Energy in ___ is absorbed by an electron in a photocenter. This energy is converted from light energy into chemical energy into kenetic energy as the energized electron is used in back to back REDOX reaction in the electron transport chain, ETC. The ETC creates ___ which is used by the cell to power the formation of ATP. In ___ (cyclic or noncylcic) the electron returns to the photocenter. In ___ (cyclic or non-cyclic) photosynthesis the electron reduces NADP+ to form ___.

Explanation:

Energy in _SUNLIGHT__ is absorbed by an electron in a photocenter. This energy is converted from light energy into chemical energy into kinetic energy as the energized electron is used in back to back REDOX reaction in the electron transport chain, ETC. The ETC creates _AN ENERGY GRADIENT__ which is used by the cell to power the formation of ATP. In _CYCLIC PHOSPHORYLATION__ (cyclic or noncylcic) the electron returns to the photocenter. In _NON-CYCLIC PHOSPHORYLATION__ (cyclic or non-cyclic), the electron reduces NADP+ to form _NADPH__.

Photophosporylation is the process of using light (photo) to produce ATP from ADP (phosphorylation i.e. addition of phosphorous). There are two types: cyclic and non-cyclic phosphorylation.

In non-cyclic phosphorylation, there are two photosystems (photocenter) involved, and electron is passed to NADP+.

In cyclic phosphorylation,  one photosystem is involved and the electron is not transferred to NADP+, it is circled back to the photosytem.

The reduced form of NADP+ is NADPH. (Remember that: reduction is defined as the addition of hydrogen)

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."