This is a response post to classmate Danielle 

Her Post:

1. Briefly explain the light-dependent reactions of photosynthesis: where does this take place, what are the reactants and what is produced? Whenever light energy is absorbed by pigments in leaves, they are transformed to a diverse form of light energy and chemical energy. During the first stage of photosynthesis light energy is converted to chemical energy. This requires a series of organic reactions known as the light-dependent reactions. The light-dependent reaction of photosynthesis depends on light energy to form two types molecules needed for the next step of photosynthesis. The ATP is the energy storage molecule and the NADPH it’s the reduced electron carrier. “ATP is produced from ADP (adenosine diphosphate) and phosphate by several exergonic reactions in cells, but the main sources of ATP are the major energy reactions: photosynthesis and respiration (lecture).” The light reaction occurs in the location of the thylakoid membrane. The reactants of light-dependent reactions the sunlight and water to which processes it into the product of ATP, NADPH and Oxygen.
2. Briefly explain the light-independent reactions of photosynthesis: where does this take place, what are the reactants and what is produced? How do plants store excess product from these reactions?

Unlike the light dependent reaction light dependent reaction is not driven by light; it occurs whether light is present or not. It also involves the Calvin cycle. These reactions transpire in the stroma, which is the liquid-filled interior part of a chloroplast that is exterior to the thylakoid membranes. The reactants of the Calvin Cycle use ATP, NADPH and Carbon dioxide. The end product from which the reactants of the light independent produce is glucose. “Plants store the excess product in bonds of sugar molecules. They normally make more than needed and store the energy to later use as fuel. A good example is starch in potatoes (Simon, Dickey and Reece 2013, 93).”

1. Where does the energy come from that allow plants to synthesize the necessary biological macromolecules that allow it to grow? Hint: It is NOT from sunlight. Explain your answer.

The energy that plants uses to grow is called glucose; which is produced through photosynthesis. This is synthesized through the process of photosynthesis where plants use carbon dioxide and water to produce oxygen.  

References

Simon, E.J., Dickey, J.L., & Reece, J.B. (2019). Campbell essential biology: 7th Edition. Pearson Education Inc

Light-dependent reactions (photosynthesis reaction) (article). (n.d.). Retrieved January 20, 2021, from https://www.khanacademy.org/science/ap-biology/cellular-energetics/photosynthesis/a/light-dependent-reactions#:~:text=The%20light%2Ddependent%20reactions%20use,membranes%20of%20organelles%20called%20chloroplasts (Links to an external site.).

Edited by Daneille Bryan on Jan 20 at 1:46am Reply