In the life cycle of a {Plasmodium, once the sporozoite enters the blood of the host, it invades the hepatic portal system, resulting in occurrence of change in the host body, leading to malaria
A. Sporozoite enters the hepatocytes and divides by schizogony leading to formation of cryptomerozoites
B. Inside RBCs, the micro-metacryptozoites become rounded and modify into a young trophozoites.
C. As the trophozoite grows in size, a central vacuole is developed so that the nucleus is pushed to one side into the peripheral cytoplasm, leading to amoeboid stage.
D. In Amoeboid stage the small red eosinophils granules appear in the cytoplasm of the host corpulses as Schuffner's granules} Choose the most appropriate answer from the options given below:
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To understand the {Plasmodium} life cycle in humans, break it down:
\textbf{Liver Stage (Exo-erythrocytic):} Sporozoite \(\rightarrow\) Hepatocyte \(\rightarrow\) Schizont \(\rightarrow\) Merozoites.
\textbf{Blood Stage (Erythrocytic):} Merozoite \(\rightarrow\) RBC \(\rightarrow\) Trophozoite (ring, amoeboid) \(\rightarrow\) Schizont \(\rightarrow\) New Merozoites (cause fever) OR Gametocytes (infect next mosquito).
This framework helps organize the sequence of events.
Step 1: Concept Overview:
The question requires identifying accurate descriptions of the {Plasmodium} (malaria parasite) life cycle events within the human host. This cycle involves two primary phases: the exo-erythrocytic (liver) and erythrocytic (red blood cell) stages.
Step 2: Statement Analysis:
- Statement A: Correct. Sporozoites, injected by mosquitoes, migrate to the liver and invade hepatocytes. Asexual multiplication (schizogony) within these cells produces numerous merozoites (cryptomerozoites or metacryptozoites), characterizing the pre-erythrocytic or exo-erythrocytic cycle.
- Statement B: Correct. Merozoites (metacryptozoites) released from the liver invade red blood cells (RBCs). Inside RBCs, they transform into trophozoites, initiating the erythrocytic cycle.
- Statement C: Correct. The young trophozoite develops a large food vacuole that consumes hemoglobin, displacing the nucleus and cytoplasm to the periphery, creating a "signet ring" appearance. Further growth leads to a larger, irregularly shaped amoeboid stage. This description is accurate.
- Statement D: Correct. Infections by species like {Plasmodium vivax} and {P. ovale} cause the infected RBC cytoplasm to develop fine, eosinophilic (reddish) Schuffner's granules or dots, a key diagnostic marker.
Step 3: Conclusion:
Statements A, B, C, and D accurately describe events in the malaria parasite's life cycle within the human host. Therefore, the correct answer encompasses all of them.
