AP BIOLOGY

Detailed explanation-1: -In the light-dependent reactions, energy absorbed by sunlight is stored by two types of energy-carrier molecules: ATP and NADPH. The energy that these molecules carry is stored in a bond that holds a single atom to the molecule. For ATP, it is a phosphate atom, and for NADPH, it is a hydrogen atom.

Detailed explanation-2: -The light-dependent reactions use light energy to make two molecules needed for the next stage of photosynthesis: the energy storage molecule ATP and the reduced electron carrier NADPH.

Detailed explanation-3: -The light-dependent reaction is a photochemical reaction taking place in the thylakoid membranes of chloroplasts, where light energy is transformed into adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH).

Detailed explanation-4: -ATP and NADPH are produced in the light reaction of photosynthesis. These are used in the biosynthetic pathway. There are also used in the Calvin cycle to reduce carbon dioxide. During that process, the carbon dioxide is reduced to sugar.

Detailed explanation-5: -Section Summary. Using the energy carriers formed in the first steps of photosynthesis, the light-independent reactions, or the Calvin cycle, take in CO2 from the environment. An enzyme, RuBisCO, catalyzes a reaction with CO2 and another molecule, RuBP.