Question

What is common in NAD, ATP and FMN?
A. Zn
B. P
C. Ca
D. Mg

Answer 1

Hint: A cofactor central to metabolism is called nicotinamide adenine dinucleotide (NAD). Adenosine triphosphate (ATP) is a nucleotide which is a coenzyme used in cells. It is also termed as the "molecular unit of currency" in the process of metabolism. ATP carries chemical energy within cells. FMN is a Flavin mononucleotide.

Complete answer: A phosphate is an anion, salt, functional or ester group derived from the phosphoric acid. Orthophosphate, a derivative of orthophosphoric acid, is widely used. Cells use a molecule called Adenosine Triphosphate (or ATP) as a source of energy. The phosphate in this molecule supplies the energy of the substrate in our cells. Enzymes exist in our cells that can extract phosphate from ATP and bind it to a different molecule, normally a protein. NAD and NADP are two of the most significant coenzymes in the cell. NADP is essentially a NAD with a third group of phosphates attached. Nicotinamide adenine dinucleotide is involved in many redox reactions in cells, including those in glycolysis and most of those in the citric acid cycle of cellular respiration. In biological systems, FAD serves as an acceptor of hydrogen ion and electron in its entirely oxidized form, an acceptor or donor in the form of FADH, and a donor in the reduced form of FADH2. NAD, FMN and ATP molecules serve as coenzymes that are oxidized by the acceptance of electrons from substrates. NAD has 2 phosphate molecules, ATP has 3 phosphate molecules, and FMN has one phosphate in position 5. ‘P’ is popular in NAD, ATP and FMN.
Hence, option B is the correct answer.

Note: Phosphorus can be used in biological systems as free phosphate anions bound to organic molecules or solution (inorganic phosphate) as various organophosphates. Organic phosphates are usually found in the form of esters such as nucleotides. Examples of such nucleotides are AMP, ADP, and ATP and DNA and RNA.