into
the capillaries and reach the blood.
Molecules of fatty acids and glycerol diffuse into the
lacteals and reach the lymph. At this point, the circulatory
system takes over.
The circulatory fluids, blood and lymph, distribute the
digested foods to all cells of the body

77. The Circulatory System and the Excretory
System
The circulatory system plays a very important role in the
excretion of metabolic waste products for our body.
The circulating blood is responsible for collecting these
waste products from all body cells and transporting them
to various excretory organs through which particular
wastes are expelled from the body.
How does the circulatory system work with the
kidneys, our body’s major excretory organs?

78. The renal artery brings blood with many impurities
to the kidney.
In the kidney, the
renal artery
subdivides into
small arterioles
that branch into a
network of tiny
capillaries making
up the
glomerulus ,
which is enclosed by
the Bowman’s
capsule.

79. As blood passes through the glomerulus, urine, water,
glucose, and salt are filtered into the Bowman’s capsule.
However, when the
blood passes through
the long convoluted
tubules of the
nephron, much of
the water absorbed
through the glomeruli is
reabsorbed together
with the salts, blood
sugar, blood proteins
and other substances
needed by the body.

80. The liquid which remains
in the tubules is now
called urine.
This excretory waste is
passed on from the
kidney to the ureter
and to the urinary
bladder for temporary
storage.
As urine fills up the urinary bladder, it becomes heavier and
heavier until the sphincter muscle that closes the
opening of the bladder relaxes and the smooth muscles of the
bladder contracts, expelling the urine through the urethra
and out of the body.

81. How does the circulatory system work
with other excretory organs?
The liver cells change amino acids, through the series
of chemical reactions, into urea.
Urea, the nitrogenous
waste is then
transported by the
blood from the liver
mostly to the kidney
where it is filtered out
of the blood and
expelled as part of the
urine.

82. The liver also breaks down old blood cells.
Most of the iron
salts from the blood
cells are brought
back to the bone
marrow by the
blood.
The rest of the
broken blood cells
become part of the
bile which helps in
fat digestion.

83. Urea is also transported by the blood from the liver to the
sweat glands of the skin where it is expelled as part of
sweat, another excretory waste.

84. The Circulatory System and the Nervous
System
The nervous system works with the circulatory system
mainly in the heart by controlling the flow of blood in the
different chambers of the heart.
The nervous system
controls the “electrical
relay system” in the
heart by opening or
closing chambers of the
heart to ensure that blood
travels out of the left
ventricles into the rest of

85. The muscle of the heart and that of the blood vessels are
called involuntary muscle because they are not
under the control of our will.
Their action are governed by the autonomous nervous
system through the sympathetic and
parasympathetic nerves whose actions are
opposite each other.
A sympathetic nerve makes the heart beat faster while a
parasympathetic nerve slows down heart beat.
Thus, the sympathetic and the parasympathetic nerves
regulate and control each other’s activity to maintain
homeostasis or the dynamic balance in the
functioning of the heart.

86. The hypothalamus of the forebrain in the central nervous
system plays another important role for homeostasis .
Among its vital
functions are to
regulate blood
pressure and to
control the
secretions of many
hormones.

87. The Circulatory System and the
Endocrine System
Certain glands in the body release their secretions directly
into the bloodstream instead of through tiny tubelike duct.
These tiny tubelike duct are called ductless or
endocrine glands.
Their secretions are called hormones, are special
protein substances that are present in small quantities in
the body.
They bring about changes in cells or tissues which are
referred to as their “targets”

88. The effect of a hormone may be an increased activity or a
decrease activity of the target cells.
It may also be just plain maintenance of the cells.
Following are some examples of hormone actions
involving the circulatory system.
1. Adrenalin (adrenal gland hormone) increases
blood pressure and heart rate and dilate blood
vessels.
2. Insulin (a pancreatic hormone) lowers blood
sugar level.
3. Parathyroid hormones raises blood calcium level.

89. The Circulatory System and Some Other
Organ System
The circulatory system depends on the skeletal
system for the production of blood cells.
The red blood cells are
produced in the red marrow of
flat bones (such as the ribs)
and long bones (such as thigh
bones)
Blood cells, including red
blood cells, certain white blood
cells and blood platelets are
formed from special connective
tissues referred to as
hemocytoblasts.

90. The circulatory system and the muscular system keep
each other healthy.
The healthier and more active the muscular system is, the
healthier the circulatory system.
Active muscles demand a greater amount of oxygen and
nutrients for energy source and repair of worn-out tissues.
The heart pumps harder to enable the blood to provide
these needs.
Blood also collects waste products from the hardworking
muscles and carries them to their respective excretory
organs.

91. If the circulatory system fails to supply the necessary
requirements, the muscles will cramp and eventually
become dysfunctional.
Long-term inactivity of the muscles is detrimental to the
overall health of the cardiovascular system.
The heart will weaken and lose mass while the blood
vessels serving the muscles will atrophy or shrink along
with the muscles themselves.
On the other hand, enough and regular exercise increases
the mass of body muscles over time.
The heart muscle strengthen and the size of the blood
vessels connected to the active body muscles increases as
well.

92. Assignment
Prepare a summary of how the circulatory system works
together with the different organs of the body. Fill up the
table below:
Organs involved Function related to the circulatory system
Lungs Exchange of gases, blood takes in oxygen and
give off carbon dioxide in the capillaries
around the alveoli or air sac.
1. Small intestine
2. Kidney
3. Liver
4. Skin
5. Brain
6. muscles
7. Bones

93. Use each term in a sentence:
1. Adrenalin
2. Bone marrow
3. Homeostasis
4. Insulin
5. Lymphocytes
6. Hormone
7. Nephron
8. Alveoli
9. Bile
10.liver

94. Conditions Affecting the Respiratory
SystemBronchial asthma
There is a widespread constriction of the bronchial
airways resulting to difficulty in breathing.
This may also be accompanied by cough and wheezing
Bronchial asthma mostly from allergens like pollens,
dust, foods, certain medicines, and bacteria, but may
also be triggered by exertion
-Aerosol spray with bronchodilators
-Nebulizer, in more severe cases
-Administration of oral corticosteroid, if other measures
prove to be ineffective

95. Bronchitis
In a acute bronchitis patient cough out mucopurulent
sptum. Mucopurulent refers to a discharge that contains
mucos and pus
Bronchitis may be viral or bacterial in nature.
Bronchitis associated with cigarette smoking,
emphysema and air pollution.
Bronchitis may be relieved by bronchodilators.

96. Pneumonia
It is the inflammation of the lungs due to infection.
The air sacs become filled with liquid and pus, causing
hardening of the lungs, thus making it difficult for the
lungs to transfer oxygen to the blood. Pneumonia is
always accompanied by cough and high fever.
The infection may be bacterial or viral in nature.
Pneumonia may also be caused by inhalation of
substances that can irritate the lungs, such as chemicals
and liquids.
An appropriate dosage of antibiotics is given at the onset
of pneumonia.

97. Common Cold
The common cold is an example of an upper respiratory
tract infection.
It is a viral infection affecting the nose and throat.
It is characterized by cough, runny nose, watery eyes,
nasal congestion or stuffy nose, sneezing, headache, and
sore throat.
Common colds is caused by more than 200 types of cold
viruses.
We get immune every cold virus we catch but
unfortunately, we can encounter all the different types of
cold virus in our lifetime.

98. There is no known cure except for relieving the
symptoms: analgesic (for pain) decongestant (for stuffy
nose); paracetamol (for fever)
Rest and plenty of fluids like water and juices are
recommended.

99. Lung Cancer
Lung cancer is the result of abnormal cell division
producing abnormal growths.
Symptoms of lung cancer include persistent cough that
worsen over time, chest pain, shortness of breath, blood
in the septum, sudden weight loss, and fatigue
Cigarette smoking is the number one risk factor.
Exposure to second-hand smoke may also cause lung
cancer.
Lung cancer may also caused by job-related exposure to
carcinogens like asbestos.
A cancer gene is another predisposing factor that may be
aggravated by one’s lifestyle.

100. Lung cancer if caught early, requires surgery of the lung
lobe containing the tumor, combined with chemotherapy.
Chemotherapy and
Radiation therapy do not result in the cure of lung
cancer, but rather help in prolonging the patient’s life.

101. This is a progressive condition of an abnormal build up
of air in the alveolar sacs causing their enlargement and
damage
Enlargement of alveolar sac causes loss of elasticity,
reduction of surface area for gas exchange and decreased
lung capacity, resulting in less take up of oxygen.
Cigarette smoking is the primary cause.
Age: older individuals are more susceptible to this
disease.
Emphysema

102. Relieving symptoms that include shortness of breath,
coughing, and wheezing.
Bronchodilators open the airways.

103. This refers to the inflammation of the mucous lining of
the nose, characterized by cold-like symptoms such as
sneezing, runny nose, watery eyes, and itchiness.
Nasal polyps, the fleshy growths inside the nasal cavity,
can result in having allergic rhinitis.
Rhinits
This may be viral (in acute rhinitis)
This may also be an allergic reaction to tree or grass
pollens, dust, animal danders, etc. (in allergic rhinitis)

104. Although not harmful, rhinitis is very irritating.
Avoiding allergens for the other cold-like symptoms, a
non-sedative antihistamine and decongestant may be
taken.

105. Tuberculosis (TB) is an infection characterized by the
formation of nodules in the tissues.
Its primary location is the lungs, but may occur in other
parts of the body such as the larynx, brain, joints, etc.
TB in the lungs manifests these symptoms.
-Persistent coughing
-Deep pain on the chest when breathing in and out
-Coughing out blood
-Weakness
-Fever, which can be low grade
Tuberculosis

106. This an airborne disease, that spreads from person-to-
person through the air, and inhaled into the lungs
This is caused by Mycobacterium tuberculosis.
This may cause death if not treated early and properly.
It can be treated by the correct combination of
antibiotics.
This may be prevented by the BCG vaccine, a live
bacterial vaccine, usually given to children.

107. Cystic fibrosis (CF)
CF is a lifelong disease and is an inherited disorder
affecting the epithelial cells.
Normally, epithelial cells produce mucus and other
watery secretions.
In a person with CF, the epithelial cells produce mucus
that is much thicker than normal, causing entrapment of
germs and repeated lung infection.

108. A CF gene inherited from each parent will manifest
symptoms of CF on the offspring.
If only one CF gene was inherited, no symptoms will
manifest, but the person will be a carrier of the gene.
There is no known cure, nor preventive measures.
Patients are given vitamin supplements and pancreatic
enzymes
Antibiotics are given if repeated lung infections occur.
This is usually fatal