“On exposure with an infectious microbe does not necessarily mean developing noticeable disease”. Do you agree ? Explain with reason. If yes, how severe infections occur in our body ?
Yes. I agree with the statement.
The severity of disease manifestations depends on the number of microbes in the body. If the number of microbes is very small, the disease manifestations may be minor or unnoticed. But if the number of the microbes is large, the disease can be severe enough to be life- threatening.
The immune system is also a major factor that determines the number of microbes surviving in the body. The cells of immune system go into action each time infecting microbes enter the body. If they are successful, we do not actually come down with any disease and the manifestation of the disease will be minor. However, if the immune system fails, severe infections occur in the body.
Give two examples for each of the following :
(a) Acute diseases
(b) Chronic diseases
(c) Infectious diseases
(d) Non-infectious diseases.
Many vaccines form the public health programme of childhood immunisation for preventing infectious disease. Name any two such diseases.
Majority of children in many parts of India are already immune to Hepatitis A by the time they are five years old. Why ?
(i) Why a person suffering from AIDS cannot fight even small infections ?
(ii) In a slum area, many people are suffering from malaria. Mention any two unhygienic conditions that must be prevailing in that locality.
(iii) Why female Anopheles mosquito feeds on human blood ? [SAII – 2014]
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 ?
Who discovered ‘vaccine’ for the first time ? Name two diseases which can be prevented by using vaccines.
Classify infectious agents into different categories and also mention the diseases caused by them.
Which amongst the two diseases : acute or chronic has adverse effect on the health of a person? Explain giving a suitable example.
(i) What is an epidemic disease ?
(ii) Which organ is affected if a person is suffering from jaundice ?
Why are we normally advised, to take bland and nourishing food when we are sick ? [SAII – 2011, 2013]
What precautions can you take in your school to reduce the incidence of infectious diseases ?
Explain giving reasons :
(a) Balanced diet is necessary for maintaining healthy body.
(b) Health of an organism depends upon the surrounding environmental conditions.
(c) Our surrounding area should be free of stagnant water.
(d) Social harmony and good economic conditions are necessary for good health.
Becoming exposed to or infected with an infectious microbe (toes not necessarily mean developing noticeable disease. Explain.
Why do some children fall ill more frequently than others living in the same locality ?
State giving reasons whether the following statements are correct or not:
What is the alternate name of brain fever? Which vector is responsible for this disease?