...the key of A minor. 5 n-count The key on a map or diagram or in a technical book is a list of the symbols or abbreviations used and their meanings. You will find a key at the front of the book. 6 adj The key person or thing in a group is the most important one.
ATP (Adenosine triphosphate). 1  It is the major energy currency of the cell, providing the energy for most of the energy-consuming activities of the cell. 2  It is one of the monomers used in the synthesis of RNA and, after conversion to deoxyATP (dATP), DNA.3  It regulates many biochemical pathways. It is the major energy currency of the cell, providing the energy for most of the energy-consuming activities of the cell. 2  It is one of the monomers used in the synthesis of RNA and, after conversion to deoxyATP (dATP), DNA. 3  It regulates many biochemical pathways.
Mitochondria. Mitochondria are rod-shaped organelles that can be considered the power generators of the cell, converting oxygen and nutrients into adenosine triphosphate (ATP). ATP is the chemical energy currency of the cell that powers the cell's metabolic activities. This process is called aerobic respiration and is the reason animals breathe oxygen.