Study of interaction of antigens and antibodies in the blood is

Amoebiasis is caused by

A person showing unpredictable moods, outbursts of emotion, quarrelsome behaviour and conflicts with others is suffering from

$A$ : Antibiotics like penicillin can be used to treat common cold.
$R$ : Penicillin causes lysis of viral cells.

The human liver fluke depends on how many intermediate host or vectors ?

Recognition and digestion by the phagocytes due to the coated surface of antigens by the antibodies is known as