AQA GCSE Protist diseases (Biology)
Protist diseases
Protists are eukaryotic organisms.
This means that they have a cell membrane, cytoplasm and their genetic material is found inside the nucleus.
Malaria
Malaria is a disease caused by a protist called Plasmodium.
The female Anopheles mosquito acts as a vector for Plasmodium, transferring it from an infected human to an uninfected human.
Malaria causes recurrent episodes of fever and can be fatal.
Life cycle stages
The malarial protist has a life cycle that includes the mosquito and the human host.
1.Female mosquito will take a blood meal from a human who is infected with malaria. The mosquito uses this blood meal to feed their young.
2.The female mosquito, which now has the plasmodium will take a 2nd blood meal from another human, this time an uninfected one. Just before leaving, the mosquito will clean its stylet, which injects the plasmodium into the uninfected human, causing transmission.
3.Malarial parasite (plasmodium) will infect the liver cells.
4.Malarial parasite will infect the red blood cells, feeding on contents of red blood cells, causing the red blood cells to burst. When the red blood cells burst, this causes the recurring fever.
5.The human is now infected, the cycle can restart with another female mosquito.
Controlling the spread of malaria.
1. Remove still water sources, this is because mosquitoes use still water to breed.
2. Use mosquito repellent sprays.
3. Sleep under insecticide impregnated mosquito nets.
4. Use insecticide sprays to kill mosquitoes.
5. Antimalarial tablets are available. However, the Plasmodium have developed resistance to some antimalarial medications.
Practice Questions
1.How can eukaryotic cells be identified?
2. What is the name of the organism which causes malaria?
3. State 3 ways that malaria can be controlled.