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19(a) Name ONE example of a disease caused by a macro-parasite - HSC - SSCE Biology - Question 19 - 2007 - Paper 1
Question 19
19(a) Name ONE example of a disease caused by a macro-parasite. (b) List TWO features of prions that distinguish them from protozoans. (c) Mos... show full transcript
Worked Solution & Example Answer:19(a) Name ONE example of a disease caused by a macro-parasite - HSC - SSCE Biology - Question 19 - 2007 - Paper 1
Step 1
Step 2
List TWO features of prions that distinguish them from protozoans.
Answer
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Prions are infectious proteins that lack nucleic acids, while protozoans are unicellular organisms with complex cellular structures and DNA.
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Prions cause neurodegenerative diseases by misfolding normal proteins, whereas protozoans can reproduce and have various mechanisms of transmission.
Step 3
Relate this statement to a named infectious disease you have studied.
Answer
In the case of HIV/AIDS, the virus must first be transmitted through bodily fluids, such as blood or sexual contact, to enter the human body. Once inside, the virus specifically targets the immune system's CD4 cells and begins to replicate, ultimately leading to a weakened immune response and increased susceptibility to infections.