what is the major source of energy for cellular reaction?
a nucleotide derived from adenosine that occurs in muscle tissues
The major source of energy for cellular reactions is a molecule called adenosine triphosphate (ATP). ATP is often referred to as the "energy currency" of the cell because it acts as a universal energy carrier for various cellular processes.
To understand why ATP is the major source of energy, you need to understand how it is produced and utilized within the cell. ATP is generated through a process called cellular respiration, which occurs primarily in the mitochondria. During cellular respiration, organic molecules (such as glucose) are broken down, and the energy released from these molecules is used to generate ATP.
The breakdown of glucose occurs in a series of steps, including glycolysis, the Krebs cycle (also known as the citric acid cycle), and oxidative phosphorylation. These processes involve several enzyme-catalyzed reactions that extract energy from glucose and convert it into ATP.
Once ATP is formed, it can be utilized to power various cellular activities. When a particular cellular reaction requires energy, ATP is hydrolyzed by an enzyme called ATPase. This hydrolysis reaction breaks down ATP into adenosine diphosphate (ADP) and inorganic phosphate (Pi), releasing energy in the process.
The energy released from ATP hydrolysis is then utilized by the cell to perform various functions like muscle contraction, active transport processes, DNA synthesis, and many other essential cellular activities.
In summary, the major source of energy for cellular reactions is ATP. It is produced through the breakdown of organic molecules, primarily glucose, during cellular respiration. The energy stored in ATP is then released through hydrolysis and utilized by the cell to drive various biological processes.