Light Reactions of Photosynthesis

Home/Light Reactions of Photosynthesis
Light Reactions of Photosynthesis 2018-07-21T15:28:52+00:00

Photosynthesis takes place in the organelle of the plant cell known as the chloroplasts.

Chloroplasts are one of the main differences between plant and animal cells. Animal cells do not have chloroplasts, so they cannot photosynthesize. Photosynthesis occurs in two stages.
During the first stage, the energy from sunlight is absorbed by the chloroplast. Water is used, and oxygen is produced during this part of the process.

During the second stage, carbon dioxide is used, and glucose is produced.

Chloroplasts contain stacks of thylakoids, which are flattened sacs of membrane. Energy from sunlight is absorbed by the pigment chlorophyll in the thylakoid membrane.

The reactants of photosynthesis are carbon dioxide and water. These are the molecules necessary to begin the process. But one more item is necessary, and that is sunlight.

*Chlorophyll is the green pigment in leaves that captures energy from the sun. Chlorophyll molecules are located in the thylakoid membranes inside chloroplasts.

*The veins in a plant carry water from the roots to the leaves.

*Carbon dioxide enters the leaf from the air through special openings called stomata

The Products:-
The products of photosynthesis are glucose and oxygen. This means they are produced at the end of photosynthesis. Glucose, the food of plants, can be used to store energy in the form of large carbohydrate molecules.

The Light Reactions
Photosynthesis begins with the light reactions. It is during these reactions that the energy from sunlight is absorbed by the pigment chlorophyll in the thylakoid membranes of the chloroplast. The energy is then temporarily transferred to two molecules, ATP and NADPH, which are used in the second stage of photosynthesis.

Summary
Photosynthesis occurs in the chloroplast of the plant cell.
Carbon dioxide, water, and the sun’s energy are necessary for the chemical reactions of photosynthesis.
The products of photosynthesis are glucose and oxygen.

 

PiRuby is the perfect Tool to Discover Educational Content from Textbooks. Learning and Excellence Made Easy… Really Easy!