Class 9 Science Chapter 13 Solution – Why Do We Fall Ill | SEBA Assam

Class 9 Science Chapter 13 – Why Do We Fall Ill – All Textual Solutions | ASSEB Assam (English Medium)

Class 9 Science Chapter 13 – Why Do We Fall Ill Complete Textual Questions and Solutions (ASSEB / SEBA Assam – English Medium)

The thirteenth chapter of the Class 9 Science (English Medium) syllabus, ‘Why Do We Fall Ill’, is an essential biology and public health chapter that helps students understand the significance of health and the causes of diseases. Based on the latest guidelines of the new ASSEB (Assam State School Education Board) syllabus and the New Education Policy (NEP), this comprehensive textual question-answer guide has been prepared for upcoming board examinations. This exclusive collection includes Very Short Answers (VSA), Short Questions, Long Answers, and conceptual explanations. Ospin Academy presents these solutions in an easy, 100% accurate, and completely exam-oriented format.

In this chapter, ‘Why Do We Fall Ill’, students explore the distinction between being ‘healthy’ and ‘disease-free’. The chapter thoroughly covers the classification of diseases into acute and chronic, as well as infectious and non-infectious diseases. Furthermore, it delves into the various pathogens (viruses, bacteria, fungi, protozoa), their means of spread, and the fundamental principles of treatment and prevention, including the vital concept of immunization. For students preparing for their exams, mastering these health-related concepts is highly important. Our textual solutions cover not only the textbook exercise questions but also additional crucial questions that frequently appear in the board exams, ensuring students are perfectly prepared.

What you will learn and get from these Textual Solutions:

  • Detailed explanations defining health and distinguishing it from merely being disease-free.
  • Flawless answers differentiating between acute and chronic diseases, and infectious and non-infectious diseases.
  • Clear, easy-to-understand explanations of how infectious diseases spread (air, water, vectors, sexual contact).
  • Comprehensive solutions covering the principles of treatment and the principles of prevention (including vaccination/immunization).
  • Important questions and the latest pattern of MCQ solutions according to the new syllabus format.

Special Features of Ospin Academy’s Question & Answers:

  • Complete textual solutions prepared strictly according to the current ASSEB new syllabus.
  • 100% accurate, high-quality notes written in simple English, making it easy for Class 9 students to grasp complex health and biological terms.
  • Simplified breakdowns specifically curated for quick revision before exams.
  • An exclusive collection of extra important reasoning questions (e.g., why antibiotics do not work against viral infections) that carry a high probability of appearing in the exams.

Keeping the academic success of students in mind, Ospin Academy has provided these special textual solutions. Start your exam preparation today and step forward towards scoring the highest marks in your Science examinations.

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Chapter 13 – “Why Do We Fall Ill”

Class 9 Science

Chapter – 13 Ospin Academy

Why do we Fall ILL

TEXTUAL QUESTIONS AND ANSWERS

Page No.178

1. State any two conditions essential for good health.

Answer:- Two conditions essential for goods health are mentiomed below:

(i) Nutritious food.

(ii) Exercise.

2. State any two conditions essential for being free of disease.

Answer:- Two conditions essential for free of disease are mentioned below:

(i) To be in hygienic environment.

(ii) To take balanced food in sufficient amount.

3. Are the answers to the above questions necessarily the same or different? Why?

Answer:- No, the answers to the above questions (Q. 1 and Q.2) may not necessarily be the same. This is because the state of being free of disease does not always ensure a good health. An individual can have a poor health with a disease free body.

Moreover, when we are concerned about health, we have to deal with the state of well-functioning of the people of a society. But when we talk about disease, we are concerned with one’s individual disease or his suffering. Also one may be free of disease, but may not be in a good mental or social health.

Textbook Page No. 180

1. List any three reasons why you would think that you are sick and ought to see a doctor. If only one of these symptoms were present, would you still go to the doctor? Why or why not?

Answer:- Symptoms such as a headache, stomach pain, nausea, vomiting, fever, etc., make us feel that we are sick and must visit a doctor. These symptoms basically

indicate that there might be a disease, but we cannot predict the kind of disease. Therefore, it becomes necessary to visit a doctor so that the disease can be identified and can be treated with proper medication.

However, if only one of these symptoms is present, we usually do not visit a doctor. This is because such symptoms do not have much effect on our general health and ability to work. However, if a person is experiencing these symptoms for quite sometime, then he needs to visit a doctor for proper treatment.

2. In which of the following case do you think the long-term effects on your health are likely to be most unpleasant?

(i) If you get jaundice.

Answer:- Jaundice because it is a chronic disease and it takes a long time to be cured. It affects the liver and weak the digestive system of our body. Moreover it does not spread rapidly. It takes a long time to develop as well.

(ii) If you get lice.

Answer:- If you have body lice, first bathe with soap and water. After bathing, apply permethrin (Nix) to the affected areas before bedtime and then shower in the morning. Repeat this treatment nine days after the first application. Also take other measures to get rid of body

(iii) If you get acne Why?

Answer:- ‘Acne is caused by having dirty skin and poor hygiene’

Most of the biological reactions that trigger acne occur beneath the skin, not on the surface, so the cleanliness of your skin has no effect on your acne. Washing your face more than twice a day could just aggravate your skin.

Page No.187

1. Why are we normally advised to take bland and nourishing food when we are sick?

Answer. Bland and nourishing food is essential a sick person as it provides nutrients and energy to fight off the disease causing foreign elements. As a result of which the immune system of the body functions properly over a short per d of time.

2. What a the different means by which infectious diseases are spread?

Answer:- The differences means of infectious diseass are spread are:

(i) Water: Contaminated drinking water carry disease causing microbes which affects human body on drinking. For example, cholera.

(ii) Air: Some microbes spread through the little droplets thrown out by an infected person who sneezes or coughs. If someone standing close by breathes these droplets, the infection may spread to that person. Then microbes get chance to start a new infection. For example, common cold, pneumonia and tuberculosis.

(iii) Sexual contact: Sexual contact between two person can transmit various microbial diseases such as syphilis, AIDS, etc.

(iv) Animals: Animals can carry infectious agents from sick person to others. These animals are intermediates and termed as vectors. For example, mosquitoes (female Anopheles mosquitoes causes spread of malaria).

Class 9 science

3. What precautions can you take in your school to reduce the incidence of infectious diseases?

Answer:- Schools can implement several measures to minimize the spread of infectious diseases:

(i) Promoting healthy eating practices during breaks and meal times.

(ii) Ensuring access to clean, safe drinking water for everyone.

(iii) Regularly sanitizing restrooms and maintaining hygiene in toilets.

(iv) Covering the mouth and nose with a tissue or elbow when sneezing/coughing.

(v) Eliminating stagnant water in containers or outdoor areas to deter mosquito breeding. t

4. What is immunisation?

Answer:- Immunisation is a process by which a mild type of infectious microbe is introduced into the body by vaccination or by other means to activate the immune system against a particular infection or disease (by producing antibody in blood cells). This increases the immunity of the body against that particular disease.

5. What are the immunisation programmes available at the nearest health centre in your locality? Which of these diseases are the major health problems in your area.

Answer:- The immunisation programmes available at the nearest health centre are mentioned below:

1. BCG Vaccine: Protects against tuberculosis (TB), administered shortly after birth via intradermal injection .

2. Polio Drops (bOPV): Prevents poliomyelitis, given orally at 4 months and 4 years of age as part of a multi-dose schedule .

3. MMR Vaccine: Guards against measles, mumps, and rubella, with doses at 8 months and 18 months .

4. DPT/DTaP Vaccine: Targets diphtheria, pertussis (whooping cough), and tetanus, administered in a 5-dose series starting at 3 months .

5. Hepatitis Vaccines: Includes Hepatitis B (HepB) given within 24 hours of birth and Hepatitis A (HepA) for children aged 12–24 months .

EXERCISES

Textbook Page No. 188

1. How many times did you fall ill in the last one year? What were the illnesses?

(a) Think of one change you could make in your habits in order to avoid any of/most of the above illnesses.

Answer:- Since this is a personalised question, therefore, the answer may vary from person to person. Here the answer assumes some facts which may be representative Two times in the last year. The illnesses are malaria and dysentery.

(i) To take protective measures against mosquito biting and prevent mosquito breeding by avoiding accumulation of stagnant water.

(ii) To take nutritious food and drink boiled and filtered water.

(b) Think of one change you would wish for in your surroundings in order to avoid any of/most of the above illnesses.

Answer: Change in surroundings to avoid such illnesses are: The surrounding environment should be totally free from any waste material or garbage and stagnant water.

2. A doctor/nurse/ health-worker is exposed to more sick people than others in the community. Find out how she/ he avoids getting sick herself/ himself.

Answer:- A doctor/nurse/ health- worker is exposed to more sick people.

(i) Maintaining personal hygiene, e.g. washing hands with soap/handwash/sanitizer after handling every patient or medical equipments.

(ii) Wearing a mask to prevent the transmission of microbes through air when in contact with a patient.

(iii) Wearing hand-gloves to avoid direct physical contact with the patient.

3. Conduct a survey in your neighbourhood to find out what the three most common diseases. Suggest three steps that could be taken by your local authorities to bring down the incidence of these diseases.

Answer:- Survey of different areas may represent varying results.

Three most common diseases are malaria, dysentery and viral fever.

Steps to be taken by the local authorities to bring down the incidence of these diseases are:

(i) Removing garbage and all waste materials from the streets, medical and nursing home campuses, etc. and scientifically disposed off.

(ii) Spraying chemicals in residential areas to kill mosquitoes and cleaning all stagnant water to avoid their breeding.

(iii) Supplying safe drinking water.

4. A baby is not able to tell her/ his caretakers that she/he is sick. What would help us to find out

(a) That the baby is sick?

Answer:- (a) Appearance of some symptoms are the signs of sickness. Symptoms may be cough, fever, loose motion, vomiting, etc.

(b) What is the sickness?

Answer: By observing the symptoms we may get an idea about the disease, e.g. yellow colour of eyes and urine with or without fever indicates initiation of jaundice. Further clinical investigation should be done for proper diagnosis and treatment.

5. Under which of the following conditions is a person most likely to fall sick?

(a) when she is recovering from malaria.

(b) when she has recovered from malaria and is taking care of someone suffering from chickenpox.

(c) when she is on a four-day fast after recovering from malaria and is taking care of someone suffering from chickenpox. Why?

Answer:- (c) When she is on a four-day fast after recovering from malaria and is taking care of someone suffering from chickenpox.

6. Under which of the following conditions are you most likely to fall sick?

(a) when you are taking examinations.

(b) when you have travelled by bus and train for two days.

(c) when your friend is suffering from measles. Why?

Answer:- (c) When my end is suffering from measles.

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Note – If you find any mistakes in this chapter, please let us know or correct them yourself while reading. Thank you!
Class 9 Science Chapter 13 (Why Do We Fall Ill) – Frequently Asked Questions (FAQs)
What are the main topics covered in Class 9 Science Chapter 13?
Chapter 13, ‘Why Do We Fall Ill’, covers the concept of health and its failure, acute and chronic diseases, infectious and non-infectious causes, various pathogens, modes of transmission, principles of treatment, and principles of prevention including immunization.
Does this guide provide details on preventive measures and vaccines?
Yes, this solution set provides comprehensive answers detailing general preventive measures (hygiene, safe water) as well as specific preventive measures like vaccination and immunization processes.
Are these solutions based on the latest ASSEB syllabus?
Absolutely. All study materials, biology notes, and solutions provided here are strictly prepared according to the new ASSEB syllabus and current rationalized guidelines.
What type of questions can be expected from this chapter in the exams?
Students can expect questions differentiating between healthy and disease-free states, matching pathogens to their respective diseases, reasoning questions on why certain treatments are used (like antibiotics for bacteria, not viruses), and the concept of immunization.

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