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Biology journal Cambridge IGCSE 0610

How plants make food · 3 parts · syllabus 6.1

What does a leaf need to make starch?

See how a leaf uses energy from light to make glucose from carbon dioxide and water, then test leaves for starch to find out what a leaf needs, and follow where the sugar goes.

Start learning Explore the experiment
A basil plant in a terracotta pot on a sunny kitchen windowsill, with a few cut sprigs on a saucer beside it. (enlarge)

Follow the idea

  1. What photosynthesis makes

    Glucose and oxygen from carbon dioxide and water, using energy from light, with chlorophyll in the chloroplasts

    Not started

  2. What a leaf needs: the starch investigation

    The starch test, destarched plants and controls for light, chlorophyll and carbon dioxide

    Not started

  3. What the plant does with its sugar

    Starch, cellulose, respiration, sucrose and nectar; nitrate and magnesium ions

    Not started
A bench with two potted plants: one with a foil strip round a leaf and two leaves sealed in clear bags, one bag with a dish of white granules and one with an empty dish; the other plant has leaves with green middles and cream edges. In front: forceps on a white tile, an amber dropper bottle, a beaker of water, and a boiling tube standing in a beaker of hot water on a hotplate.

The experiment · Two destarched plants · a foil strip, a variegated leaf and two sealed bags · the starch test with iodine

Run it yourself, or project it for the class

Use the apparatus step by step and look closely at what happens. The whole experiment fits one screen, so it works on a projector too.

Open the experiment