‘Syphilis' is a sexually transmitted disease caused by
Treponema pallidum
Leptospira
Pasteurella
Vibrio
Cirrhosis 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 ?
Which of the following is related to humoral immunity?
Oral cancer may be caused by