Question 1
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanWhich part of a plant is a source of sucrose?
- a developing fruit
- a growing root tip
- a fully grown green leaf
- a young bud
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Answer: C (1)
Question 2
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanDefine the term translocation.
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- movement of sucrose and amino acids (1)
- in the phloem (1)
- from sources to sinks (1)
Question 3
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanDescribe what is meant by a source and a sink in a plant. Give one example of each.
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- source: part of the plant that releases sucrose / amino acids (1)
- example: mature / green leaf (1) allow storage organ when new shoots are growing
- sink: part of the plant that uses or stores sucrose / amino acids (1)
- example: growing root tip / shoot tip / fruit / seed / storage organ (1)
Question 4
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanA potato tuber stores carbohydrate as starch during the summer. In spring, the tuber grows new shoots and sucrose from the tuber is moved to them. Explain why the tuber is a sink in summer and a source in spring.
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- in summer it receives sucrose and stores it (as starch) (1)
- so it is a sink (1)
- in spring (starch is broken down and) sucrose is released (1)
- which moves to the growing shoots, so it is a source (1)