Answer:
B (ATP and NADPH)
Explanation:
The photosynthetic cycle occurs in two stages: the light-dependent stage and the light-independent stage.
The main purpose of the light stage is to create energy (ATP) that the cell needs to assemble carbon into sugar.
The light stage occurs when a photon of light strikes an electron in the chlorophyll molecule. The chlorophyll (Photosystems I and I) becomes positively charged and hence, activated by raising electrons to a higher energy level.
Electrons from these chemically activated chlorophyll molecules, which are positively charged, split water molecules into protons (H+), and electrons (OH-). This splitting process is called PHOTOLYSIS OF WATER. The electrons return to chlorophyll (Photosystem I), deactivating it. The proton(H+) and electron are received by an hydrogen acceptor molecule (NADP+) to produce NADPH (electron carriers) and oxygen release. As protons (H+) pass along the gradient, the proton pump starts to work. The energy of passing protons (accumulated in the thylakoid) allows the synthesis of ATP from Adenosine diphosphate (ADP) and Pi (inorganic phosphate).
In a nutshell, the light stage starts with light, water, NADP+, ADP and results in an accumulation of energy(ATP) and electron carriers (NADPH) with a release of oxygen which is a kind of exhaust gas.
It is important to note that the produced ATP and NADPH are used to power and reduce the CO2 molecule to produce sugar in the enzymatic or light-independent stage.
