---
title: "NCERT Solutions Class 8 Science Health: The Ultimate Treasure"
url: https://www.swavid.com/science/class/8/chapter/health-the-ultimate-treasure/ncert-solutions
dateModified: 2026-10-07T16:13:21+00:00
---

# NCERT Solutions Class 8 Science Health: The Ultimate Treasure

This chapter's questions cover the understanding of health, communicable and non-communicable diseases, their causes, prevention, and treatment. They also explore immune responses, vaccination, lifestyle factors, and antibiotic resistance through analysis, surveys, and practical scenarios.

Free PDF (12 pages): https://www.swavid.com/api/seo/pdf/ncert/science/class-8/swavid-ncert-solutions-class-8-science-chapter-3-health-the-ultimate-treasure-5267d945e2.pdf

## Probe and ponder

### Question z

*3 marks · Short answer*

How does your body respond to an infection such as common cold?

**Solution**

1. The body has a special system called the immune system that helps fight against diseases.
2. When a pathogen like a virus enters the body, the immune system recognizes it as a threat.
3. The immune system then attacks the pathogen to protect the body and help it recover from the infection.

**Answer:** The body uses its immune system to recognize and attack harmful pathogens, which helps the body fight off infections like the common cold.

> Common mistake: Confusing the immune response with the symptoms of the disease itself.

### Question z

*3 marks · Short answer*

We rarely see cases of smallpox or polio these days, but diseases like diabetes and heart problems are more common. Why?

**Solution**

1. Smallpox and polio have become rare due to successful mass vaccination campaigns that trained our immune systems to fight these pathogens.
2. Non-communicable diseases like diabetes and heart problems are becoming more common due to changes in lifestyle.
3. These changes include eating more processed food, lack of physical activity, and environmental factors.

**Answer:** Vaccination has successfully controlled infectious diseases like smallpox and polio, while non-communicable diseases are rising due to unhealthy lifestyle choices and environmental factors.

> Common mistake: Failing to distinguish between the causes of communicable and non-communicable diseases.

### Question z

*3 marks · Short answer*

Could climate change lead to new types of diseases?

**Solution**

1. Climate change can alter environmental conditions, such as temperature and rainfall patterns.
2. These changes can create favorable conditions for the breeding of vectors like mosquitoes.
3. An increase in vector populations can lead to a rise in the spread of diseases like malaria and dengue.

**Answer:** Yes, climate change can lead to new or increased disease outbreaks by altering environments to favor the spread of vectors like mosquitoes.

> Common mistake: Not linking climate change to the spread of vectors.

### Question z

*3 marks · Short answer*

How do emotions like stress or worry affect us and make us sick?

**Solution**

1. Emotions like stress and worry affect our mental well-being and can physically impact our health.
2. Stress can disrupt our sleep, eating habits, and daily routine, leading to lifestyle-related issues.
3. Prolonged stress and worry can make the body more prone to illness and affect overall well-being.

**Answer:** Emotions like stress and worry can negatively affect our mental and physical health by disrupting sleep and eating habits, making the body more prone to illness.

> Common mistake: Writing only about mental health without mentioning how emotional stress impacts physical health and habits.

### Question z

*3 marks · Short answer*

Why do some groups of people get affected more than others during disease outbreaks?

**Solution**

1. People have different levels of immunity, which is the natural ability of the body to fight diseases.
2. Environmental factors, such as living in clean or polluted areas, significantly impact health.
3. Access to sanitation, hygiene, and healthcare also determines how much different groups are affected during disease outbreaks.

**Answer:** Groups are affected differently based on their individual immune system strength, their living environment, and their access to basic hygiene and healthcare.

> Common mistake: Attributing disease susceptibility only to genetics rather than environmental and social factors.

### Question z

*3 marks · Short answer*

Share your questions

**Solution**

1. How do vaccines provide long-term protection against different types of pathogens?
2. Are there natural ways to strengthen our immune system beyond maintaining a healthy lifestyle?
3. How can communities work together to improve local sanitation and reduce the spread of diseases?

**Answer:** Questions include: How do vaccines provide long-term protection? Are there natural ways to strengthen our immune system? How can communities improve local sanitation?

> Common mistake: Asking questions that are not relevant to the chapter's focus on health and disease.

## Think and Reflect

### Question 1

*3 marks · Short answer*

What was the cause of the boy's health problems? How did his habits and surroundings affect his well-being?

**Solution**

1. The boy's health problems were caused by loneliness, lack of friends, and spending excessive time on digital screens.
2. His unhealthy habits like lack of sleep and poor social interaction led to headaches, weight loss, and difficulty in sleeping.
3. His new environment without friends and busy parents negatively affected his physical and mental well-being.

**Answer:** The health problems were caused by loneliness, excessive screen time, lack of sleep, and poor social interaction in a new environment, which negatively affected both his physical and mental well-being.

> Common mistake: Only mentioning physical symptoms like headaches while forgetting to include mental and social factors like loneliness and screen time.

## Activity 3.2: Let us list

### Question z

*Activity*

List some good habits that your parents, teachers, or elders often encourage you to follow. How many of these are already a part of your daily routine? Which ones would you like to start following? Add to the list below:

**Solution**

1. Good habits encouraged by elders include keeping clean by maintaining personal hygiene, eating a healthy and balanced diet, exercising regularly, making time to relax or meditate every day, spending time with family and friends, and getting proper sleep.

**Answer:** A list of good habits like personal hygiene, balanced diet, regular exercise, and daily meditation forms a healthy daily routine.

### Question z

*Activity*

Now, think about habits that are not good for your health. Add more to the list below:

**Solution**

1. Habits that are not good for health include spending too much time on mobile phones or digital screens, eating fast food and junk food every day, sleeping very late or not getting enough sleep, skipping meals especially breakfast, and consuming harmful substances like tobacco or alcohol.

**Answer:** Unhealthy habits include excessive screen time, eating daily junk food, improper sleep cycles, and skipping meals.

## Activity 3.3: Let us compare

### Question z

*Activity*

Look at Fig. 3.3a and Fig. 3.3b. Which playground would you like to play in, and why?

**Solution**

1. We would like to play in the playground shown in Fig. 3.3a because it is clean, well-maintained, and beautiful.
2. The playground in Fig. 3.3b is polluted, dirty, unhygienic, and full of flies and mosquitoes, which can cause us to fall sick more often.

**Answer:** We would like to play in the playground shown in Fig. 3.3a because it is clean and well-maintained.

## Activity 3.7: Let us infer

### Question z

*3 marks · Short answer*

Study the infographic given in Fig. 3.5b. How do you think the antibiotic resistance has been developed in bacterial pathogens? What precautions may be taken to reduce antibiotic resistance?

**Solution**

1. Antibiotic resistance develops when antibiotics are misused or taken in incomplete doses, killing beneficial bacteria and allowing resistant bacteria to survive, multiply, and transfer resistance to other bacteria.
2. To reduce antibiotic resistance, we must use antibiotics wisely by taking them only when prescribed by a doctor, in the correct dose, and for the right duration.
3. Unnecessary use in humans and animals should be avoided to keep antibiotics effective for future generations.

**Answer:** Antibiotic resistance develops due to the misuse or incomplete dosage of antibiotics, and it can be prevented by using them only when prescribed by a doctor in the correct dose and duration.

> Common mistake: Students often write that antibiotics become resistant instead of the bacterial pathogens becoming resistant.

## Keep the curiosity alive

### Question 1

*3 marks · Short answer*

Group the diseases shown in the images as communicable or non-communicable.

**Solution**

1. Communicable diseases are caused by pathogens and can spread from one person to another.
2. Non-communicable diseases are not caused by pathogens and do not spread from person to person; they are linked to lifestyle, diet, and environment.
3. Cold and flu, Typhoid, and Chickenpox are communicable diseases.
4. Diabetes and Asthma are non-communicable diseases.

**Answer:** Communicable: Cold and flu, Typhoid, Chickenpox. Non-communicable: Diabetes, Asthma.

> Common mistake: Confusing the categories or misclassifying a disease.

### Question 2

*1 mark · MCQ*

Diseases can be broadly grouped into communicable and non-communicable diseases. From the options given below, identify the non-communicable diseases.
(i) Typhoid (ii) Asthma (iii) Diabetes (iv) Measles

- (i) and (ii)
- (ii) and (iii)
- (i) and (iv)
- (ii) and (iv)

**Solution**

1. Typhoid (i) and Measles (iv) are communicable diseases.
2. Asthma (ii) and Diabetes (iii) are non-communicable diseases.
3. Therefore, the correct option is (ii) and (iii).

**Answer:** (b) (ii) and (iii)

> Common mistake: Incorrectly identifying Asthma or Diabetes as communicable diseases.

### Question 3

*3 marks · Short answer*

There is a flu outbreak in your school. Several classmates are absent, while some are still coming to school coughing and sneezing.
(i) What immediate actions should the school take to prevent further spread?
(ii) If your classmate, who shares the bench with you, starts showing symptoms of the flu, how can you respond in a considerate way without being rude or hurtful?
(iii) How can you protect yourself and others from getting infected in this situation?

**Part (i)**

1. The school should advise students showing flu symptoms to stay home and rest to prevent spreading the infection.
2. It should promote frequent handwashing, wearing masks, and sanitizing common areas.

Answer (i): Isolate sick students, encourage them to stay home, and ensure hand hygiene and mask-wearing.

**Part (ii)**

1. Gently suggest that they take rest at home and visit a doctor so that they feel better soon.
2. Maintain proper distance politely without making them feel isolated or uncomfortable.

Answer (ii): Politely encourage them to rest at home and take care of their health.

**Part (iii)**

1. Wash hands frequently with soap and water and avoid touching the face.
2. Wear a mask in crowded places and cover the mouth and nose while coughing or sneezing.

Answer (iii): Wear masks, wash hands frequently, and avoid sharing personal items.

**Answer:** Immediate actions, considerate responses, and personal protective measures help control a school flu outbreak.

> Common mistake: Ignoring basic hygiene or reacting rudely to sick classmates instead of taking preventive measures.

### Question 4

*3 marks · Short answer*

Your family is planning to travel to another city where malaria is prevalent.
(i) What precautions should you take before, during, and after the trip?
(ii) How can you explain the importance of mosquito nets or repellents to your sibling?
(iii) What could happen if travellers ignore health advisories in such areas?

**Part (i)**

1. Before the trip, check health advisories and carry mosquito repellents and nets.
2. During the trip, wear long-sleeved clothes, use mosquito repellents, and avoid areas with still water.
3. After the trip, monitor health for any symptoms like high fever and consult a doctor immediately if needed.

Answer (i): Use repellents, wear long sleeves, sleep under mosquito nets, and monitor health after returning.

**Part (ii)**

1. Explain that mosquitoes act as vectors transmitting diseases like malaria through their bites.
2. Tell them that nets and repellents create a physical barrier preventing mosquito bites.

Answer (ii): Explain that mosquito nets and repellents block disease-carrying mosquitoes from biting.

**Part (iii)**

1. Ignoring health advisories can lead to mosquito bites and severe infections like malaria.
2. It can result in high fever, profuse sweating, periodic chills, and prolonged illness.

Answer (iii): Travellers may contract malaria, causing high fever, chills, and serious illness.

**Answer:** Precautions before, during, and after travel protect against malaria transmission by mosquitoes.

> Common mistake: Failing to use mosquito repellents or ignoring symptoms of fever after returning from a malaria-prone area.

### Question 5

*3 marks · Short answer*

Your uncle has started smoking just to fit in with his friends, even though it is well known that smoking can seriously harm health and even cause death.
(i) What would you say to him to make him stop, without being rude?
(ii) What would you do if your friend offers you a cigarette at a party?
(iii) How can schools help prevent students from indulging in such harmful habits?

**Part (i)**

1. Express genuine concern for his health and well-being without sounding judgmental.
2. Remind him that smoking seriously harms health, increases cancer risk, and can cause death.

Answer (i): Politely express concern and explain the serious health risks of smoking.

**Part (ii)**

1. Firmly refuse the offer by saying a clear 'NO' to harmful substances.
2. Walk away or encourage healthy alternatives to fit in without compromising health.

Answer (ii): Firmly refuse the offer and say 'NO' to the cigarette.

**Part (iii)**

1. Schools can conduct awareness programs and health campaigns regarding the dangers of tobacco and smoking.
2. They can provide counselling and promote healthy lifestyle habits among students.

Answer (iii): Conduct awareness campaigns, health education, and counselling sessions.

**Answer:** Smoking harms health seriously, and peer pressure should be resisted through firm refusal and healthy choices.

> Common mistake: Being aggressive when advising elders or succumbing to peer pressure at parties.

### Question 6

*3 marks · Short answer*

Saniya claims to her friend Vinita that “Antibiotics can cure any infection, so we don’t need to worry about diseases.” What question(s) can Vinita ask her to help Saniya understand that her statement is incorrect?

**Solution**

1. Ask Saniya if antibiotics work against viral infections like the common cold or flu.
2. Inquire about what happens when antibiotics are used unnecessarily or not as prescribed (antibiotic resistance).
3. Ask if there are other types of infections that antibiotics cannot cure.
4. Prompt her to think about diseases that are not caused by bacteria.

**Answer:** Vinita can ask: 'Do antibiotics work for viral infections like cold or flu?' and 'What happens if we use antibiotics when we don't need them?'

> Common mistake: Not framing questions that directly challenge Saniya's broad claim.

### Question 7

*5 marks · Long answer*

The following table contains information about the number of dengue cases reported in a hospital over a period of one year:
Make a bar graph of the number of cases on the Y-axis and the month on the X-axis. Critically analyse your findings and answer the following:
(i) In which three months were the dengue cases highest?
(ii) In which month(s) were the cases lowest?
(iii) What natural or environmental factors during the peak months might contribute to the increase in dengue cases?
(iv) Suggest a few preventive steps that the community or government can take before the peak season to reduce the spread of dengue.

**Part (i)**

1. Examine the monthly dengue data given in the table.
2. Identify the months with the maximum reported cases.
3. The dengue cases were highest in July, August, and September (65 cases each).

Answer (i): July, August, and September

**Part (ii)**

1. Review the monthly data to find the minimum number of cases.
2. The lowest number of cases (20 cases) was reported in December.

Answer (ii): December

**Part (iii)**

1. Recall that dengue is transmitted by mosquitoes which breed in stagnant water.
2. The arrival of the monsoon season provides abundant still water in puddles and containers.
3. Warm and humid conditions during these months favour rapid mosquito multiplication, increasing the spread of dengue.

Answer (iii): Monsoon rains creating stagnant water and humid weather favouring mosquito breeding.

**Part (iv)**

1. Control mosquito breeding in and around homes before the monsoon starts.
2. Avoid collection of still water in coolers, tyres, and pots.
3. Use mosquito nets, repellents, and conduct community sanitation campaigns.

Answer (iv): Clearing stagnant water sources, using mosquito repellents, and conducting community sanitation campaigns.

**Answer:** Peak dengue cases occur in July, August, and September, lowest in December, driven by monsoon conditions, and preventable by controlling mosquito breeding.

> Common mistake: Confusing viral transmission vectors with waterborne contamination.

### Question 8

*3 marks · Short answer*

Imagine you are in charge of a school health campaign. What key messages would you use to reduce communicable and non-communicable diseases?

**Solution**

1. Promote personal hygiene practices such as frequent handwashing with soap and water to prevent communicable diseases.
2. Encourage students to cover their mouths while coughing and sneezing, and keep surroundings clean to stop pathogen spread.
3. Advise eating a balanced diet, limiting screen time, avoiding junk food, and exercising regularly to prevent non-communicable lifestyle diseases.

**Answer:** Key messages should focus on personal hygiene, sanitation, and vaccination for communicable diseases, and a balanced diet, physical activity, and avoiding tobacco for non-communicable diseases.

> Common mistake: Focusing only on infectious diseases while ignoring lifestyle-related non-communicable diseases.

### Question 9

*3 marks · Short answer*

It is recommended that we should not take an antibiotic for a viral infection like a cold, a cough, or flu. Can you provide the possible reason for this recommendation?

**Solution**

1. Recall that colds, coughs, and flu are caused by viruses, whereas antibiotics are medicines that only kill bacteria.
2. Antibiotics target specific parts of bacterial cells that are absent in human cells and viruses.
3. Taking antibiotics for viral infections is ineffective and contributes to the problem of antibiotic resistance.

**Answer:** Antibiotics target bacterial cell structures and are completely ineffective against viruses like those causing colds and flu.

> Common mistake: Assuming antibiotics are universal medicines that cure all kinds of illnesses.

### Question 10

*3 marks · Short answer*

Which disease(s) among the following may spread if drinking water gets contaminated by the excreta from an infected person?
Hepatitis A, Tuberculosis, Poliomyelitis, Cholera, Chickenpox.

**Solution**

1. Identify diseases from the list that spread through contaminated drinking water and food.
2. Hepatitis A, Cholera, and Poliomyelitis spread when drinking water gets contaminated by the excreta of an infected person.
3. Tuberculosis spreads through air and Chickenpox spreads through air and direct contact.

**Answer:** Hepatitis A, Cholera, and Poliomyelitis.

> Common mistake: Including air-borne or vaccine-preventable non-waterborne diseases in the list.

### Question 11

*3 marks · Short answer*

When our body encounters a pathogen for the first time, the immune response is generally low but on exposure to the same pathogen again, the immune response by the body is much more compared to the first exposure. Why is it so?

**Solution**

1. Explain that when the body encounters a pathogen for the first time, the immune system takes time to recognise it and mount a primary response.
2. During this exposure, the immune system creates memory cells specific to that pathogen.
3. On subsequent exposure to the same pathogen, the immune system recognises it immediately and launches a much faster and stronger secondary response.

**Answer:** The immune system retains memory of the pathogen from the first exposure, allowing it to recognise and attack it much faster and more strongly the second time.

> Common mistake: Stating that the pathogen becomes weaker on the second attack instead of recognizing that the body's immune memory improves.

## Frequently asked questions

### How many total questions and exercises are in NCERT Solutions for Class 8 Science Chapter 3 Health: The Ultimate Treasure?

This chapter from the new NCERT book for the 2026-27 session includes 6 questions in Probe and ponder, 1 in Think and Reflect, 2 in Activity 3.2, 1 in Activity 3.3, 1 in Activity 3.7, and 11 in Keep the curiosity alive. You can find step-by-step solutions for all of them in the free PDF available on this page only.

### Which topics and concepts do the chapter questions cover?

The questions cover important health concepts such as the effects of emotions on health, environmental factors, immune system response, vaccination, lifestyle diseases, and antibiotic resistance. Additional topics include the differences between communicable and non-communicable diseases and precautions against insect-borne diseases like malaria.

### What are the hardest question types in this chapter and how should students approach them?

The most challenging questions are the long-answer and analytical types found in the Keep the curiosity alive section, which require data analysis of dengue outbreaks and understanding immune system memory. Students should approach them by breaking down the scientific concepts clearly and linking environmental factors to disease prevention.

### How can students write answers to score full marks in Class 8 Science Chapter 3?

To secure full marks, students must structure their answers logically by defining key scientific terms and using appropriate examples related to good health habits and disease control. Referring to SwaVid's detailed solutions provided on this page will help you learn the exact writing format required for exams.

### Is a free PDF for this chapter available for the 2026-27 academic session?

Yes, a comprehensive and free PDF covering the new NCERT book syllabus is available right here on this page. SwaVid provides accurate, step-by-step solutions for every exercise to help students prepare effectively for their exams.

## Related pages

- [Class 8 Science chapters](https://www.swavid.com/science/class/8)

Solutions written by SwaVid, a personal AI tutor for Class 6 to 10 Maths and Science. Practise this chapter free: https://www.swavid.com/start/student