A-Level BiologyYear 2020Q2
5 Turn over 2 Acetylcholine is a neurotransmitter produced by the parasympathetic nervous system. (a) Describe the process by which acetylcholine is released from a synapse. 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(b) Some chemical pesticides, such as diisopropyl fluorophosphate (DFP), affect the activity of synapses. This pesticide acts by binding irreversibly to the R group of an amino acid in the active site of acetylcholinesterase. (i) Explain why DFP inhibits the activity of acetylcholinesterase. 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(Total for Question 2 = 9 marks)
Paper Source:9BI0_02_que_20201017.pdf
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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)