Science Objective Questions and Answers: Chapter 13 Why Do We Fall Ill
Access targeted multiple-choice questions for Chapter 13 Why Do We Fall Ill designed to align with the latest CBSE academic syllabus for Class 9 Science. These objective practice sets help students evaluate their conceptual understanding and improve exam readiness.
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Question: Which of the following medicine is used to reduce the inflammatory reactions?
a) Analgesics
b) Antipyretics
c) Antihistamines
d) Antibiotics
Answer: c
Question: BCG is an effective vaccine to prevent
a) tetanus
b) tuberculosis
c) diphtheria
d) pertussis.
Answer: b
Question: Given below are the pairs of disease and casual pathogen. Which one of the these is not a matching pair?
a) Kala azar – Leishmania
b) Sleeping sickness – Trypanosoma
c) Malaria – Salmonella
d) Chicken pox – Varicella
Answer: c
Question: Full form of DPT is
a) Dengue Pneumonia Typhoid
b) Diphtheria Pertussis Tetanus
c) Diphtheria Pertussis Typhoid
d) Dengue Pneumonia Tetanus.
Answer: b
Question: Which of the following is correct regarding penicillin?
a) It interferes in the biological pathway of bacteria.
b) It is an antibiotic that can kill bacteria.
c) Penicillin is obtained from a fungus.
d) all of the options
Answer: d
Question: Vaccination
a) develops resistance against the attack of a pathogen.
b) can control every disease
c) kills all the disease causing organisms in the area
d) involves the use of antibodies.
Answer: a
Question: Community health programme includes all of the options, except
a) providing health education
b) providing safe disposal of sewage
c) providing clean drinking water
d) providing only packaged food.
Answer: d
Question: The limitations that are normally confronted while treating an infectious disease is/are
a) body functions are impaired and may never recover completely
b) the patient is confined to bed for some time
c) infected person serves as a potential source of spread of infectious disease to other persons
d) all of the options.
Answer: d
Question: Which of the following correctly exemplifies acquisition of active immunity by a person?
a) A person who has recovered from an attack of mumps, develops natural active immunity.
b) When ready-made antibodies are directly injected into a person’s body to protect him against foreign agents, then he acquires artificial active immunity.
c) When a person is vaccinated for a disease then he acquires natural active immunity for that disease.
d) When antibody is transferred from mother to the fetus through placenta then the developing baby acquires artificial active immunity.
Answer: a
Question: Health can be best defined as a state of
a) being physically healthy
b) not being diseased
c) being physically healthy and disease-free
d) being well enough to function well physically, mentally and socially.
Answer: d
Question: In case of snake bite, the doctor treats the patient with preformed antibodies. What type of immunity will be developed?
a) Artificial passive acquired immunity
b) Naturally active acquired immunity
c) Artificial active acquired immunity
d) Naturally passive acquired immunity
Answer: a
Question: The given figure shows an organism responsible for causing the disease. Identify the disease.

a) Kala-azar
b) Elephantiasis
c) Sleeping sickness
d) AIDS image
Answer: c
Question: Which of the following diseases is caused due to Helicobacter pylori ?
a) Tuberculosis
b) Peptic ulcer
c) Cancer
d) Elephantiasis
Answer: c
Question: Severity of disease symptoms depends upon
a) number of microbes
b) target organ
c) both number of microbes and target organ
d) none of the options.
Answer: c
Question: Which type of diseases affect the body suddenly but, last for a short time?
a) Acute disease
b) Chronic disease
c) Congenital disease
d) Genetic disorder
Answer: a
Question: The disease which occurs due to deficiency of vitamin C is
a) goitre
b) beri-beri
c) scurvy
d) cheilosis.
Answer: c
Question: Select the correct statements.
(i) Food is the basic necessity for cell and tissue functions.
(ii) Mental well being is the basic necessity for proper functioning of cells and tissues.
(iii) Anything that prevents proper functioning of cells and tissues will lead to a lack of proper activity of the body.
a) (i) and (iii)
b) (i) and (ii)
c) (ii) and (iii)
d) (i), (ii) and (iii)
Answer: a
Question: Match column I with column II and select the correct option from given codes.
Column I Column II
P. TB 1. Intestine
Q. Hepatitis 2. Lungs
R. Cholera 3. Brain
S. Influenza 4. Liver
T. Fits 5. Nasal chambers
a) P-3, Q-1, R-5, S-2, T-4
b) P-4, Q-2, R-5, S-1, T-3
c) P-2, Q-4, R-1, S-5, T-3
d) P-3, Q-1, R-4, S-2, T-5
Answer: c
Question: Match the disease in column I with the appropriate items (pathogen/prevention/treatment) in column II.
Column I Column II
a) Amoebiasis (i) Treponema pallidum
b) Diphtheria (ii) Use only sterilised food and water
c) Cholera (iii) DPT vaccine
d) Syphilis (iv) Use oral hydration therapy
a) A–(i), B–(iii), C–(ii), D–(iv)
b) A–(ii), B–(iii), C–(iv), D–(i)
c) A–(i), B–(ii), C–(iii), D–(iv)
d) A–(ii), B–(iv), C–(i), D–(iii)
Answer: b
Question: Fill in the blanks and select the correct option.
Diseases that last only for very short periods of time are called
(i) diseases. For example,
(ii) lasts only for a few days. On the other hand, ailments that last for a long time, even as long as a lifetime are called
(iii) diseases. For example
(iv) , which is very common in some parts of India.
(i) (ii) (iii) (iv)
a) Acute Diabetes Chronic Arthritis
b) Chronic Common cold Acute Tuberculosis
c) Acute Common cold Chronic Elephantiasis
d) Chronic Cancer Acute Cough
Answer: c
Question: Which of the following statements is/are correct about individual health?
(i) Public cleanliness is important for individual health.
(ii) Social environment is also important for individual health.
(iii) Physical environment is decided by our social environment.
(iv) Good economic conditions and jobs are needed for individual health.
a) Only (i)
b) (ii) and (iv)
c) Only (iii)
d) (i), (ii), (iii) and (iv)
Answer: d
Case Based Mcqs
Sukriti and Priya are good friends and study in class 1 of a reputed school. On a hot summer day, while they both were playing in the school playground, Priya felt uncomfortable and sat down. After some time she developed acute headache and high fever. Her legs stopped moving and she also felt some stiffness in her neck. Soon she became unconscious.
Question: What could be the probable reason for Sukriti not being affected by pathogen of this disease?
a) Sukriti’s immune system has already encountered the weakened pathogens and developed memory cells, which produce antibodies whenever pathogen enters her body.
b) Sukriti had actually contracted the disease few months back and recovered, hence her immune system has developed memory cells,which prevent any subsequent pathogen attack.
c) Sukriti is taking antibiotics regularly, which kill the pathogens entering her body and prevent the actual disease.
d) Sukriti has received antibodies against the pathogen from her mother via placenta so she is immune to the pathogen of this disease by birth.
Answer: a
Question: Identify the disease which Priya has contracted, along with its causative agent and mode of transmission.
Disease Causative Mode of agent transmission
a) Malaria Protozoan Bite of infected Anopheles
b) Tuberculosis Bacteria Contaminated water
c) Polio Virus Faecal oral route
d) Diphtheria Fungus Sharing of clothes
Answer: c
Question: Which of the following is the most widely used vaccine for the prevention of disease contracted to Priya?
a) OPV
b) MMR
c) DPT
d) BCG
Answer: a
X and Y are communicable diseases where X can spread from an infected person to a healthy person by direct contact between them whereas Y can spread from an infected person to healthy person through some intermediate agents.
Question: Which one of the following is an example of ‘X’?
a) Filariasis
b) Leprosy
c) Cholera
d) Typhoid
Answer: b
Question: Which of the following pathogen cannot be responsible for causing X?
a) Streptococcus pneumoniae
b) Ascaris lumbricoides
c) Plasmodium vivax
d) all of the options.
Answer: d
Question: Which of the following is an example of disease ‘Y’?
a) Pneumonia
b) Marasmus
c) Pellagra
d) Goitre
Answer: a
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Multiple Choice Questions (MCQs) for Class 9 Science Chapter 13 Why Do We Fall Ill
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FAQs
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