Class 9 Science Chapter 13 Why Do We Fall Ill

Question 1. Why are we normally advised to take bland and nourishing food when we are sick?
Answer: We are advised to take bland and nourishing food when we are sick because our body needs energy to release cells to overcome the infection, the wear and tear of body organ. The nourishing food provides nutrients to our body that will further provide energy and make new cells. No spices in the food makes its digestion process faster, does not release acids in the body that can interfere in the treatment and cure.

Question 2. What are the different means by which infectious diseases are spread?
Answer: The different means by which infectious diseases spread are:
(a) Through air: They are also called air-borne diseases. The air carries bacteria, virus and the diseases that can be caused are: common cold, influenza, tuberculosis etc.
(b) Through food and water: When one eats/drinks contaminated food/water, that contains bacteria, virus, worm etc. it can cause diseases like cholera typhoid, hepatitis.
(c) Through contact: Many diseases spread by contact of infected person with the healthy person. Example, fungal infections, skin diseases, scabies etc.
(d) By sexual contact: Many diseases can be transmitted, example, syphilis, AIDS.
(e) By body fluids: Fluids like blood, semen, mother’s milk, when infected,
can also cause diseases. Example, AIDS.
(f) Vectors: The organism that spreads a disease by carrying pathogens from one place to another is called vector. 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: The precautions that one can take in school to reduce the incidence of infectious diseases are
(a) By using handkerchief while coughing sneezing.
(b) Washing hands before eating tiffins.
(c) Staying at home if anyone suffers from infectious diseases.
(d) Getting vaccinated before the infection affects.
(e) Keeping the school surroundings clean, checking for stagnant water.

Question 4. What is immunisation?
Answer: When the body attains immunity against any disease, due to vaccination. This process is called immunisation.

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 immunization programmes available at the nearest health care centres are:

1. Child immunization programme starts from 0 to 12 years.
2. Polio eradication programme
3. H₁N₁ screening programme

In major areas tuberculosis cases are reported in a large number which is a major concern.

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 illness.
Answer: The illness was 2-3 times, common-cold, occurred in a year.
(a) One change I would make in my habits in order to avoid the above illness is that I would take proper diet rich in vitamin C and would avoid too cold food.
(b) The surroundings should be neat, and clean,

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 when exposed to sick people they keep their nose and mouth covered, take care of hygiene, wash hands with soap before drinking water or eating food. They use mask, gloves, etc to avoid the direct contact with the person suffering from infectious diseases.

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:

Question 4. A baby is not able to tell bis/her.caretakers that she/he is sick. What would help us to find out
(a) that the baby is sick?
(a) what is the sickness?
Answer:
(a) The symptoms like body temperature, fever, cough, cold, loose-motions, non-stop crying improper or no food intake etc. would help up to find that the baby is sick.
(b) The symptoms could help us to find out the sickness of the body.

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.
As the person is not taking proper diet which is required for her proper health and healing of body.
Her chances of getting chicken-pox also high as her body’s immunity has lowered.

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, as it is an infectious disease.