A-Level BiologyYear 2023Q20
page 11 20. Trypanosoma gambiense is a parasite that causes chronic infections in humans and can evade the immune system. The graph shows the number of trypanosomes over time in a human infected with Trypanosoma gambiense. weeks from time of infection trypanosomes/mm3 blood 1500 1000 500 0 21 25 30 From the data shown, the most probable mechanism used by this parasite to evade the immune system is A antigenic variation B suppression of the host immune system C mimicry of host antigens D latency. [END OF SECTION 1. NOW ATTEMPT THE QUESTIONS IN SECTION 2 OF YOUR QUESTION AND ANSWER BOOKLET.] page 12 [BLANK PAGE] DO NOT WRITE ON THIS PAGE
Paper Source:NAH_Biology_Section1_2023.pdf
Get full Socratic AI guidance on this question — free in the Applaa desktop app
Appy Buddy guides you step-by-step toward the answer without giving it away. Type your attempt and get instant, mark-scheme-aware clues that teach you to think like an examiner.
Applaa Desktop App
Join Applaa Community
Create your own games, learn AI concepts, program interactive apps, and share with a kid-safe community approved by parents. Free forever on Windows and Mac.
Download Free
Available for Windows and macOS · COPPA Compliant
Exam Specification Info
This question is part of the UK A-Level Biology syllabus. In the actual exam, structured questions typically require linking specific keywords to gain full marks. Applaa helps you drill these topics.
Syllabus levelAdvanced Level (A-Level)
SubjectBiology
Official MarksVariable (2–6 marks)