To test for photosynthesis, we can conduct an experiment using a plant, light, and a substance that indicates the presence of carbon dioxide. Here is a step-by-step procedure for the experiment:

1. Choose a healthy green plant with leaves that are exposed to sunlight. This could be a potted plant or a leaf from an outdoor plant.

2. Place the plant in a container or a beaker filled with water. Ensure that the leaves are fully submerged in the water.

3. Cover the container with a transparent plastic bag, leaving a small opening for air circulation.

4. Place the container in a well-lit area where the plant can receive sunlight.

5. After a few hours, carefully remove the plant from the water and cut off a leaf. This leaf will be used for testing.

6. Take a test tube and fill it with a solution that contains an indicator for carbon dioxide, such as bromothymol blue. This indicator changes color in the presence of carbon dioxide.

7. Insert the leaf into the test tube, making sure it is fully submerged in the solution.

8. Observe the test tube for any color change. If the solution turns yellow or green, it indicates the presence of carbon dioxide, which means that photosynthesis has occurred.


Photosynthesis is a vital process that occurs in the leaves of plants and plays a crucial role in the survival of plants and the production of oxygen. Here are the key points explaining the function of leaves in photosynthesis:

- Chloroplasts: Leaves contain specialized structures called chloroplasts, which contain a pigment called chlorophyll. Chlorophyll absorbs light energy from the sun, which is essential for photosynthesis.

- Carbon Dioxide Absorption: Through tiny openings called stomata on the surface of leaves, plants absorb carbon dioxide from the atmosphere. Carbon dioxide is a crucial ingredient for photosynthesis.

- Water Uptake: Leaves also have a network of veins that transport water from the roots to the leaves. This water is used in photosynthesis along with carbon dioxide and light energy.

- Conversion of Energy: During photosynthesis, chlorophyll in the chloroplasts captures light energy. This energy is then converted into chemical energy in the form of glucose, a sugar molecule.

- Release of Oxygen: As a byproduct of photosynthesis, oxygen is released into the atmosphere through the stomata. This oxygen is vital for the survival of living organisms, including humans.

- Food Production: Glucose produced during photosynthesis is used by plants as a source of energy for various cellular activities. It is also stored as starch in different parts of the plant, including the leaves.

In conclusion, leaves play a crucial role in the process of photosynthesis. They capture light energy, absorb carbon dioxide, and release oxygen, while also producing glucose for energy storage. By conducting a test for photosynthesis, we can observe the occurrence of this essential process in plants.