What are the chemical products of respiration in human?

Cellular respiration is a set of metabolic reactions that take place in the cells of organisms to convert biochemical energy from nutrients into ATP, and then release waste products.

In humans, the chemical reactions involved in cellular respiration are as follows:

1. Glycolysis: This process takes place in the cytoplasm of the cell, where one molecule of glucose (a six-carbon sugar) is broken down into two molecules of pyruvate (a three-carbon molecule). This process also results in the production of 2 molecules of ATP (adenosine triphosphate, the energy currency of the cell) and 2 molecules of NADH (nicotinamide adenine dinucleotide, an electron carrier).

2. Link Reaction (Pyruvate Decarboxylation): This reaction occurs in the mitochondrial matrix, where each pyruvate molecule from glycolysis is converted into a molecule of acetyl-CoA. In this process, one molecule of carbon dioxide (CO2) is released, and 1 molecule of NADH is produced.

3. Citric Acid Cycle (Krebs Cycle): This series of reactions also occurs in the mitochondrial matrix. Here, the acetyl-CoA molecules from the previous step are further oxidized to produce carbon dioxide, ATP, and more NADH and FADH2 (flavin adenine dinucleotide, another electron carrier).

4. Oxidative Phosphorylation (Electron Transport Chain): This process takes place in the inner mitochondrial membrane. The NADH and FADH2 molecules generated in glycolysis and the citric acid cycle pass their electrons to the electron transport chain. This series of redox reactions ultimately leads to the formation of water and oxygen, and the generation of a significant amount of ATP through chemiosmosis.

Therefore, the chemical products of respiration in humans include carbon dioxide (CO2), water (H2O), and energy in the form of ATP molecules.