Question.1
(i) What are the various ways to prevent the diseases ?
(ii) What is immunisation ?
Answer.
(i) We can prevent disease in two ways :
(a) General ways: By preventing exposure to infectious microbes.

•  By providing safe drinking water and public hygiene.
•  By providing proper and balanced diet, (any two)

(b) Specific ways : By immunisation.
(ii)Immunisation : The process of developing immune power in the body to fight against the diseases is called immunisation. In the process of immunisation, a vaccine is introduced into the body doe to which the immune power of the body improves.

Question.2 State two principles of treatment of a disease.
Answer. There are two ways to treat an infectious disease :
(i) By reducing the effect of the disease
(a) By symptomatic treatment. (b) By taking a bed rest
(ii) By killing the microorganisms that act as infectious agents.

Question.3 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. When there is a disease, either the functioning or the appearance of one or more systems of the body will change for the worse. These changes give rise to symptoms and signs of disease. Symptoms of disease indicate that a person is not well. These symptoms can be in the form of headache, cough, loose motions or wound with pus. These symptoms indicate that there-may be a disease but they do not indicate what the disease is. Therefore, even if you have any of these symptoms, it is advisable to go to the doctor because only he can diagnose about any signs of a disease on the basis of these symptoms. These signs will give a little more definite indication of the presence of a particular disease. But if there is only one symptom of headache, then there is no need of visiting a doctor because it could be due to Tiredness or Stress.

Question .4 What are the different means by which infectious diseases are spread ? [SAII – 2011, 2013]
Answer. The various means by which the infectious diseases get spread are :

1. Through air : This occurs through the little droplets thrown out by an infected person who sneezes or coughs. Someone standing closeby can breathe in these droplets and the microbes get a chance to start a new infection. Examples of such diseases which spread through the air are the common cold, pneumonia and tuberculosis.
2.  Through water: This occurs if the excreta from someone suffering from an infectious gut disease, such as cholera, get mixed with the drinking water used by people living nearby.
   The cholera-causing microbes will enter new hosts through the water they drink and cause disease in them. Such diseases are much more likely to spread in the absence of safe supplies of drinking water.
3. Through sexual contact: Microbial diseases such as Syphilis or AIDS are transmitted by sexual contact from one partner to the other. Other than the sexual contact, the AIDS virus can also spread through blood-to-blood contact with infected people or from an infected mother to her baby during pregnancy or through breast feeding.
4. Through vectors: There are certain animals which carry the infecting agents from a sick person to another potential host. These animals are thus the intermediaries and are called vectors. The commonest vectors are the mosquitoes which spread malaria. In many species of mosquitoes, the females anopheles need highly nutritious food in the form of blood in order to be able to lay mature eggs:

Question. 5 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/most of the above illnesses.
(b) Think of one change you would wish for in your surroundings in order to avoid any/most of the above illnesses.
Answer. I fell ill thrice in the last one year. At first time, I suffered from common cold, at second time I suffered from influenza (eye-flu) and at third time, I suffered from diarrhoea.
(a) The change which I brought in my habits to avoid any of this type of illness in near future is:
(i) To remain away from people suffering from common cold or eye-flu.
(ii) To clean hands before meals and to take purified drinking water.
(b) Availability of purified drinking water all the time throughout the year.

Question.6 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 take the following precautions to avoid getting sick herself. He/She:

1. always wear masks while diagnosing mouth or chest infections.
2. always wear hand gloves even while doing minor surgeries.
3. always clean hands as well as instruments after diagnosis of the patient.
4. makes sure that they are immunized against all contagious diseases.
5. takes balanced diet (especially rich in proteins) to build their powerful immune system.
6. dispose of any sputum, blood sample, urine or stool, properly.

Question.7 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
chickenpox.
(c) When she is on a four-day fast after recovering from malaria and is taking care of someone suffering from chickenpox. Why ?
Answer. 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 chickenpox. There are following reasons for this :

1. When a person gets a disease like malaria he has loss of appetite, vomiting and high fever. This leads to loss of body fluids and makes body very weak. Under such circumstances if she is on a four day fast, then her defense system will be totally weak and she can even collapse.
2.  With the weak immune system if she is taking care of someone suffering from chickenpox, then it is more likely that she may also get the disease.

Question.8
(a) What is immunisation ?
(b) Define immunity and vaccination.
(c) Define vaccine. .
(d) What type of diseases can be prevented through vaccination ? [SAII -2013]
Answer.
(a) Immunisation is a process of inoculation (injecting) of substance (vaccine) into a healthy person in order to develop immunity against the disease.
(b) Immunity is the ability of a body to recognise, destroy and eliminate external disease-causing agents. This immunisation is done by giving vaccine and thus it is also known as vaccination.
(c) The vaccine is a solution containing the disease-causing organisms in a diluted or weakened form. It may have organisms in living or even dead form.This does not actually cause the disease but this would prevent any subsequent exposure to the infecting microbe from turning into actual disease.
(d) Protection against diseases like smallpox, rabies, polio, diphtheria, chickenpox and hepatitis is provided through vaccination. It has been possible to eradicate smallpox from all regions of the world through a massive vaccination programme.

Question.9 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. After conducting a survey, I have found the following three most common diseases in my locality.
Place of study : Jalandhar (Punjab- India)

Question.10 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) The following symptoms will help us to find out that the baby is sick :
(i) Repeated crying and not responding to any stimuli.
(ii) High body temperature.
(iii) Loose motions.
(iv)Drooping of eyes.
(v) Redness of eyes.
(b) The following signs will help us to find out what is the sickness :
(i) Yellowing of eyes, pale skin and passing of yellow urine indicate that baby is suffering from jaundice.
(ii) Redness in the eye and persistent rubbing of eyes indicate about eye-flu.
(iii) Gripping pain in the stomach, loose skin and repeated loose motions indicates about diarrhoea.
(iV) High fever, headache, nausea, muscular pains and feeling very cold and shivering indicates about malaria.
(v) If only fever is there with no other visible symptoms then laboratory tests are to be done which will reveal about the signs of any disease.

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NCERT Solution : Why do we fall ill?

MCQs: Why do we fall ill?

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