<strong>What is photosynthesis and how does it occur?</strong>
Some science concepts can be challenging to understand for school-goers if taught only theoretically. Lofty texts usually contain all the information, but more often than not, it is a task for kids to digest it properly. Here is a simple, to-the-point explanation of the process of photosynthesis, which we are sure your kid will pick up easily.
Fundamentally, photosynthesis is the process that releases the oxygen that is essential for our survival. Plants, algae and certain bacteria participate in this process by turning sunlight, carbon dioxide (CO2) and water into food and oxygen.
Most plants contain several exclusive pigments which allow them to absorb light energy from the sun. One of these fundamental pigments is chlorophyll, which is also responsible for giving plants their green colour. For doing so, it absorbs red and blue light which it subsequently reflects as green light. It is quite a large molecule and is not produced easily. It only starts breaking down towards the end of a plant’s life. The process of photosynthesis occurs in chloroplasts which are mitochondria-type structures found in plants.
A plant first absorbs light energy from the sun which it converts into chemical energy. As soon as a photon of light reaches the reaction centre in the plant, chlorophyll or a similar pigment molecule produces an electron. This electron escapes the plant body by travelling through an electron transport chain. The chain is responsible for generating the energy which is required to produce a source of chemical energy for cells known as adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH.) After this, the leftover ‘electron hole’ (where the electron initially escaped from) is filled once again by using an electron from water. Oxygen is released into the atmosphere as a result of the splitting of water molecules.
Quick experiment to demonstrate photosynthesis
This simple DIY photosynthesis experiment will make understanding photosynthesis a breeze.
What you will need
- A large glass bowl
- Lukewarm water
- A big green leaf
- A rock
Step-by-step guide to perform this experiment
- Fill ¾ of the glass bowl with lukewarm water.
- Place a fresh green leaf in the water. To ensure that it stays put, use the small rock to keep it submerged.
- Place the bowl in a sunny spot and wait for 2-3 hours.
- After the time has passed, observed the leaf and the bowl.
What is happening here?
It will be observed that there are small bubbles forming on the leaf as well as on the edges of the bowl. Here, the leaf is using the process of photosynthesis to convert sunlight into energy. While doing so, it releases the extra oxygen it produces in the form of the bubbles. These bubbles rise to the surface as a consequence of oxygen being lighter than water.