Respiration is a cellular process that produces ATP - Scottish Highers Biology - Question 9 - 2019

In Step 1, ATP plays a crucial role by phosphorylating glucose or its intermediates. This phosphorylation helps to activate glucose, making it more reactive as it enters subsequent steps of glycolysis.

Glycolysis results in a net gain of ATP because a total of 4 ATP molecules are produced, while only 2 ATP molecules are consumed during the process. Therefore, the net gain is 2 ATP molecules after accounting for the input and output.

Dehydrogenase enzymes play a vital role in glycolysis by removing hydrogen ions and electrons from intermediates. They pass these electrons to the coenzyme NAD, converting NAD to NADH, which is essential for the continued energy production in the cell.

The conditions required for fermentation include the absence of oxygen, which forces the cellular pathways to shift to anaerobic respiration.

The conversion of pyruvate to lactate is essential for glycolysis because it regenerates NAD from NADH. This regeneration of NAD is crucial, as it allows glycolysis to continue producing ATP under anaerobic conditions by ensuring there is a sufficient supply of NAD for the process.