MCQ Questions for Class 9 Science Chapter 13 Why Do We Fall Ill with Answers
MCQs from Class 9 Science Chapter 13 – Why Do We Fall Ill are provided here to help students prepare for their upcoming Science exam.
MCQs from CBSE Class 9 Science Chapter 13: Why Do We Fall Ill
Q1. You are aware of Polio Eradication Programme in your city. Children are vaccinated because
(a) Vaccination kills the polio causing microorganisms
(b) Prevents the entry of polio causing organisms in the body
(c)It creates immunity in the body
(d) All of above
Answer/ Explanation
(c) It creates immunity in the body
Q2. Making anti-viral drugs is more difficult than making anti-bacterial medicines because
i. Viruses make use of host machinery
ii. Viruses are on the border line of living and non-living
iii. Viruses have very few biochemical mechanisms of their own
iv. Viruses have a protein coat
Choose the correct option among the following:
(a) (i) and (iii)
(b) only(iii)
(c) (ii) and (iv)
(d) only(iv)
Answer/ Explanation
(b) only (iii)
Q3. Many of the people suffer from the problem of acnes and feel annoyed of the ugly skin texture caused due to the acne spots. Can you guess the microorganism causing these acne?
(a) H1N1 virus
(b) Trypanosoma
(c)Leishmania
(d) Staphylococcus
Answer/ Explanation
(d) Staphylococcus
Q4. If you live in an overcrowded and poorly ventilated house, then you may suffer from which of the following diseases?
i. Cholera
ii. AIDS
iii. Air borne disease
iv. Cancer
Choose the correct option among the following:
(a) (i) and (iii)
(b) (ii) and (iii)
(c) only(iii)
(d) only (iv)
Answer/ Explanation
(c) only (iii)
Q5. Antibiotics are ineffective against the viral infections. For each type of the viral infection, human body produces its own antiviral protein that is released from the infected and dying host cells. What is this protein called?
(a) Interferon
(b) Leishmania
(c) Ascaris
(d) Pertussis
Answer/ Explanation
(a) Interferon
Q6. Cancer is a disease caused due to the uncontrolled growth of tissues in any part of body. This disease comes under which of the following types?
(a) Congenital disease
(b) Infectious disease
(c)Non-infectious disease
(d) None of these
Answer/ Explanation
(c) Non-infectious disease
Q7. The main symptoms of the HIV-AIDS infection are due to the fact that patient’s body can no longer fight off many minor infections and hence becomes the reason of the patient’s ultimate death.
This happens because:
(a) HIV virus alone causes all the infections
(b) HIV virus releases a poison in the body
(c) HIV virus damages the immune system of the body
(d) HIV virus directly attacks the human nervous system
Answer/ Explanation
(c) HIV virus damages the immune system of the body
Q8. Tuberculosis is a disease which spreads from one person to another directly or indirectly is diagnosed with the help of a protein extracted from a bacterium called Mycobacterium tuberculosis which also causes the disease. What is the name of this protein?
(a) Tuberlysis
(b) Rifampicin
(c) Cephalosporin
(d) Tuberculin
Answer/ Explanation
(d) Tuberculin
Q9. Cholera is an infectious, fatal disease caused by the bacterium which lives and multiplies in the small intestine. The disease sometimes occurs in epidemic form. Which of the following is not a reason for the spread of the disease?
(a) Breeding of the flies on the garbage heaps
(b) Use of spices in food
(c)Drinking the contaminated water
(d) Consuming the contaminated food
Answer/ Explanation
(b) Use of spices in food
Q10. For the prevention of the dehydration, the patient is advised to take Oral Rehydration Solution (ORS). The main components of ORS solution are:
(a) Sodium chloride, sodium bicarbonate, potassium chloride, glucose, sucrose and water
(b) Sodium chloride, sodium carbonate, potassium chloride, glucose,sucrose and water
(c)Sodium carbonate, sodium bicarbonate, potassium chloride, glucose,sucrose and water
(d) Sodium chloride, sodium bicarbonate, potassium chloride, glucose,sucrose and water
Answer/ Explanation
(a) Sodium chloride, sodium bicarbonate, potassium chloride, glucose, sucrose and water
Q11. TAB-vaccine is used to provide immunity against Typhoid for a period of three years.What is the correct abbreviation of TAB?
(a) Typhoid-Paratyphoid A and B Vaccine
(b) Typhoid-Partialtyphoid A and B Vaccine
(c)Typhoid-Peroxytyphoid A and B Vaccine
(d) Typhoid-Pertyphoid A and B Vaccine
Answer/ Explanation
(a) Typhoid-Paratyphoid A and B Vaccine
Q12. Water makes averagely about 60% part of human body and is necessary in every biochemical reaction occurring in human body. Which of the following is a disease which is caused due to the loss of water in the body making the patient seriously ill in a very short time?
(a) Rehydration
(b) Hydration
(c)Dehydration
(d) Hydrolysis
Answer/ Explanation
(c) Dehydration
Q13. Which of the following is an incorrect statement about tuberculosis?
i. It is caused by Salmonella
ii. It commonly affects immune system
iii. Bacteria release tuberculin toxin
iv. Patient’s sputum contains blood
Choose the correct option among the following:
(a) (ii) and (iii)
(b) Only (ii)
(c) (iii) and (iv)
(d) (i) and (ii)
Answer/ Explanation
(d) (i) and (ii)
Q14. Mosquitoes are often seen breeding on the stagnant water. We should not allow mosquitoes to breed in our surroundings because they
(a) multiply very fast and cause pollution
(b) are vectors for many diseases
(c) bite and cause skin diseases
(d) are not important insects
Answer/ Explanation
(b) are vectors for many diseases
Q15. Infectious diseases are the diseases that can spread from infected person to the healthy person. Which of the following can make you ill if you come in contact with an infected person?
(a) Genetic abnormality
(b) Blood cancer
(c) High blood pressure
(d) Sneezing and coughing
Answer/ Explanation
(d) Sneezing and coughing