Question

explain the role of Photosynthesis in trapping solar energy and its conversion ​

Answer 1

Photosynthesis is the process by which plants produce oxygen and energy in the form of sugar by combining sunlight, water, and carbon dioxide.

• Plants, algae, and some bacteria engage in photosynthesis, which captures energy from the sun to produce oxygen (O2) and chemical energy stored in glucose (a sugar).
• Plants take in carbon dioxide (CO2) and water (H2O) from the air and soil during photosynthesis.
• Water is oxidised in the plant cell, which means it loses electrons, but carbon dioxide is reduced, which means it receives electrons.
• Water is converted to oxygen, while carbon dioxide is converted to glucose.
• The plant then releases the oxygen into the atmosphere while storing energy in the glucose molecules.
• Small organelles called chloroplasts store the energy of sunlight inside the plant cell.
• Chlorophyll, a light-absorbing pigment found within the chloroplast's thylakoid membranes, is responsible for the plant's green colour.
• Chlorophyll absorbs energy from blue and red light waves during photosynthesis and reflects green light waves, giving the plant its green colour.
• The light-dependent process occurs within the thylakoid membrane and requires a constant influx of sunshine to occur, hence the name.
• The chlorophyll collects energy from light wavelengths and converts it into chemical energy in the form of ATP and NADPH molecules.
• The Calvin Cycle, also known as the light-independent stage, occurs in the stroma, the area between the thylakoid and chloroplast membranes, and does not require light directly to perform.
• Energy from the ATP and NADPH molecules is utilised to construct carbohydrate molecules, such as glucose, from carbon dioxide at this cycle.