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Chapter 13 - Why Do We Fall ILL

In this chapter, you’ll study about ‘health’ and the reasons why we fall ill. Our body is made up of numerous cells which are very active in nature. If these cells come in contact with harmful microbes, they stop functioning properly, leading to a disharmony in the body. This leads to various diseases, some of which are infectious and some are non-infectious in nature. For healthy living, not only personal hygiene is important, even the hygiene of the community is equally necessary. This is because lack of cleanliness can lead to various diseases, which can even be acute or chronic diseases. In this chapter, you’ll also learn how infectious diseases are spread and how to prevent and treat such diseases.

A clear understanding of NCERT Solutions for Class 9 Science, Chapter 13 is important for you to get in-depth knowledge on healthy living, various diseases, their causes, preventions and treatments.

Let’s take a look at topics and sub-topics of Class 9 Science Chapter 13, Why do we fall ill?

13.1 Health and its Failure

13.1.1 The significance of ‘health’

13.1.2 Personal and community issues both matter for health

13.1.3 Distinctions between ‘healthy’ and ‘disease-free’

13.2 Disease and Its Causes

13.2.1 What does disease look like?

13.2.2 Acute and chronic diseases

13.2.3 Chronic diseases and poor health

13.2.4 Causes of diseases

13.2.5 Infectious and non-infectious causes

13.3 Infectious Diseases

13.3.1 Infectious agents

13.3.2 Means of spread

13.3.3 Organ-specific and tissues specific manifestations

13.3.4 Principles of treatment

13.3.5 Principles of prevention

In Class 9 Science Chapter 13, you will learn -

Section 13.1 – In this section, you’ll learn what is the actual meaning of being healthy, how personal as well as community issues matter in a healthy living, why public cleanliness, social equality and harmony are important for individual health and what is the difference between being ‘healthy’ and being ‘disease-free’.

Section 13.2 – In this section, you’ll study what is a disease, how does our body react when we are suffering from a disease, what are acute or chronic diseases, effect of chronic diseases in our body, difference between acute and chronic diseases, what are the causing of diseases and what are infectious and non-infectious diseases.

Section 13.3 – In this section, you’ll acquire knowledge about infectious diseases and about microbes that cause infectious diseases such as common cold, dengue fever, influenza, AIDS and more. You’ll also learn why it is important to study infectious agents that cause diseases and how these agents spread diseases, which are also known as communicable diseases.

In this chapter, you are provided with several diagrams, activities and examples with their solutions for a clear understanding of Why do We Fall ill? To know more about NCERT Solutions for Class 9 Chapter 13 you should explore the exercises mentioned in this chapter. You can also download the Sound Class 9 Solutions PDF, solved by our science experts.

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