Question

Describe the three chemical changes that occur during the light-dependent reactions.

Answer 1

Answer:

1. it uses light energy to make two molecules needed for the next stage of photosynthesis
2. light energy is captured by plant,it then converted to chemical energy.

Explanation:

, I

Answer 2

Answer:

1. Light energy is transformed into chemical energy.
2. ADP is transformed into ATP
3. NADP is transformed into NADP2

Explanation:

Within the chloroplast, more precisely in the tilacoids, are the chlorophyll molecules and other pigments, which are organized in so-called photosystems. These consist of a complex antenna and a reaction center. In the complex antenna, the light energy is captured and transferred to the reaction center, which converts this energy into chemical energy.

There are two photosystems, I and II, which are linked through an electron transport chain. Each of the photosystems has a pair of different chlorophyll molecules: in I, there is the pair known as P700, and in II, the P680.

The first step in transduction reactions is the absorption of light energy by the complex antenna of photosystem II. This captured energy is then transferred to the chlorophyll P680 molecule at the reaction center. The energized electrons are transferred from the reaction center to an electron receptor. The removed electrons are replaced by low energy electrons from the photolysis process.

The energized electrons descend to photosystem I via an electron transport chain. During this passage, ATP is produced from ADP and phosphate, a process known as photophosphorylation.

At the same time, water molecules - when struck by sunlight - are "broken" (the term "water photolysis" is used to mean the breakdown of water molecules) and release protons (H +), electrons (e-) and oxygen molecules. Protons are captured by NADP molecules, which convert to NADPH2; oxygen molecules are released into the medium; and the electrons return to chlorophyll, replacing those it lost at the beginning of the process.