Chapter 13. WHY DO WE FALL ILL | CBSE Class 9th Science | Solved Exercises

Intext Questions | Page 178

Question 1. State any two conditions essential for good health.

Answer : A good health is ideally a state of well-being physically, mentally and socially . The two conditions essential for good health are:

1. All community members must have access to basic and better health care facilities supported by the qualified medical professionals.
2. There should be good economic opportunities for all. Community members should be socially well connected for any support or sharing of resources and should have high level of cleanliness and hygiene at personal or community level

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

Answer : The two conditions essential for being free of diseases are:

1. Personal hygiene and cleanliness are necessary to stay away from diseases.
2. Individuals should take a balanced diet that contains carbohydrates, fats, proteins, vitamins, fibres, and proper quantity of water.

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

Answer : No. The answers to the above questions may not necessarily be the same. This is because a disease free state is not the same as being healthy. Good health is the ability of an individual to realise his or her full potential. Individuals can have poor health without having any identifiable disease. Also, health is related to society and community, whereas having a disease is about an individual sick person. Hence, the conditions for good health and for being disease free can be same or even different.

Intext Questions | Page 180 | Chapter 13. WHY DO WE FALL ILL | CBSE Class 9th Science

Question 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 : Symptoms such as a headache, stomach pain, nausea, vomiting, fever, etc., make us feel that we are sick and must visit a doctor. These symptoms basically indicate that there might be a disease, but we cannot predict the kind of disease. Therefore, it becomes necessary to visit a doctor so that the disease can be identified and can be treated with proper medication. However, if only one of these symptoms is present, we usually do not visit a doctor. This is because such symptoms do not have much effect on our general health and ability to work. However, if a person is experiencing these symptoms for quite sometime, then he needs to visit a doctor for proper treatment.

Question 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 : Out of above three, lice and acne have short term effects on our health where as Jaundice is chronic disease that affect the entire body and can cause long-term drastic effects on our health with much complication later. .

Intext Questions | Page 187 | Chapter 13. WHY DO WE FALL ILL | CBSE Class 9th Science

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

Answer : We are normally advised to consume bland and nourishing food when we are sick so that we can get the nutrients and energy quickly to fight off the foreign disease causing agents.

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

Answer : Diseases can be spread through various means such as air, water, sexual contact, blood, and vector.

1. Certain disease-causing micro-organisms are expelled in air by coughing, sneezing, talking, etc. These micro-organisms can travel through dust particles or water droplets in air to reach other people. For example, tuberculosis, pneumonia, etc. spread through air.
2. Sometimes causal micro-organisms get mixed with drinking water and spread water borne diseases. Cholera for example is water borne disease.
3. Sexual act between two people can lead to the transfer of diseases such as syphilis, gonorrhoea, AIDS, etc.
4. Certain diseases such as AIDS can spread via blood to blood contact during blood transfusion or pregnancy.
5. Certain diseases spread by animals called vectors. For example mosquitoes spread malaria.

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

Answer : Precautions to reduce incidence of infectious diseases are:

1. Stay away from the diseased person.
2. Cover your mouth or nose while coughing or sneezing to prevent the spread of disease.
3. Drink safe water.
4. Keep the environment clean to prevent mosquitoes from breeding.

Question 4. What is immunisation?

Answer : Immunisation defined as protection of the body from communicable diseases by administration of some agent that mimics the microbe. This suspension of killed microbes that mimics the disease-causing microbes is known as vaccine.

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 center are DPT (Diphtheria, Pertussis, and Tetanus), polio vaccine, hepatitis B, MMR (Measles, Mumps, and Rubella), jaundice, typhoid, etc. Of all these diseases, jaundice and typhoid are major health problems.

Things to remember.....

1. Health is a state of physical, mental and social well-being.
2. The health of an individual is dependent on his/her physical surroundings and his/her economic status.
3. Diseases are classified as acute or chronic, depending on their duration.
4. Disease may be due to infectious or non-infectious causes.
5. Infectious agents belong to different categories of organisms and may be unicellular and microscopic or multicellular.
6. The category to which a disease-causing organism belongs decides the type of treatment.
7. Infectious agents are spread through air, water, physical contact or vectors.
8. Prevention of disease is more desirable than its successful treatment.
9. Infectious diseases can be prevented by public health hygiene measures that reduce exposure to infectious agents.
10. Infectious diseases can also be prevented by using immunisation.
11. Effective prevention of infectious diseases in the community requires that everyone should have access to public hygiene and immunisation.

Solved Exercises
Chapter 13. WHY DO WE FALL ILL
CBSE Class 9th Science

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

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

Answer : last year, I fell ill twice . First time I suffered with Dengu Fever (Malaria) and second time with viral fever.

(a). Change in my Habit : I will observe good level of personal cleaniness and hygiene in day to day living, eating and clothing at home or work place. I will avoid dirty, dark and dingy places which may be infested with either mosquitoes or other insects.

(b). Change I would wish for in my surroundings : I would wish community places such as streets, markets, park, community centers in my surrounding should be clean free from and litters or garbage. There should be proper disposal of garbage. There should be no accumulation of stagnant water around resulting from a blocked and over flowing sewage.

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 can take following precautions to avoid getting sick herself/himself

1. Obderving best possible level of hygiene which include personal cleaniness, washing of hands with detol after attending a patient or touching medical equipments, disinfecting cloths while washing etc
2. Wearing a mask to avoid air born infections caused by exhaled air, sneezing or coughing of a diseased person.
3. Keeping yourself covered while moving around an infected place.
4. Using gloves, while making direct contact with a diseased person
5. Drinking safe water.
6. Eating healthy and nutritious food.
7. Ensuring proper cleanliness and personal hygiene.
8. Undergoing periodic self immunization

Question 3. Conduct a survey in your neighborhood 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 : Three most common diseases are:

1. Diarrhea
2. Malaria and Dengue Fever
3. Typhoide

Steps to be taken by local authorities to bring down the incidence of these diseases are:

1. As Diarrhea results from the consumption of contaminated food and water, every effort has to put in providing safe drinking water through water supply network. Food items, sweets, fruits and vegetables should be sold subject to desired level of hygienic and quality standards. Eating cut fruits sold in the open should be avoided. There should be proper garbage management and disposal of sewage.
2. As Malaria and Dengue, are both transmitted by mosquitoes, therefor as preventive measure, we can stop mosquitoes from breeding by keeping our environment clean free from clogged or accumulated water. our water bodies such as ponds, storage tanks should be cleaned periodically. There should no over flowing drainage. Pot holes, waste empty containers should be checked for accumulated rain water.
3. As Typhoid is a bacterial diseases and transmitted by food and water, which has been contaminated with the feces of an infected person. Therefor, maintaining hygiene in food and water intake is the only precaution for typhoid. Local authorities should maintain high level of cleanliness or health hygiene around community places specially in congested or slum areas thus reducing exposure to infectious agents. It should make arrangement for public toilets for people who do not have one. This will prevent people defecating in open and check the spread of Typhoide through vectors such as flies.

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?
2. what is the sickness?

Answer :

1. In the absence of any direct and clear communication from the baby, we can determine about his or her sickness by observing apparent behavioral changes such as any expression of an uneasiness or discomfort in the form of crying, aggression, frequent mood changes, loss of sleep or appetite, and erratic bowl movements if any etc.
2. The sickness is state of being affected with certain disease in which associated symptoms or signs or indications may be apparently visible. The symptoms may include physical or emotional pain, feeling of discomfort, change in body temperature, skin colour, eye colour, heart beats, general mood, food intake etc. In general term, high fever with or without shivering, head ache, cough, runny nose, irritation of eyes, unsteady breathing, unusual heart beats, vomiting, erratic bowel movements, skin rashes, paleness of body etc, are all states of sickness or being diseased .

Sickness

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 : Under condition (C), a person is more likely to fall sick when she is on a four day fast after recovering from malaria and is taking care of someone who is suffering from chicken pox. This is because after suffering from malaria, her body is already weak and the antibiotics administered for treatment may have weaken her body further. Clearly, by fasting during recovery process, she is putting her body under more unnecessary stress. This is more likely to affect her body negatively with a very weak immune system, when she is more prone to get infected with any outside infection and fall sick.
Further, one should know, Chicken-pox is highly contagious, airborne disease. It spreads easily either through coughing and sneezing by person suffering from it or through direct contact with secretions from the rash. Therefor, under such conditions, If she starts taking care of someone suffering from chicken pox, then she putting herself at an added and grave risk of getting infected from chicken pox virus and she is most likely to fall sick again with this disease. Not only this, to make the things more complicated, an untreated malaria or improper recovery from it, may result in its recurrence at any time in future thus putting life of a person in great danger.

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 traveled by bus and train for two days.
3. when your friend is suffering from measles.
   Why?

Answer : Under condition (C) we are more likely to fall sick when our friend is suffering from measles. This is because Measles is highly contageous disease which is spread either through respiration (aerosol transmission) or by direct fluid contact. Ninety percent of the people sharing accommodation with an infected person, in the absence of any precaution or immunity, are most likely to fall prey to it and become sick. Thus, if our friend is suffering from measles, we should stay away from him otherwise we might easily get infected with the disease. Remember, Measles is an infection of respiratory system, immune system and skin caused by a virus. After exposure to infection with in 10 -12 days symptoms start developing which include high fever, cough, runny nose, red eyes, spots in the mouth , rashes covering almost whole of body.