In which tissue does translocation happen?

phloem. Phloem carries dissolved food.

where sucrose is made or released. Leaves are the main source.

In what form is sugar carried in the phloem?

sucrose. Glucose is converted to sucrose for transport.

a growing fruit. A fruit takes in sugar and stores it.

What else is carried in the phloem besides sucrose?

amino acids. They are needed to make proteins in growing parts.

Translocation · Cambridge IGCSE Co-ordinated Sciences (9

In plain words

The sugar a plant makes in its leaves is needed everywhere: in the roots, in growing shoots, in fruit. Translocation is the delivery service that carries it there, through the phloem.

Three things to know

Translocation is the movement of sucrose and amino acids in the phloem, from sources to sinks.
A source is where they are made or released, usually the leaves. A sink is where they are used or stored: roots, fruits, growing buds.
A part of a plant can be a sink at one time of year and a source at another: a potato stores starch in summer and releases sugar to grow new shoots in spring.

Tips and tricks

Sugar travels as sucrose, not glucose, and it is stored as starch.
Sources and sinks can swap. Give the potato as your example.

5 questions, about 2 minutes.

It lands in your notebook with its questions as flashcards.

Translocation: 5 questions and answers

These are the quiz’s questions. Do the quiz first, then come back here for the ones that got you.

In which tissue does translocation happen?
- xylem
- phloem (the answer)
- epidermis
- cuticle
Phloem carries dissolved food.
What is a source?
- where sucrose is used
- where sucrose is made or released (the answer)
- a root hair
- a stoma
Leaves are the main source.
In what form is sugar carried in the phloem?
- glucose
- starch
- sucrose (the answer)
- cellulose
Glucose is converted to sucrose for transport.
Which is a sink?
- a mature leaf in sunlight
- a growing fruit (the answer)
- the cuticle
- a stoma
A fruit takes in sugar and stores it.
What else is carried in the phloem besides sucrose?
- oxygen
- water vapour
- amino acids (the answer)
- carbon dioxide
They are needed to make proteins in growing parts.

5 questions

Tap an answer and you’ll see straight away whether it’s right, and why.

Worksheet

3 questions, 6 marks. Write your answers on paper, then check them.

Translocation

Cambridge IGCSE Co-ordinated Sciences (9–1) 0973 · 6 marks · papermunch.org

Name ______________________________ Date ______________

State what is meant by translocation.[2]
Show answerHide answer
The movement of sucrose and amino acids in the phloem, from sources to sinks.
I got this one
Give one example of a source and one example of a sink in a plant in summer.[2]
Show answerHide answer
Source: a leaf. Sink: any one of a root, a fruit, a growing shoot tip, a storage organ such as a tuber.
I got this one
Explain why a potato tuber is a sink in summer and a source in spring.[2]
Show answerHide answer
In summer it receives sucrose from the leaves and stores it as starch. In spring the starch is broken down and the sugar is carried to the new shoots.
I got this one

Answers: Translocation

1. The movement of sucrose and amino acids in the phloem, from sources to sinks.
2. Source: a leaf. Sink: any one of a root, a fruit, a growing shoot tip, a storage organ such as a tuber.
3. In summer it receives sucrose from the leaves and stores it as starch. In spring the starch is broken down and the sugar is carried to the new shoots.