Extra Questions: Class 8 Science Chapter 3 Health The Ultimate Treasure

Practice questions beyond the textbook exercise, testing deeper understanding of health, disease and immunity for Class 8 Science Chapter 3: Health: The Ultimate Treasure. These Class 8 Science Chapter 3 important questions are handy for last-minute exam practice.

Last Updated: September 23, 2026

Extra Questions: Class 8 Science Chapter 3 Health The Ultimate Treasure

1. 1 (Assertion-Reason). Assertion: Vaccines prevent disease without causing the illness itself. Reason: Vaccines train the immune system using a weakened, dead, or partial form of the pathogen.
   Solution: Both true, and the reason correctly explains the assertion.
2. 2 (Short Answer). Name two diseases spread by mosquitoes.
   Solution: Malaria and Dengue (Chikungunya is also acceptable).
3. 3 (Applied). A student takes antibiotics every time they get a cold. Explain why this is a harmful habit.
   Solution: Colds are viral, so antibiotics have no effect on them; repeated unnecessary use promotes antibiotic resistance, making bacteria harder to treat in future genuine bacterial infections.
4. 4 (Assertion-Reason). Assertion: Handwashing reduces the spread of communicable diseases. Reason: Many pathogens spread through contact with contaminated hands and surfaces.
   Solution: Both true, and the reason correctly explains the assertion.
5. 5 (Synthesis). Explain, using the idea of memory cells, why chickenpox usually only infects a person once in their lifetime.
   Solution: After the first infection, the immune system retains memory B- and T-cells specific to the chickenpox virus; on future exposure these cells respond immediately and strongly, clearing the virus before it can cause illness again.
6. 6 (Short Answer). Give one example each of a water-borne and an airborne communicable disease.
   Solution: Water-borne: Cholera (or Typhoid/Hepatitis A). Airborne: Tuberculosis (or Flu/Measles).
7. 7 (Applied). A locality has poor sanitation and frequent waterlogging. Predict two communicable diseases likely to rise there, and explain why.
   Solution: Cholera/Typhoid (contaminated water from poor sanitation) and Dengue/Malaria (waterlogging creates mosquito breeding grounds).
8. 8 (Assertion-Reason). Assertion: Stress can make a person more likely to fall sick. Reason: Chronic stress suppresses immune function.
   Solution: Both true, and the reason correctly explains the assertion.
9. 9 (Short Answer). What is the WHO definition of health?
   Solution: A state of complete physical, mental and social well-being — not merely the absence of disease.
10. 10 (Applied). Why do doctors recommend completing the full course of antibiotics even after symptoms disappear?
    Solution: Stopping early can leave some bacteria alive, which may develop resistance to the antibiotic, making the infection harder to treat if it recurs.

Frequently Asked Questions

Why are vaccines effective in preventing certain diseases before they even occur?
Vaccines introduce a weakened or inactive form of a pathogen into the body, prompting the immune system to develop antibodies, so the body is prepared to fight off the actual disease if exposed to it later.

What lifestyle habits are commonly recommended to prevent non-communicable diseases?
Regular physical activity, a balanced diet low in excessive salt, sugar, and unhealthy fats, adequate sleep, and avoiding tobacco and alcohol are commonly recommended habits that reduce risk over time.

Written by Satish

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