Final answer:
Answer: a. Oxidation of RH and reduction of NAD+. RH is the reducing agent that donates electrons (oxidized), while NAD+ is the oxidizing agent that accepts electrons (reduced), essential in metabolism as NAD+ functions as a pivotal electron carrier.
Step-by-step explanation:
The correct statement that explains how electrons are transferred and the role of each species in the equation RH + NAD+ → NADH + R is 'a. Oxidation of RH and reduction of NAD+'. Here, RH acts as a reducing agent, meaning it donates electrons, and NAD+ acts as an oxidizing agent, meaning it accepts electrons. When RH donates an electron, it gets oxidized to R, and when NAD+ accepts an electron, it gets reduced to NADH. This type of reaction is essential in biological systems, particularly in the context of metabolism where NAD+ is a common electron carrier used in catabolism.
The process can be understood in the context of redox reactions, where oxidation and reduction occur simultaneously; a molecule loses electrons through oxidation while another gains electrons through reduction. In living organisms, these reactions are important for the transfer of energy. NAD+ serves as a key coenzyme in these redox reactions, facilitating energy production within cells by undergoing reversible reduction and oxidation.