NCERT Class 9 Biology Why Do We Fall Ill CBSE Board Sample Problems

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1. Interferon are Protein.

2. Living organisms carrying the infecting agent from one person to another are calied

3. Many skin diseases are caused by

4. Virus, bacterium and protozoan can be causal agent of disease

5. Pneumonia targets organ.

One mark question

1. Who discovered vaccine?

2. Name bacteria which cause acne?

3. Penicillin is not effect against common cold. Why?

4. Name the causal agent which causes cholera?

5. Name a vaccine which saves the life of baby from three diseases?

Two marks questions

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

2. Name two diseases caused by protozoan with their causing agent?

3. Which bacterium causes peptic ulcers? Who discovered the pathogen?

4. Being disease free is not same as being healthy. Explain this statement.

5. What is immunization?

Five marks questions

1. Describe AIDS disease? Why it is considered as syndrome?

2. What are different means by which infectious diseases can spread? Explain with example?

3. Prevention is better than cure. Justify this statement with three reasons. Suggest three methods to prevent the spread of infectious diseases.