Question

In hexose monophosphate shunt, the net formation of ATP molecules is
(a)36
(b)35
(c)38
(d)34

Answer 1

Hexose monophosphate shunt is an alternative pathway for glucose oxidation to glycolysis or the tricarboxylic acid cycle. Six hexose monophosphate shunting glucose molecules contain $NADP{ H }_{ 2 }$ and 6 carbon dioxide. 3ATP generates one $NADP{ H }_{ 2 }$. Also, one ATP molecule is used for the initial glucose phosphorylation.

Complete answer:
In the cytoplasm, the hexose monophosphate shunt pathway occurs and has two stages; the oxidative and non-oxidative stages. This is the only process that generates reduced $NADP{ H }_{ 2 }$ which acts in the biosynthetic processes as the reduction agent. 12 Molecules of $NADP{ H }_{ 2 }$ form 36 ATP molecules while undergoing ETS. At the beginning, one ATP is consumed which results in the net formation of 35 ATP molecules.

Additional Information: Two molecules of $NAD{ P }^{ + }$ are reduced to NADPH in the oxidative step, using the energy from converting glucose-6-phosphate into ribulose-5-phosphate. Then these NADPH molecules can be used in the cell as an energy source.
The non-oxidative step creates 5-carbon sugars, which can be used in nucleotide synthesis, nucleic acids, and amino acids.
So, the correct option is, '35'.

Note: The shunting of hexose monophosphate, also known as the pentose phosphate pathway, is a special process used for many purposes to produce products that are important in the body. The HMP shunt is used to manufacture nicotinamide adenine dinucleotide phosphate (NADPH) and ribose-5-phosphate. The HMP shunt also has importance in the medical field, as defects in the enzyme or cofactor can have potentially fatal effects for the patients affected.