ICSE Class 9 Answered

A vector merely transports the disease and does not have any traces of the disease in its immune system and can transmit the disease to other organisms.

A carrier has the infectious agent, but does not show any symptoms of the disease and can transmit the disease to other organisms.

Mosquitoes are vectors of malaria because the malarial parasite; Plasmodium vivax lives in the stomach lining of the mosquito. It can cause the spread malaria.