Why Do We Fall ill

CBSE class IX Science

NCERT Solutions
Chapter - 13
Why Do We Fall ill

(Page No. 178)

1. State any two conditions essential for good health.

Ans. Two conditions essential for good health are:

better sanitation or clean surroundings, and
availability of sufficient and nutritious food.

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

Ans. Two conditions essential for being free of disease:

Living in hygienic environment
Getting vaccinated against common infectious diseases.

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

Ans. Answers of above question (1,2) are interconnected but different. It is because being disease free does mean being healthy.

(Page No. 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?

Ans. If we have fever, headache, stomach-ache, loose motions, cough and sneeze etc we feel weak. Then we would feel that we are sick and ought to see a doctor. If only one of these symptoms are present we should still go to see the doctor. Any of these symptoms may be initial signs of a severe disease.

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?

Ans. The long-term effects on our health are likely to be most unpleasant if we get jaundice because the symptoms severely affect our internal organs and persist for long time. In contrast to jaundice, lice can be removed easily with short treatment and so is the acne. Both of these do not produce long term effects on the body.

(Page No. 187)

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

Ans. We are normally advised to take bland and nourishing food when we are sick because we are weak during illness and need complete nourishment for faster recovery. Such a food is easily digested and replenish our lost vitamins, minerals and other nutrients along with energy.

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

Ans. Infectious diseases can be spread by following means:

a) through contaminated food and water

b) through air

c) through vectors or carriers (housefly, mosquito etc)

d) through direct skin contact or sexual contact

e) through cuts and wounds

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

Ans. To reduce the incidence of infectious diseases in my school the precautions will include:

(i) providing clean drinking water

(ii) educating students about causes of infectious diseases

(iii) vaccination of students against common infectious diseases from time to time

(iv) proper sanitation or clean environment in school and its surroundings to eradicate vectors of infectious diseases

(v) by not allowing the affected students to attend the classes till they recover from infectious diseases.

4. What is immunisation?

Ans. If one person has chicken pox once, there is no chance of suffering from it again. This happens because when the immune system first sees an infectious microbe, it responds against it and then remembers it specifically. So the next time that particular microbe, or its close relatives enter the body, the immune system responds with even greater vigour. This eliminates the infection even more quickly than the first time around. This is the basis of the principle of immunization.

5. What are the immunisation programs available at the nearest health centre in your locality? Which of these diseases are the major health problems in your area?

Ans. DPT vaccine: it is for diphtheria, whopping cough and tetanus in infants.

Pulse polio vaccine: it is to prevent polio.

BCG vaccine: Bacillus Calmette Guerin vaccine for tuberculosis.

Hepatitis vaccine

TAB vaccine for typhoid.

tuberculosis and diarrhea are the major health problems in our area.

(Chapter – end)

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.

Ans. I fall ill only once last year. I had suffered from typhoid.

(a) I will avoid street food specially those which are cooked at unhygienic places

and kept uncovered.

(b) I shall keep my surroundings cleaner than earlier.

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.

Ans. A doctor/nurse/health-worker is exposed to more sick people than others in the community still they avoid getting sick themselves because they take care of the preventive measures like personal and community hygiene/cleanliness and immunisation to prevent infectious diseases. They also wash hands with soaps thoroughly after serious examination of patients.

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.

Ans. Three most common diseases in my locality are diarrhoea, malaria and tuberculosis and following steps I would suggest to be taken by our local authorities to bring down the incidence of these diseases :

i. Supply of safe drinking water and preventing incidences of open drains.

ii. Improved and hygienic environment,free of garbage and wastes thrown in the open.

iii. Eradication of mosquitoes

iv Immunisation/vaccination camps

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?

Ans. (a) Symptoms that help us to find that baby is sick, are

(i) continuous crying and restlessness in the child

(ii) improper intake of food and body temperature

(iii) loose motions

(b) Baby is suffering from diarrhoea.

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?

Ans. A person is most likely to fall sick when she is on a four-day fast after recovering from malaria and is taking care of someone suffering from chicken-pox because a four day fast will make her body weak due to improper supply of food. Also, malaria is a very fatal disease and it will take some time for the body organs to function normally. Above all, she is taking care of someone who is suffering from most fearful infectious viral disease i.e.. chicken pox, she has more chances of getting an infection due to above mentioned reasons.

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.

Ans. We are most likely to fall sick when a friend is suffering from measles since measles is an infectious/communicable disease that can spread easily from one person to the other.

Why Do We Fall ill - Solutions