Class 9 Science

Why Do We Fall Ill?

NCERT Solution

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

Answer: Last year, I suffered once from fever and twice from diarrhea.

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

    Answer: I will stop buying food items from roadside vendor.
  2. Think of one change you would wish for in your surroundings in order to avoid any of/most of the above illnesses.

    Answer: My neighborhood needs to be cleaner and drainage needs to be properly covered.

Question 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 takes good care of cleanliness. These people maintain a high level of personal hygiene. They also maintain cleanliness at their workplace. They usually wash hands after examining or attending to a patient.

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

Answer: Malaria, dengue and cholera are the most common diseases in my neighborhood.

Following steps should be taken by local authorities to bring down the incidence of these diseases:

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

  1. That the baby is sick?

    Answer: If the baby is crying too much and is restless, then baby’s caretakers get a clue about the baby being sick.
  2. What is the sickness?

    Answer: A doctor is the best person to tell about the specific disease the baby may be suffering from.

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

  1. When she is recovering from malaria.
  2. When she has recovered from malaria and is taking care of someone suffering from chicken-pox.
  3. When she is on a four-day fast after recovering from malaria and is taking care of someone suffering from chicken-pox. Why?

Answer: She is most likely to fall sick in the third condition, i.e. when she is on a four day fast after recovering from malaria and is taking care of someone suffering from chicken pox. This situation presents many risk factors. Her immunity is weak because she was suffering from malaria. She is not getting proper nutrition because of her four-day fast. Proximity to a patient of chicken pox presents further risk to her.

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

  1. When you are taking examinations.
  2. When you have travelled by bus and train for two days.
  3. When your friend is suffering from measles. Why?

Answer: The third condition presents the biggest risk. Measles is an infectious disease. So, going near that person increases the chances of getting infected.