Free Why Do We Fall Ill? 01 Practice Test - 9th Grade 

Question 1

AIDS cannot be transmitted from an infected person to a healthy person by ________ .

A. blood transfusion
B. shaking hands
C. sexual contact
D. infected needles


Solution : B

HIV spread only through body fluids of an infected person. These fluids are blood, semen, pre-seminal fluids, rectal fluids, vaginal fluids and breast milk.

Question 2

Which of the following are communicable diseases?










Solution : B and D

Infectious diseases are caused by certain microorganisms called pathogens and leads to infections. These can be spread from one person to another and hence they are also called communicable diseases.  Diphtheria is an infectious disease spread by direct physical contact or breathing the aerosolized secretions of infected individuals. Kala-azar can be spread from person to person by the bite of an infected sandfly.

Question 3

A disease that lasts for a short period of time is called an acute disease.

A. True
B. False


Solution : A

Some diseases persist for only a very short period, and these are called acute diseases. E.g. common cold, appendicitis, etc. Symptoms of other diseases prolong for several years or even a lifetime. These are called chronic diseases. E.g. elephantiasis, AIDS, etc.  

Question 4

Air-borne diseases are most likely to affect the ______ .

A. gut
B. lungs
C. liver
D. skin


Solution : B

Microbes in the air enters into a person while breathing. The microbes are taken into the lungs, which is the primary place of infection. The examples of air-borne diseases are common cold, pneumonia and tuberculosis.

Question 5

Which one of these is a chronic disease?

A. Tetanus
B. Diphtheria
C. Influenza
D. Cancer


Solution : D

Chronic diseases are those diseases which last for a long period of time and weaken the body by attacking the immune system. Cancer is an example of chronic disease. A cancer patient may suffer for many years to a lifetime in worse conditions. 

Question 6

The first vaccine was discovered by Edward Jenner. The target disease was ___.

A. Small pox
B. Chicken pox
D. Measles 


Solution : A

Edward Jenner discovered the vaccine for smallpox in 1798. Working in an agricultural community, Jenner knew that milkmaids never caught smallpox. However, they inevitably caught cowpox. Jenner speculated that exposure to cowpox produced immunity against smallpox and even encountered locals who claimed to have deliberately infected themselves to provoke such a response. Jenner injected an eight-year-old boy with pus from cowpox blisters on the hands of a milkmaid and the boy developed immunity against smallpox.

Question 7

Which of the following are viral diseases?

A. Common cold
B. Influenza
C. Cholera
D. Malaria


Solution : A and B

Common examples of diseases caused by virus are common cold, influenza, dengue fever etc. Cholera is caused by bacteria and malaria is caused by protozoan microbes.

Question 8

Tuberculosis is an example of water-borne disease.

A. True
B. False


Solution : B

Tuberculosis is a deadly disease of the respiratory tract. It spreads from an infected person to a healthy person via pathogen-containing tiny air droplets which are released by an infected person while coughing or sneezing.

Question 9

Our body has a special mechanism to fight against infectious pathogens. This property is called immunization.

A. True
B. False


Solution : B

Our body has a special mechanism to fight against infectious pathogens. This property is called immunity. The immune system consists of certain immune cells which produce allergies, reactions or antibodies against antigens (foreign particles) entering our body. The process of resistance against diseases is called immunization.

Question 10

By which of the following ways an infection can be prevented?

A. Vaccination 
B. Sharing personal belongings such as a razor, drinking glass, toothbrush, etc.
C. Wearing a mask while visiting patients in hospitals.
D. Maintaining the proper hand hygiene.


Solution : A, C, and D

Some of the ways in which an infection can be prevented are as follows.
-Maintain personal hygiene.
-Keep kitchen clean by washing utensils, dishes, cooking area before and after preparing food.
-Keep both bathroom and toilet area clean.
-Avoid sharing personal belongings such as a razor, drinking glass, toothbrush, comb, etc.
-Do not travel or go to work when you fall ill.
-While visiting patients in hospitals, it is recommended to wear a mask or gown and if possible make use of sanitizing gels to prevent infection.