Biology: Cell

Apoptosis is the process of programmed cell death (PCD) that may occur in multicellular organisms. Apoptosis plays a crucial role in developing and maintaining the health of the body by eliminating old, unnecessary and unhealthy cells.

Kreb's cycle is a cycle of enzyme-catalyzed reactions in living cells that is the final series of reactions of aerobic metabolism of carbohydrates, proteins, and fatty acids. Due to this carbon dioxide is produced, oxygen is reduced and ATP is formed. Kreb's cycle generates the maximum number of ATP atoms in our system.

C₆H₁₂O₆+6O₂⇒6CO₂+6H₂O+energy (as ATP)

In a eukaryotic cell, the citric acid cycle occurs in the matrix of the mitochondrion. This cycle was discovered by Hans Kreb's in 1937.