AP BIOLOGY

Detailed explanation-1: -The light reactions provide energy to fuel the carbon reactions to produce carbohydrates. Biologists consider photosynthesis to be the most important metabolic process because without it, there would be no CO 2 in the atmosphere.

Detailed explanation-2: -During the light reactions, the energy from sunlight is stored in energy carrier molecules. These energy carrier molecules are then used to power the reactions of the Calvin cycle, where CO2 molecules are joined together to produce carbohydrates such as glucose.

Detailed explanation-3: -The carbon atoms used to build carbohydrate molecules comes from carbon dioxide, the gas that animals exhale with each breath. The Calvin cycle is the term used for the reactions of photosynthesis that use the energy stored by the light-dependent reactions to form glucose and other carbohydrate molecules.

Detailed explanation-4: -Photosynthesis absorbs light energy to build carbohydrates in chloroplasts, and aerobic cellular respiration releases energy by using oxygen to metabolize carbohydrates in the cytoplasm and mitochondria. Both processes use electron transport chains to capture the energy necessary to drive other reactions.

Detailed explanation-5: -The light reactions use ATP as their energy source. The light reactions use sunlight as their energy source. The carbon reactions produce ATP and NADPH. When chlorophyll a absorbs light, electrons are “excited” and ejected from the chlorophyll a molecule.