NCERT Exemplar Class 9 Science Chapter 13 Solutions: Why Do We Fall Ill

NCERT Exemplar Class 9 Science Solutions for Chapter 13: Why do We Fall Ill, consists of explanations that will help you in understanding the topics of the chapter of NCERT Exemplar Class 9 Science. All the concepts of the chapter are not only important from the CBSE exam viewpoint but are also essential so as to understand the real-life scenarios.

NCERT Exemplar Class 9 Science Chapter 13 discusses diseases and all that makes you sick. Solving the exemplar questions of the book will make the preparation of CBSE exams easy for you. The chapter covers around 3 exercises with an estimate of 39 questions. The questions cover different topics of the chapter like health, disease, types of diseases, antibiotics, means of spread of infectious diseases, principles of treatment or prevention, etc.

The subject matter experts at Instasolv have aimed at explaining all the phenomenons and processes in a manner that you easily grasp all the content. The experts have years of experience and adhere to the CBSE syllabus so that the NCERT Exemplar solutions they create can help you in preparing for your upcoming tests. The solutions are written in simple and easy language.

Important Topics for NCERT Exemplar Class 9 Science Solutions Chapter 13: Why do We Fall Ill

This chapter covers all the minute details of why you fall ill. This chapter is quite interesting as it gives us knowledge of the human body and its capabilities. The important topics covered in the chapter are:


Health refers to the state of being socially, physically and mentally well so that the body can function properly.


Disease refers to the disturbance in the function or structure of any part or organ of the body. Diseases can be caused due to the attack of bacteria or any virus or even due to the lack of a nutritious diet, etc.

Types of Diseases

There are two types of diseases:

  1. Acute Disease like Flu, Common Cold, etc.
  2. Chronic Diseases like TB, Cancer, etc.


Antibiotics are the drugs or the medicines that perform to block the biochemical pathways which are crucial for bacteria. Antibiotics are used in order to cure diseases that are caused due to bacteria. These medicines never work against viral infections as a virus does not possess their own biochemical mechanism but still, everything depends on the host.

Means of Spread of Infectious Diseases

Infectious diseases spread mainly from an infected person to any healthy person through water, food, air, physical contact, etc.

Principles of Treatment

There are two types of principles of infectious diseases. Their main work is to:

  1. Reduce the effects of the symptoms
  2. Kill the microbes which are causing the diseases. 

Principles of Prevention

There are two ways in which infectious diseases can be prevented:

  1. General ways of prevention
  2. Specific ways of prevention

Other Points to Remember From the Chapter:

  • Health refers to the physical, emotional as well as social well being. 
  • An individual’s health depends on the physical surroundings. 
  • Acute or chronic are the two types of diseases. 
  • Diseases are caused due to infectious or noninfectious causes. 
  • Air, water, physical contact, etc. helps in spreading infectious agents.
  • The Prevention of a disease is always better than taking the proper treatment. 
  • Public Health hygiene measures help in preventing infectious diseases by reducing exposure to infectious agents. 

Exercise Discussion of NCERT Exemplar Class 9 Science Solutions Chapter 13: Why do We Fall Ill

  • The chapter consists of a total of 39 questions. All these questions are based on the latest exam patterns so that students like you can prepare in a better manner. 
  • The first set comprises multiple-choice questions that are around 18 in number. You will be asked to think and choose the correct option from the four given options. This exercise tests you if you have a basic understanding of the chapter. 
  • The second set of exercise has around 11 short answer questions with a combination of the answer in one word, or give justification to the statement if it is true or false, etc. this section has questions on different topics like giving examples of types of diseases, naming the diseases caused by protozoans, etc. 
  • The third set has 10 long answer questions in which you need to give a full-fledged answer to whatever is asked in the question. Different things asked are disease and its types with examples, disease symptoms, the importance of the immune system, etc. 

Benefits of NCERT Exemplar Class 9 Science Solutions Chapter 13: Why do We Fall Ill by Instasolv

  • The Instasolv platform helps you to get the exam ready as we provide you with the appropriate NCERT Exemplar Class 9 Science Chapter 13 solutions. They are accurate, easy to understand and verify. 
  • The team at our backend aims at simplifying all your doubts and keeps the course content and every topic clear to you. 

The NCERT Exemplar Problems and Solutions for Class 9 Science Chapter 13 will surely work as the best reference study material for you as it contains all the altered solutions that make this chapter easy to understand.