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Algal Balls - Photosynthesis Using Algae Wrapped in Jelly Balls

This reliable practical allows students to use algae to look at the rate of photosynthesis with quantifiable and replicable results. In this protocol, the green alga Scenedesmus quadricauda is immobilised in alginate beads. Changes in the colour of hydrogen carbonate indicator solution (also called bicarbonate indicator) can then be used to investigate the rate of photosynthesis under different environmental conditions.

The immobilised algae can be used to demonstrate or investigate:

1. Photosynthesis only proceeds in the light

2. Light intensity affects the rate of photosynthesis

3. The compensation point between photosynthesis and respiration

4. Wavelength (colour of light) affects the rate of photosynthesis

5. Concentration of algae will affect the rate of photosynthesis.



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Photosynthesis, POSTED BY
Plant science, POSTED BY
cell division, POSTED BY