13 marksCuriosity Grade 8, Chapter 3, Discover, design, and debate, page 45
Maintain a health diary for at least a month, tracking food, hygiene, exercise, sleep, screen time and emotional state. How would you set it up and what would you look for?
Hint. Six columns, and the last one is the easiest to skip and the most revealing.
Setting it up. One row per day for at least a month, with a column for each item. Record on the day, not from memory at the end of the week — a point Chapter 1 made about experimental notes and which applies equally here.
| Column | What to record |
|---|
| Food | Meals eaten, whether breakfast was skipped, junk or processed food |
| Hygiene | Hand-washing before meals, bathing, brushing, clean clothes |
| Exercise | Type and roughly how long — walking, cycling, sport, yoga |
| Sleep | Hours slept, and what time you went to bed |
| Screen time | Roughly how many hours, and when (especially late at night) |
| Emotional state | How you felt — cheerful, tired, anxious, low — in a word or two |
What to look for after a month. Not single days, but patterns and connections:
- Do you sleep worse on high screen-time days?
- Does your mood dip on days with little exercise or no time with friends?
- Does skipping breakfast track with feeling tired later?
- Do headaches or tiredness cluster with particular habits?
Why the emotional column matters most. It is the one people leave blank, and it is the one that made the difference in Activity 3.1 — where loneliness, not any germ, produced headaches, weight loss and sleeplessness. A diary with only food and exercise would have missed the actual cause.
Be honest. A diary recording what you meant to do is useless. Its only value is as an accurate record.
✦ Answer: keep a daily record with six columns — food, hygiene, exercise, sleep, screen time and emotional state — filled in on the day, then look for patterns linking habits to how you feel, remembering that the emotional column is the one Activity 3.1 showed to matter most.
24 marksCuriosity Grade 8, Chapter 3, Discover, design, and debate, page 45
Read about Indian scientists like Suniti Solomon, Asima Chatterjee, Yellapragada Subbarao and Mary Poonen Lukose for their contributions in the field of health and diseases.
Hint. This is a reading task — what follows is a starting point to verify and expand, not a substitute for the reading.
How to approach it. For each scientist, find out what problem they worked on, what they contributed, and who benefited. Use your library, your school textbooks and reliable sources, and note where each fact came from — the same discipline the chapter asks for when it says to consult trusted health sources.
Starting points, to be checked and expanded:
| Scientist | Field to read about |
|---|
| Suniti Solomon | HIV/AIDS in India — she was among the first to document HIV infection in the country, and worked on testing, treatment and reducing stigma |
| Asima Chatterjee | Organic chemistry of medicinal plants — her work contributed to drugs for conditions including epilepsy and malaria |
| Yellapragada Subbarao | Biochemistry — his work contributed to important medicines, including in the areas of folic acid and antibiotics |
| Mary Poonen Lukose | One of India's earliest women doctors, and a pioneering figure in public health administration in Travancore |
Questions worth answering for each: What health problem were they facing? What did they have to work out? Did their work reach ordinary patients, and how? What obstacles did they overcome?
A note on how to write this up. Give the specific contribution rather than praise — 'she documented the first HIV cases in India' says something; 'she was a great scientist' does not. And if sources disagree on a date or detail, say so rather than picking one silently.
Connecting to the chapter. Together these four span its whole range: an infectious disease (Solomon), medicines from natural substances (Chatterjee), drug discovery (Subbarao) and public health (Lukose) — the same four fronts on which this chapter says disease is fought.
✦ Answer: research each scientist's specific contribution and who benefited from it — Solomon on HIV/AIDS in India, Chatterjee on medicinal-plant chemistry, Subbarao on biochemistry and drug discovery, Lukose on medicine and public health administration — citing reliable sources and noting any disagreement between them.
34 marksCuriosity Grade 8, Chapter 3, Discover, design, and debate, page 45
Smallpox was eradicated by vaccination. Discover how this was done and why it worked. Debate whether everyone should be required to get vaccinated to protect others.
Hint. The 'why it worked' half has a scientific answer; the debate half has arguments on both sides.
How it was done. Jenner's discovery in the late 1700s gave the first vaccine; the chapter's graph then shows the modern campaign — countries reporting smallpox falling away after the 1965 vaccine campaign, until smallpox was eradicated in 1979. The method was mass vaccination, sustained worldwide until there was nowhere left for the disease to survive.
Why it worked. Several features of smallpox made eradication possible:
- Vaccination gives acquired immunity, so a vaccinated person neither catches the disease nor passes it on — vaccination breaks transmission, not just individual risk
- Smallpox spreads only between people, so removing it from humans removed it entirely
- Its symptoms were visible and distinctive (blisters), so cases could be found and their contacts vaccinated
- The campaign was worldwide and sustained — a disease eliminated in one country returns if it survives in another
The debate — should vaccination be required?
For: vaccination protects others as well as yourself, including babies and ill people who cannot be vaccinated; a disease only disappears if enough people participate, so one person's refusal has consequences beyond themselves; vaccines are carefully tested for safety; and society already requires many things for public safety.
Against: people generally have a right to decide about their own medical treatment; compulsion can increase distrust and resistance rather than reduce it; genuine medical exemptions exist and must be respected; and good information, easy access and free provision may achieve high uptake without force.
How to debate it well. Argue from evidence, not slogans; state what would change your mind; and distinguish should people be vaccinated (on which the science is clear) from should they be compelled (which is a question about rights and public good, where reasonable people disagree).
✦ Answer: smallpox was eradicated by sustained worldwide mass vaccination, which worked because vaccination breaks transmission, the disease spread only between humans, and its visible symptoms allowed cases to be traced; on compulsion, weigh protection of those who cannot be vaccinated against individual medical choice.
43 marksCuriosity Grade 8, Chapter 3, Discover, design, and debate, page 45
Learn the correct sequence of steps for performing cardiopulmonary resuscitation (CPR) on an adult whose breathing has suddenly stopped, according to current guidelines. Your school may invite a doctor or professional to demonstrate a mock drill.
Hint. The chapter's own instruction — 'according to current guidelines', and a demonstration by a professional — is part of the answer.
Read the task carefully first. The chapter says according to current guidelines and suggests inviting a doctor or a professional to demonstrate a mock drill. Both matter. CPR guidelines are revised from time to time, and CPR is a practical skill that cannot be learnt from a written description — it needs hands-on practice on a manikin under a qualified instructor. Treat what follows as an outline of what to learn, then learn it properly from a certified trainer and follow whatever the current guideline says.
The broad sequence that current guidelines teach:
- Check the scene is safe for you before approaching
- Check responsiveness — tap the shoulders and shout
- Call for help immediately — in India the national emergency number is 112 (many states also use 108 for ambulances). Ask a specific person to call, and to fetch an AED if one is available
- Check breathing — look for normal breathing for no more than about 10 seconds; occasional gasping is not normal breathing
- If not breathing normally, begin chest compressions — hard and fast in the centre of the chest, at about 100-120 compressions per minute, allowing the chest to come fully back up between compressions, and interrupting as little as possible
- Give rescue breaths only if you are trained to; otherwise continue compressions alone
- Use an AED as soon as one arrives, following its spoken instructions
- Continue until professional help takes over or the person starts breathing normally
Why speed matters. Every minute without circulation reduces the chance of survival, which is why calling for help and starting compressions come before anything else.
What the mock drill adds. Correct hand position, how hard to press, the rhythm, and swapping with another rescuer when tired — none of which can be judged from a page.
✦ Answer: the sequence is check the scene → check responsiveness → call 112 for help → check breathing → begin chest compressions at 100-120 per minute → rescue breaths only if trained → use an AED when it arrives → continue until help takes over — but learn it hands-on from a qualified instructor and follow the current guideline, since CPR is a practical skill and the guidelines are periodically revised.
53 marksCuriosity Grade 8, Chapter 3, Discover, design, and debate, page 45
Invite a doctor to the school and interact with them on malnutrition, under-nutrition and over-nutrition. What would you ask, and what is the difference between these terms?
Hint. Two of the three terms are commonly treated as the same thing, and they are not.
The three terms, distinguished.
| Term | What it means |
|---|
| Malnutrition | The broad term — nutrition that is wrong in some way, whether too little, too much, or unbalanced |
| Under-nutrition | Not enough food or nutrients — leading to low weight, poor growth, weakness and reduced immunity |
| Over-nutrition | Too much food or the wrong kinds — leading to being overweight or obese |
The point worth grasping. Malnutrition is not a synonym for hunger. Both under- and over-nutrition are forms of it, which is why the chapter lists all three separately.
How this connects to the chapter. Under-nutrition links to the deficiency diseases of section 3.4.2 — scurvy, anaemia and goitre, each caused by a lack of a specific nutrient — and it weakens immunity, making infections more likely. Over-nutrition links to the non-communicable diseases of the same section, since the chapter names being overweight or obese among the causes of diabetes.
Questions worth asking the doctor:
- Can a person be overweight and still be under-nourished in some nutrient?
- Which deficiencies do you see most often in children of our age?
- What early signs should we watch for in ourselves?
- The chapter's Table 3.2 asks about excess vitamins and minerals — what happens if someone takes too much of a supplement?
- What does a genuinely balanced meal look like, using foods available here?
- How do we tell reliable nutrition advice from the misinformation online?
✦ Answer: malnutrition is the general term for nutrition that is wrong in any way, covering both under-nutrition (too little, causing deficiency diseases like scurvy, anaemia and goitre, and weakened immunity) and over-nutrition (too much or the wrong kinds, causing overweight and raising the risk of diabetes) — so a person can be overweight and still malnourished.
Solutions written by the tuition.in editorial team and checked against NCERT Curiosity - Textbook of Science for Grade 8 (hecu103.pdf), Chapter 3 'Health: The Ultimate Treasure', pages 28-45, Reprint 2026-27. HAND-WRITTEN throughout. Page count verified against the printed contents page (hecu1ps.pdf p.18): 18 pages, 28-45, matching exactly. Covers the 5 'Probe and ponder' prompts (p.28), all 7 activities (3.1-3.7), every in-text section (3.1-3.5.1), both 'Our scientific heritage' boxes (Ayurveda; variolation and teekedaars), both 'Be a scientist' boxes (Kamal Ranadive; Maharaj Kishan Bhan), both 'Think like a scientist' boxes (Jenner; Fleming), the 'Ever heard of' box on India's vaccine production, the 11 numbered 'Keep the curiosity alive' exercises (pp.42-45) and the 5 'Discover, design, and debate' projects (p.45). ALL OF TABLE 3.1 TRANSCRIBED FROM THE PDF rather than from memory - 10 diseases with causal agent, site of infection, symptoms and preventive measures, in the book's own three groupings (air-spread: common cold and influenza, chickenpox, measles, tuberculosis; water- and food-spread: hepatitis A, cholera, typhoid, ascariasis; insect-transmitted: malaria, dengue). Exercise Q7's dengue figures were transcribed and re-read: Jan 10, Feb 12, Mar 15, Apr 18, May 22, Jun 40, Jul 65, Aug 65, Sep 65, Oct 30, Nov 30, Dec 20 - so the three peak months are July, August and September at 65 each and the lowest is January at 10, with the rise beginning in June and the fall in October, which matches the monsoon and is the basis of the answer to (iii). Exercise Q10 was answered by route of transmission using Table 3.1: hepatitis A, poliomyelitis and cholera spread by faecal contamination of water, while tuberculosis and chickenpox are airborne and do not. THREE POINTS OF DELIBERATE CAUTION. (1) The 'could climate change lead to NEW types of diseases' prompt is answered as changing WHERE, WHEN and HOW MUCH existing diseases occur, with the emergence of genuinely new diseases flagged as an open research question rather than asserted. (2) The CPR project answer gives the broad current sequence and India's emergency number 112, but states plainly that CPR is a practical skill that cannot be learnt from a written description, that guidelines are periodically revised, and that it must be learnt hands-on from a qualified instructor - which is what the book itself asks by suggesting a doctor demonstrate a mock drill. (3) The four Indian scientists in the reading project are given as starting points describing the FIELD each worked in, with the student told to verify and cite sources and to note disagreement between them, rather than being handed specific dates and claims to reproduce.. Questions are referenced from the NCERT textbook for identification.
