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15 Cards in this Set
- Front
- Back
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What are the 4 types of plasmodium that spread malaria?
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1. Plasmodium falciparum
2. P. vivax 3. P. ovale 4. P. malariae |
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Is malaria wide spread.
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Yes. It infects 300-500 million persons worldwide, resulting in 20-40 million deaths.
It is carried by the anopheles mosquito within its salivary glands, and infects humans as it feeds. |
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The different species of Plasmodium burst the red cells at different time intervals. TRUE/FALSE
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TRUE. P. vivax and ovale burst loose every 48 hours. These cycles were enumerated from 0hrs to 24hrs and 48 hrs.
0=1/24hrs=2/48hrs=3. So P vivax and ovale produce chills and fever followed by drenching sweats every 48 hrs. This is called tertian malaria. |
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P malariae bursts loose every 3 days resulting in chills in fever. TRUE/FALSE
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TRUE. This is quartan malaria.
P. falciform, the most common and deadly, bursts RBCs between 36-48hrs. |
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Plasmodia undergo sexual division in the anopheles mosquito and asexual division in the human liver and RBCs. TRUE/FALSE
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TRUE.
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What is a sporozoite?
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Thin, motile spindle shaped forms of the Plasmodia called sporozoites, swim out of the mosquitos suckers and into the human bloodstream. They find the liver and burrow into a liver cell. This is the preerythrocytic cycle.
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What is a trophozoite?
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The sporozoites round up to form a ball within the liver cell. This ball is referred to as a trophozoite, and it undergoes nuclear division, forming thousands of new nuclei.
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What is a schizont?
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After the trophozoite undergoes nuclear division, this big mass is now a cell with thousands of nuclei, called a schizont.
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What are merozoites?
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A cytoplasmic membrane then forms around each nucleus, creating thousands of small bodies called merozoites. The overloaded liver cell bursts releasing these merozoites into the blood. other liver cells may be infected again(exo-erythrocytic cycle)
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Other merozoites will enter the blood and enter RBCs starting the erythrocytic cycle, much like the exo-erythrocytic cycle(liver). TRUE/FALSE
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TRUE.
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In the erythrocytic cycle, the merozoite rounds up to form a trophozoite. TRUE/FALSE
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TRUE. IN the RBCs the trophozoite is shaped like a ring with the nuclear material looking like the diamind on a ring.
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In the RBC, nuclear division then occurs with formation of a large multinucleated schizont. TRUE/FALSE
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TRUE. Cytoplasm surrounds each nucleaus to form new merozoites within the late shizont. Red cell lysis occurs with release of merozoites,. This causes an immune response, with fever and chills, and sweats.
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What happens to the merozoites after they exit the RBCs.
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Some merozoites will change into male and female gemetocytes. These cells will be taken up by a biting anopheles, and if not, they will die.
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When you donate blood, why are you asked if you ever had malaria?
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Two species, P. vivax and ovale, produce doemant forms in the liver referred to as hynozoites which can grow years later.
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What happens when the gametocytes enter the mosquito?
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They are taken into the stomach where male and female gametocytes fuse.
DNA is mixed and these fused gametocytes become an oocyst. This oocysts divides into many spindle shaped wiggling sporozoites, which disseminate in the mosquito and find their way into the salivary glands, where they will once again be injected into the host. Asexual reproduction will procede at this stage once again. |
