Typhoid is caused by:

Which fish selectively feed on larvae of mosquitoes?

In higher vertebrates, the immune system can distinguish between self-cells and non-self. If this property is lost due to genetic abnormality and it attacks self–cells, then it leads to:

During injury, mast cells secrete:

During viral infection, the protein formed in host cells to resist is:

Cirrhosis of the liver is caused by the chronic intake of:

Which one of the following acts as a physiological barrier to the entry of microorganisms in a human body?

To which type of barriers under innate immunity, do the saliva in the mouth and the tears from the eyes, belong?

Short-lived immunity acquired from mother to foetus across the placenta or through mother's milk to the infant is categorised as: