Experiment to investigate the effect of light on the organic plant elodea.

Authors Avatar

Experiment to investigate the effect of light on the organic plant elodea.

Aim: To calculate the rate of photosynthesis from the number of oxygen bubbles produced by the plant.

Photosynthesis: The process by which green plants use the sun’s energy to build up carbohydrate reserves.

Plants make their own organic food such as starch. Plants need Carbon dioxide, water, light and chlorophyll in order to make food; and starch and oxygen are produced. Carbon dioxide and water are the raw materials of photosynthesis.

The equation of photosynthesis is:

6CO2        +  6H20       ⇒   C6H12O6  +   6O2

        Carbon dioxide  +      water                     glucose              +    oxygen

Green plants need sunlight. They use the light energy to make a sugar called glucose.

Glucose can be turned into another type of sugar called sucrose and carried to other parts of the plant in phloem vessels. Glucose can also be turned into starch and stored. Both starch and sucrose can be converted back into glucose and used in respiration.

Photosynthesis happens in the mesophyll cell of leaves. There are two kinds of mesophyll cells – palisade mesophyll and spongy mesophyll. The mesophyll cells contain tiny bodies called chloroplasts which contain a green chemical called chlorophyll. This chemical is used to catch the light energy needed in photosynthesis.

Join now!

They take carbon dioxide from the air. Plants use sunlight to turn water and carbon dioxide into glucose. Plants use glucose as food for energy and as a building block for growing. The way plants turn water and carbon dioxide  into sugar is called photosynthesis. That means “putting together with light”

During the winter, there is not enough light or water for photosynthesis. The green chlorophyll disappears from the leaves. All plants need light in order to photosynthesise. Photosynthesis can only occur ...

This is a preview of the whole essay