Class 12th Biology 2012 Set3 Delhi Board Paper Solution
Question 16
(a) Name the Protozoan parasite that causes amoebic dysentery in humans.
(b) Mention two diagnostic symptoms of the disease.
(c) How is this disease transmitted to others?
Answer
(a) Entamoeba histolytica is a protozoan parasite in the large intestine of human which causes amoebiasis (amoebic dysentery).
(b) Two diagnostic symptoms of amoebic dysentery are: (i) Abdominal pain and cramps (ii) Stools with excess mucous and blood clots.
(c) The disease is transmitted by houseflies. They act as mechanical carriers and transmit the parasite from faeces of infected person to food products, thereby contaminating them. Drinking water and food contaminated by the faecal matter are the main source of infection.
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