Pearson Edexcel International GCSE in Biology · 4BI1 · Free · no account needed
Synapses and the Reflex Arc — exam questions
9 original Incandio exam-style questions on Synapses and the Reflex Arc, 18 marks, about 18 minutes of writing. Each one carries the command word, the tariff and the specification statement it assesses, exactly as a paper presents them. This is an original Incandio practice question, written to reflect the structure and demands of the qualification. It is not an official Pearson Edexcel past-paper question.
This is the practice set for Synapses and the Reflex Arc — the lesson that teaches it. Read the lesson first if the idea is new; come here when you want to find out whether you can turn it into marks. Completely free, no account needed to read.
What these questions ask of you
6 command words run through this set, and on Pearson Edexcel International GCSE Biology each one means something precise. Answering the wrong command is the commonest way a candidate who understands the lesson still loses the mark.
- Which (1 mark)
- one option chosen from the set given
- Name (1–2 marks)
- the correct term, spelled recognisably
- Give (1–2 marks)
- a short factual answer drawn from recall or from the data
- Describe (2–4 marks)
- developed, linked statements of WHAT happens — no reason required, but detail is Misread as: giving one bare statement where the tariff asked for a developed account
- Explain (2–4 marks)
- a causal chain — WHY it happens, each link a separate marking point Misread as: describing what happens without giving the reason it happens
- Suggest (1–3 marks)
- a plausible answer applying taught biology to a situation not taught
Assessed on Paper 1 (4BI1/1B) and Paper 2 (4BI1/2B), against AO1, AO2, AO3.
Where these sit in the specification
Pearson Edexcel International GCSE Biology (4BI1) — statements 2.89 · 2.90. Incandio is aligned to this specification; it is not published by, endorsed by or affiliated with Pearson, and it reproduces none of Pearson's wording.
The 9 questions
Answer them on paper, then open the lesson's exam practice to have them marked. The mark scheme, the accepted and rejected answers and the annotated model answer are in Incandio and are not printed here — an answer beside its question is not practice.
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Table 1 — the effect of three substances on the time taken for a reflex response in an isolated nerve preparation. Treatment Response time / ms Response occurred? None (control) 21 yes Substance X — blocks neurotransmitter release — no Substance Y — blocks receptors on the next neurone — no Substance Z — slows the breakdown of neurotransmitter 19 yes, but prolonged (a)
(1)Give
Give the two substances in Table 1 that stopped the response completely.
Table 1 — the effect of three substances on the time taken for a reflex response in an isolated nerve preparation. Treatment Response time / ms Response occurred? None (control) 21 yes Substance X — blocks neurotransmitter release — no Substance Y — blocks receptors on the next neurone — no Substance Z — slows the breakdown of neurotransmitter 19 yes, but prolonged (b)
(3)Explain
Explain why substances X and Y both stop the response, even though they act at different points.
Table 1 — the effect of three substances on the time taken for a reflex response in an isolated nerve preparation. Treatment Response time / ms Response occurred? None (control) 21 yes Substance X — blocks neurotransmitter release — no Substance Y — blocks receptors on the next neurone — no Substance Z — slows the breakdown of neurotransmitter 19 yes, but prolonged (c)
(2)Suggest
Suggest why the response with substance Z was prolonged.
Table 1 — the effect of three substances on the time taken for a reflex response in an isolated nerve preparation. Treatment Response time / ms Response occurred? None (control) 21 yes Substance X — blocks neurotransmitter release — no Substance Y — blocks receptors on the next neurone — no Substance Z — slows the breakdown of neurotransmitter 19 yes, but prolonged (Total for Question 1 = 6 marks)
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(1)Which
Which of these crosses the gap at a synapse?
Answer A an electrical impulse B a neurotransmitter C a hormone D an enzyme (Total for Question 2 = 1 mark)
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(1)Name
Name the type of neurone that carries an impulse from the central nervous system to a muscle.
Figure 1 — the reflex arc that withdraws a hand from a sharp object. (Total for Question 3 = 1 mark)
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(1)Give
Give one advantage to an animal of a reflex action being automatic.
(Total for Question 4 = 1 mark)
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(4)Describe
Describe the reflex arc that pulls a hand away from a sharp object.
Figure 1 — the reflex arc that withdraws a hand from a sharp object. (Total for Question 5 = 4 marks)
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(3)Explain
Explain how an impulse is passed from one neurone to the next at a synapse.
(Total for Question 6 = 3 marks)
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(2)Explain
Explain why an impulse can travel in one direction only across a synapse.
(Total for Question 7 = 2 marks)
Have them marked, then defend the answer
Practice tells you the mark; teaching it back tells you whether you understand it. On Incandio a topic counts as mastered only once you have taught it and defended it.
- Mark these questions — 9 questions, marked on Incandio against the authored scheme, with the mistake you actually made named.
- Teach it — explain Synapses and the Reflex Arc to Ember, an AI pupil who does not have it yet and asks the awkward question.
- Defend it — argue it against Santiago Ramón y Cajal over three rounds, marked against descriptors you can read first.
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Back to the lesson
- Synapses and the Reflex Arc — Neurones do not touch. What crosses the gap between them, why the gap is there at all, and how a hand leaves a hot pan before you know it was hot.
- All of Incandio Biology · Incandio Exam Practice