NCERT Solutions for Class 9 Science Chapter 13 Why do we Fall Ill? provide detailed explanations for all the questions present in the NCERT textbook. These are essential tool for any student who wants to improve their understanding of basic concepts.
They are a great resource for students who want to get ahead in their studies. Chapter 13 CBSE Class 9 Science NCERT Solutions are an essential tool for any student who wants to improve their understanding of basic concepts.
Chapter 13 Why do we Fall Ill? Class 9 Science NCERT Solutions
In Text Questions
1. State any two conditions essential for good health.
Two conditions essential for good health are proper nutrition and proper sanitation or clean surroundings.
2. State any two conditions essential for being free of disease.
Two conditions essential for being free of diseases are maintaining personal hygiene and getting vaccinated against common infectious diseases.
3. Are the answers to the above questions necessarily the same or different? Why?
The answer to the above questions are not same because a person may be free of disease but it is not necessary that his mental, social or economical health may be good.
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?
Three reasons why one would think that he/she is sick and ought to see a doctor are:
(i) Symptoms such as cough, cold, fever, vomiting or loose motions
(ii) Pain, inflammation, acute itching, etc. anywhere in the body
(iii) Impairment of any of the organs.
2. In which of the following case do you think the longterm effects on your health are likely to be most unpleasant?
a. If you get jaundice
b. If you get lice
c. If you get acne
Lice and acne are acute problems of our health which can be cured in short duration. But jaundice is the disease that can have adverse effect on our health as it affects the liver. This disease is a chronic one.
1. Why are we normally advised to take bland and nourishing food when we are sick?
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.
2. What are the different mean by which infectious diseases are spread?
The different means by which infectious diseases spread are:
(i) Through Air : When an infected person sneezes or coughs, little droplets containing microbes are released into the air. These droplets may be inhaled by another person, who may become infected. For example, Common cold, influenza, tuberculosis, etc.
(ii) Through food and water : Contaminated food and water that contains bacteria that can cause diseases like cholera, hepatitis.
(iii) Via Physical contact : Many diseases spread by contact of infected person with the healthy person. For example, Fungal infections, skin diseases etc.
(iv) Sexual contact : Many diseases can be transmitted through sexual contacts. For example, Syphilis, AIDS.
(v) Through vectors : The organism that spreads a disease from a patient to the host, is called vector. For example, Malaria.
3. What precautions can you take in your school to reduce the incidence of infectious diseases?
Following precautions can be taken to reduce the incidence of infectious diseases in the school:
(i) Maintaining proper sanitation and hygienic environment
(ii) Washing hands before eating.
(iii) Staying at home during infectious diseases.
(iv) Clean school surroundings and toilets.
(v) Using clean drinking water
4. What is immunization?
When the body attains immunity against any disease by vaccination, is called immunization.
5. What are the immunization programmes available at the nearest health centre in your locality? Which of these diseases are the major health problems in your area?
Immunization programmes :
(i) Vaccination against smallpox.
(ii) BCG vaccination against tuberculosis.
(iii) Polio vaccination against polio.
(iv) Vaccination against chicken pox.
(v) DPT vaccination against tetanus, diphtheria, cough
Chicken pox, Tuberculosis and Tetanus are the major health problems.
1. How many times did you fall ill in the last one year? What were the illnesses?
(a) Think of one change you can make in your habits in order to avoid any of the above illnesses.
(b) Think of one change you would wish for in your surroundings in order to avoid any of most the above illness.
I fell ill maybe several times in the last year. I suffered from dengue, cold, cough and fever.
(a) I will always drink purified and clean water and wash my hands before eating any food item. For avoiding getting malaria and dengue, one should use a mosquito repellent or sleep under a mosquito net.
(b) Maintaining cleanliness in the surroundings, not having stagnant water in pots or pans and spraying open drains with kerosene oil can help.
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?
A doctor/nurse/health worker when exposed to sick people :
(i) Use mask, gloves, etc. to avoid the direct contact with the person suffering from infectious diseases.
(ii) By taking care of their hygiene.
(iii) Wash hands with soap before drinking water or eating food.
(iv) Proper washing of exposed parts after coming in contact with infected persons.
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 bring down the incidence of these diseases.
Common diseases are dysentery, dengue and viral fever.
Suggested measures to be taken by the authorities are:
(i) Spraying of insecticides to kill the vectors of dengue.
(ii) People should be made aware about the preventive measures through health education programmes.
(iii) Providing safe and germfree drinking water to avoid spreading of cholera and typhoid.
4. A baby is not able to tell his/her caretakers that she/ he is sick. What would help us to find out?
(a) That the baby is sick?
(b) What is the sickness?
(a) The symptoms like body temperature, fever, cough, cold, loose-motions, non-stop crying
improper or no food intake, etc. would help us to find that the baby is sick.
(b) The symptoms could help us to find out the sickness of the body.
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?
In condition (c) she is more likely to fall sick as she has just recovered from malaria but her immune system is still weak and she is not taking proper diet. At this stage her body will not be able to fight against infection and if she is taking care of someone else suffering from chicken pox even she can get infected with chickenpox virus and will fall sick again.
6. Under which of 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?
(c) When your friend is suffering from measles, as it is an infectious disease.