# How much is the net gain of ATP in glycolysis?

What is the net gain of ATP molecules per glucose in glycolysis? Explanation: The net gain of ATP molecules in glycolysis is 2. The process requires two ATP molecules per glucose molecule to begin, and eventually four ATP molecules per glucose molecule are created. Therefore, the net gain of ATP molecules per glucose in glycolysis is 2 - 2 = 0.

Glycolysis is the first step in cellular metabolism generating energy for cells from glucose. It occurs in all living cells and is an important part of cell metabolism. As a result of glycolysis, two pyruvate molecules and two hydrogen ions are generated per glucose molecule. These can then enter into the TCA cycle or be converted into ethanol or lactic acid depending on the needs of the cell.

During glycolysis, two ATP are consumed to generate two pyruvate molecules and two NADH molecules (hydrogen atoms with a negative charge). One ATP is also used to split off one water molecule. Thus, two ATP are used up in glycolysis to generate two molecules of pyruvate plus two molecules of NADH + H+. This equation shows that two ATP are used up in glycolysis to generate five molecules of ADP + five molecules of Pi - two molecules of pyruvate plus two molecules of NADH.

## What is the net gain of ATP during the aerobic respiration of one glucose molecule?

During the aerobic respiration of one molecule of glucose, there is a net gain of 38 ATP molecules. However, most eukaryotic cells require two molecules of ATP to transfer the NADH created during glycolysis into the mitochondrion for further oxidation. As a result, the net ATP gain in this case is 36 molecules. It should be noted that under anaerobic conditions, where no oxygen is present and thus no oxidative phosphorylation can take place, yeast and other organisms still generate small amounts of energy (adenosine triphosphate, or ATP) through an anaerobic pathway.

In prokaryotes such as bacteria, which do not have mitochondria, the entire process takes place in membrane-bound compartments called peroxisomes. The overall reaction is very similar to that of aerobic respiration in eukaryotes, but instead of generating ATP the process generates reduced coenzymes such as NADH and FADH. The electron transport chain within the peroxisome uses these cofactors to reduce hydrogen peroxide and other reactive oxygen species produced by bacterial metabolism. Proteins with high-energy phosphate groups are also used up in this process, so it requires more energy than simple carbohydrate fermentation. Therefore, we can say that under anaerobic conditions, bacteria use up nutrients (such as sugar) and produce energy (in the form of ATP).

## What requires an investment of 2 ATP?

Energy in the form of two ATP molecules is required in the first part of glycolysis to convert glucose into two three-carbon molecules. This process requires oxygen as well as a source of hydrogen ions (H+). The only chemical reaction that produces these ions is oxidation-reduction reactions, which occur between metals and organic compounds or within organic compounds themselves. Thus, an organism must have access to metal atoms as well as carbon and hydrogen atoms in order to carry out glycolysis.

In organisms that use oxygen for respiration, the reduction of oxygen requires electrons donated by redox enzymes. These enzymes contain iron-sulfur centers with low molecular weights that can be reduced by hydrogen ions. Therefore, iron-, sulfur-, and magnesium-containing compounds are necessary ingredients in aerobic metabolism. Iron is essential because it forms parts of many proteins involved in energy production processes. Sulfur is also needed because all sulfhydryl groups (-SH) in proteins require reducing agents such as glutathione or NADPH to keep them from being modified by oxidants such as oxygen radicals. Magnesium is important because it acts as a cofactor for many enzymes involved in energy production pathways. Energy is released during this process and used by cells to function properly. This energy is then converted back into glucose so that the process can continue indefinitely.

## How do you calculate ATP from glucose?

Glucose is broken down into pyruvate and energy during glycolysis, yielding a total of 2 ATP (Glucose + 2 NAD+ + 2 ADP + 2 Pi = 2 Pyruvate + 2 NADH + 2 H+ + 2 ATP + 2 H2O). The hydrogen ions that are released during this process can be used to generate electricity by using the enzyme hydrogenase.

Thus, the overall reaction for glucose metabolism is: Glucose + 2 NAD+ + 2 ADP + 2 Pi -> 2 Pyruvate + 2 NADH + 2 H+ + 2 ATP + 2 H2O.

ATP is also generated through substrate level phosphorylation, in which glucose yields two molecules of 3-phosphoglycerate plus two molecules of ATP. This reaction is catalyzed by glycogen synthase kinase-3 (GSK-3) and occurs in liver cells before bedtime. GSK-3 is inhibited after bedtime when blood glucose levels drop, allowing it to convert most of the remaining glycogen into glucose rather than storing it as fat.

Finally, some ATP is also generated through the degradation of fats and proteins via enzymes called oxidases and dehydrogenases. Proteins are mainly composed of amino acids that are linked together by peptide bonds; these bonds are formed by the action of proteolytic enzymes on older proteins.

##### Jean Pengelly

Jean Pengelly is a teacher who strives to be the best educator she can be, and loves helping her students grow. She has been teaching for 10 years now, and each day is different than the last. Jean's passion lies in working with children who are on the Autism spectrum. Her goal as an educator is to help these kids learn about themselves and their environment so they can become successful members of society.

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