Wuchereria bancrofti is transmitted by

Sickle cell aneamia is more common in South Africa. This is due to

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 ?

Opioids are the drugs, which bind to specific opioid receptors present in our