Widal test is used for the diagnosis of
Malaria
Pneumonia
Tuberculosis
Typhoid
The best $HLA$(Human Leucocyte Antigen) match for transplants in order of preference is
A chemical substance produced by a microorganism for inhibiting the growth of another is
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 ?
$LSD$ (Lysergic acid diethylamide) is prepared from