‘Tuberculosis' is caused by
Bacterium
Virus
Protozoan
Malnutrition
What precautions are required in case of air borne disease such pneumonia and common cold?
All the diseases are spread by housefly except
Which one is a viral disease
$B.C.G.$ vaccine is used against
In the given flow diagram, the replication of retrovirus in a host is shown. Observe and answer the following questions.
$(a)$ Fill in $(A)$ and $(B)$
$(b)$ Why is the virus called retrovirus ?
$(c)$ Can the infected cell survive while viruses are being replicated and released ?