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Class 8 Science: Health, The Ultimate Treasure, 8 practice questions with answers

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These are 8 practice questions on Class 8 Science Chapter 3, Health: The Ultimate Treasure, of the new NCERT textbook, Curiosity. Each has a worked answer and the textbook page it comes from. They cover the three sides of health, symptoms and signs, how communicable diseases spread and what vectors are, non-communicable and deficiency diseases, what vaccines can and cannot do, and why antibiotics must be used as a doctor prescribes. Try each one before you open the answer.

These questions are our own, drafted with AI help, and every answer was checked against the textbook page it cites, but no practising teacher has reviewed them yet. If you find a mistake, please tell us. This page explains the textbook; it is not medical advice. If you feel unwell, tell a parent, a teacher or another adult, who can check with a doctor.

What the chapter says you need

Facts from the NCERT textbook (Curiosity: Textbook of Science for Grade 8, Chapter 3, printed pages 28 to 45):

What health means, and how we know we are unwell

Question 1. Match each habit to the side of health it mainly supports (physical, mental or social): (a) a long walk every morning, (b) telling a friend when something is worrying you, (c) helping neighbours plant trees in the colony park.

Answer: (a) physical; (b) mental; (c) social. Health is complete physical, mental and social well-being. A daily walk keeps the body fit (physical). Sharing a worry instead of keeping it in helps your mind (mental). Working together with neighbours builds relationships (social), and being outdoors and active helps the body too. (The three aspects of health, page 29; staying active and spending time with others, pages 30 and 31.)

Question 2. Riya has a headache and a red rash on her arm. She says, "The headache is a sign and the rash is a symptom." Find her mistake.

Answer: she has them the wrong way round. A symptom is what a person feels, like pain, so the headache is a symptom. A sign is something that can be seen or measured, so the rash is a sign. Both help a doctor understand what might be making someone unwell. (Symptoms and signs, page 31.)

Diseases: causes and types

Question 3. Neel says, "Mosquitoes cause malaria." Find his mistake.

Answer: malaria is caused by a protozoan; the mosquito only spreads it. Malaria is a communicable disease caused by protozoa, single-celled organisms. The mosquito carries the pathogen from one person to another, so it is a vector, not the cause. (Pathogens and vectors, pages 32 and 33; malaria, page 35.)

Question 4. Tara's grandfather has diabetes. Tara is afraid to sit next to him because she might "catch" it. Explain why she does not need to worry about that.

Answer: diabetes is a non-communicable disease, so it does not spread from person to person. Non-communicable diseases such as diabetes, cancer and asthma are not caused by pathogens and do not spread from one person to another; they are linked to lifestyle, diet and the environment, along with other causes such as hormonal imbalances. Sitting next to her grandfather cannot pass diabetes to Tara. (Non-communicable diseases, page 32; diabetes, page 36.)

Question 5. Meena reads that scurvy is caused by a lack of a certain nutrient. Her friend says, "Then stay away from anyone with scurvy, or you will catch it." Is the friend right?

Answer: no; scurvy is a deficiency disease, and deficiency diseases are non-communicable. Scurvy, anaemia and goitre are caused by a lack of specific nutrients in the diet, not by pathogens. Diseases like these are called deficiency diseases, and they do not spread from one person to another. (Deficiency diseases, pages 35 and 36.)

Prevention and treatment

Question 6. Ravi's doctor prescribed an antibiotic for a bacterial infection. After two days he feels better, so he stops taking it and keeps the rest of the tablets to take by himself the next time he feels ill. What is wrong with this plan?

Answer: he stopped before finishing the prescribed dose, and he plans to take an antibiotic without a doctor's prescription. The book says antibiotics should be used only when prescribed by a doctor, in the correct dose and for the right duration. Taking an incomplete dose, or taking antibiotics when they are not needed, helps bacteria become resistant to them, and resistant bacteria make infections harder to treat. Ravi should ask his doctor or another adult before stopping a medicine, and should not take leftover antibiotics on his own. (Antibiotics, page 39; antibiotic resistance and its prevention, pages 40 and 41.)

Question 7. Sam says, "If I get measles, I will just take the measles vaccine and it will cure me." Find his mistake.

Answer: vaccines prevent diseases; they do not cure them. A vaccine trains the immune system to recognise and attack a germ before an infection happens. Vaccines are preventive, not curative: they help stop serious diseases before they happen but do not treat someone who is already sick. That is why vaccines are given in advance, often in childhood. (Vaccines, pages 37 and 39.)

Question 8. Which route of spreading disease does each habit block: (a) covering the mouth and nose when sneezing, (b) not sharing towels, (c) emptying water that collects in old tyres and pots, (d) drinking boiled water?

Answer: (a) the air; (b) indirect contact; (c) vectors (mosquitoes); (d) contaminated water. A sneeze sends pathogens into the air, so covering the mouth and nose blocks spread through the air. Sharing personal items such as towels spreads pathogens by indirect contact. The book's prevention for malaria and dengue includes controlling mosquito breeding around the home and avoiding areas with still water, so emptying still water cuts down the vectors. Boiling drinking water protects against diseases that spread through contaminated water. (Ways diseases spread, pages 32 and 33; preventive measures in Table 3.1, pages 33 to 35.)

Questions students ask

What is the difference between communicable and non-communicable diseases? Communicable diseases are caused by pathogens and can spread from one person to another, like flu or typhoid. Non-communicable diseases, like diabetes or asthma, are not caused by pathogens and do not spread from person to person. (Page 32.)

What is immunity? The natural ability of our body to fight diseases, through the immune system. Protection that develops after exposure to a pathogen or a vaccine is called acquired immunity. (Page 37.)

What is antibiotic resistance? It is when bacteria that a given antibiotic used to kill survive and multiply despite treatment with it, which makes infections harder to treat. Using antibiotics only as prescribed helps prevent it. (Pages 40 and 41.)

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Sources

All opened and read on 22 October 2026. Page numbers are the printed page numbers of the textbook; printed page = PDF page + 27.

The facts are from the textbook pages above. The questions and worked answers are our own. This guide is general information, not medical advice; follow your teacher, the textbook and your doctor.