Question

The poisonous substance released as a result of rupturing in RBC of malarial patient is:
A. Haematin
B. Haemoglobin
C. Hemozoin
D. Haem

Answer 1

Hint:-Haemozoin is a biocrystal synthesised by Plasmodium and other blood feeding parasites to avoid the toxicity of free heme derived from the digestion of haemoglobin during invasion of the erythrocytes.

Complete step-by-step solution:-
In order to know about the poisonous substance hemozoin, which is released as a result of RBS’s rupturing, let us know about the complete cycle of malarial parasite:
• The sporozoites of plasmodium are infected into the human blood when its vector , a female anopheles mosquito bites the person.
• These sporozoites then enter into the liver through blood circulation.
• In the liver, they multiply sexually and rupture the liver cells and are released into the blood, where they attack fresh red blood cells. These are called merozoites.
• Inside the RBCS, merozoites develop through a ring stage of form a schizont.Schizonts divides. further to form 8-24 merozoites
• When the schizont is mature, the RBCs burst to release merozoites into the blood.
• The rupture of RBCS is associated with the release of toxic substance, hemozoin.
• This hemozoin is responsible for the chills and high fever recurring every three to four days.
• some merozoites do not develop into the schizont instead they develop into immature sexual stages
called gametocytes. During a mosquito bite, these are sucked by the female anopheles
• The male and female gametocytes fertilise and develop in the mosquito’s intestine into the mature infective stage called sporozoite.
• The sporozoites escape from the intestine and move to the salivary glands of the mosquito.
• When this infected mosquito bites another human, these sporozoites are injected into the blood through the saliva and start the liver and RBCs cycle again.
So, the correct answer is option C.

Note:- Hemozoin is an iron porphyrin proteinoid complex formed by the parasite from the breakdown of haemoglobin. It does not react with Prussian blue stain and can be removed from tissue sections by a saturated alcoholic solution of picric acid.