Name the protozoans that cause:

(a) Sleeping sickness and (b) Kala-azar

Name two diseases spread by mosquitoes.

Name the organisms which cause typhoid.

Against which disease BCG vaccine is employed?

How does vaccination protect a person suffering from a disease?

Write the symptoms and disease associated with the following:

(a) When the microbe attacks the lungs.

(b) When the virus enters the liver.

Sweety suffered from chicken-pox this year. Her grandmother told her that now she would not suffer from this disease again. What are the reasons for such a saying?

What are the major sites of infection for tuberculosis?

How are diseases causing microbes spread through the air?

List the names of three diseases caused by virus stating their mode of communication in each case.

Give reasons:

(a) Majority of children in many parts of India are already immune to Hepatitis A.

(b) Chronic diseases cause more harm to the body than acute diseases.

(c) Infectious diseases are called communicable diseases.

(a) Why making anti-viral medicine is harder than making anti bacterial medicine?

(a) In which do the following acute or chronic cases do you think the long term effects on your health are caused?

What are the causes, symptoms and methods of prevention and cure of AIDS?