Amolecule, such as nadh, is when it donates an electron, and it also loses energy because this is an reaction. the molecule simultaneously gaining this electron is and gains energy because this is an reaction. these electron transferring reactions are called reactions, and they are required for cellular respiration and photosynthesis.

answer:

see the answer and explanation below,

explanation:

a molecule, like nadh, is giver / donor when it donates an electron, and it also loses energy because this is a reaction the molecule that simultaneously gains this electron is and gains energy because this is a reaction these electron transfer reactions are called reactions, and are necessary for cellular respiration and photosynthesis.

in the reactions of oxide reduction (redox) one substance is reduced and another is oxidized. this type of reaction occurs in diverse biological reactions.

in cellular respiration, the reduction of nad (nicotinamide adenine dinucleotide) to nadh and oxidation of nadh to nad occurs.

in photosynthesis, c02 is reduced by forming sugars, using light energy.

it's c. elements are placed in rows based on how may valencies electrons have.