What is cellular respiration? Cellular Respiration is the process that takes place in cells to convert food into energy. This process is also known as internal respiration. In order to release the maximal amount of energy, the molecules of Carbon, Hydrogen, Oxygen and Nitrogen which make up our food are stored as a high energy molecule known as ATP or Adenosine Triphosphate.

Cellular respiration equation

When energy is needed, ATP is broken down using an enzyme (known as ATPase) into ADP (Adenosine Diphosphate). This process breaks the high energy Phosphate (P) bond and so provides energy for use by the body. Here is the equation you may see in text books:

ATP = ADP + P +Energy

The human body is also capable of resynthesising ATP to allow it to continue producing energy. To do this it must use energy to reverse the equation shown above. This is known as an endothermic reaction as it requires energy. The breakdown of ATP is called exothermic as it produces energy. The process of breaking down and resynthesising ATP is efficient at producing energy as less energy is required to resynthesis the ATP than is made to break it down. Here is the Resynthesis equation:

Energy + ADP +P = ATP

 

What are the Energy Systems?

There are two energy systems used in during the process of respiration. Aerobic Respiration, meaning 'with oxygen' which is used for long-term, steady paced exercise and day-to-day activities and Anaerobic Respiration or 'without oxygen' which produces fast bursts of energy for short, powerful bursts. The Anaerobic system can be divided into two further systems, ATP-PC and Lactic acid. All energy systems work together, but the intensity and type of activity will determine which system is predominant.

 

Related Articles

Effects of Exercise

Exercise affects the circulatory system, respiratory system and the muscles. Short term effects occur immediately as we begin to exercise. Long term effects are more concerned with adaptive changes...

Human Digestive System

The primary function of the digestive system is to break down food both mechanically and by the use of enzymes, so that it can be used by the body for energy and cell growth and repair. It consists...

Oxygen Debt & Recovery

What is oxygen debt? When you have a short intense burst of exercise such as sprinting you generate energy for this anaerobically or without oxygen. When you stop exercising you are still breathing...

Aerobic System & Krebs Cycle

Aerobic metabolism means 'with oxygen' and occurs when energy is produced in the body from chemical reactions that use oxygen. The aerobic system produces the largest amounts of energy, although at...