NCERT Solutions for Class 9 Science Chapter 13 Why Do We Fall Ill?

In-Text Questions-Answer Solved

NCERT Book for Class 9 Science Page 178

1. State any two conditions essential for good health.

Answer:- Two conditions essential for good health are:

  1. State of Complete physical, mental and social well-being.
  2. Good social and economical condition.

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

Answer:- Two conditions essential for being free of disease:-

Personal,community and domestic hygiene.

Getting pre- vaccination and proper medicines whenever required.

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

Answer:- The answers to the above questions are same to some extent but they are actually very different. Because being free of diseases means that the person is physically fit but for having good health a person should be physically as well as mentally and socially well.

NCERT Book for Class 9 Science Page 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:- The three reasons we would think that we are sick and ought to see a doctor are following:-

  1. Headache
  2. Fever
  3. Cough and cold

We generally not go to the doctor if only one of these symptoms were present because it does not affect the general health or the ability to work. But if these symptoms last for a long period then we would definitely visit the doctor.

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

  • if you get jaundice,
  • if you get lice,
  • if you get acne.

Why?

Answer:- From the above mentioned cases getting lice and acne are acute problem and can be cured easily without any serious effects on our health. But jaundice is a chronic disease and it can harm our liver badly, its long term effects on our health can be fatal.

NCERT Book for Class 9 Science Page 187

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

Answer:- The  bland and nourishing food  provides nutrients to our body that further provides energy and make new cells. No spices in the food makes its digestion process faster. It does not release acids that can interfere in the treatment and cure.

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

Answer:- The different means by which infectious diseases spread are following:

  1.  Through air: Such diseases are called air-borne diseases. Example- common cold, influenza, tuberculosis etc.
  2.  Through food and water: Contaminated food or water, that contains bacteria, virus, etc. can cause diseases like cholera typhoid, hepatitis.
  3.  Through contact: Many diseases can be spread by the contact of infected person with the healthy person. Example, fungal infections, skin diseases, scabies etc.
  4.  By sexual contact: Diseases like syphilis, AIDS can be transmitted through sexual contact.
  5.  By body fluids: Infected fluids of human body for example- blood, semen, mother’s milk, can also cause disease like AIDS.
  6.  By Vectors: Disease can be spread through vector by carrying pathogens from one place to another. Example, mosquitoes are vectors that carry pathogens like protozoa.

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

Answer:- (a) Using a handkerchief while coughing or sneezing is one of the precautions that can be taken at school to prevent the incidence of infectious diseases.

(a) Before eating tiffins, wash hands.

(b) Keeping everyone at home if anyone has an infectious disease.

(d) Getting vaccinated before the infection has a chance to take hold.

(e) Maintaining a clean environment around the school and inspecting for standing water.

 

 

Question:- 4. What is immunisation?

Answer:- Immunisation is a means of boosting our immune system with the use of vaccines that help the body fight infectious diseases.

 

 

Question:- 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 following immunisation programme is available in our neighbourhood at the nearest health centre.

  1. DPT, BCG, polio, measles, and MMR vaccinations for babies.
  2. Typhoid, TT, DT, small pox, and TAB for youngsters.
  3. TT and hepatitis B for pregnant women.

In our community, diseases such as typhoid, polio, and measles are important health concerns.

 

Exercises

Question:- 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.

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

Answer:-  I fell ill thrice in the last year with a typical cold.

(a) One behaviour change I would do to avoid the illness is to eat a proper vitamin rich diet and avoid eating foods that are too cold.

(b) The environment should be neat and tidy.

 

 

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:- When exposed to sick people, a doctor, nurse, or health worker covers their nose and mouth, maintains hygiene, and washes their hands with soap before drinking water or eating food. To avoid direct contact with people who are infected with contagious diseases, they wear masks, gloves, and other protective gear.

 

 

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, typhoid, and diarrhoea are the three most common diseases in my neighbourhood. The diseases are spread primarily through unsanitary conditions.

 The government should pay attention to this. 

  1. Garbage disposal
  2. Drain cleaning with insecticides sprayed on a regular basis
  3. Providing clean drinking water

 

 

Question:- 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?

(b) what is the sickness?

Answer:-  (a) Symptoms such as body temperature, fever, cough, cold, loose stools, nonstop crying, inappropriate or no food intake, and so on might help to determine whether or not the baby is sick.

(a) The symptoms may help us in determining the nature of the body’s illness.

 

 

Question:- 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 chicken-pox.

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

Answer:-  (c) when she is on a four-day fast after recovering from malaria and is taking care of someone suffering from chicken-pox. Because She isn’t eating the right foods, she isn’t getting the nutrition she needs to be healthy and mend her body.

Her chances of contracting chicken pox are also high because her immunity has weakened.

 

 

 

Question:- 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 your friend is suffering from measles. Because Measles is a communicable disease that spreads by nasal or throat discharge in young children.