Cellular respiration is the process by which cells convert sugar into carbon dioxide and water. During this biochemical reaction, energy in the form of adenosine triphosphate (ATP) is released. ATP molecules are the type of energy cells require to perform the functions necessary to life.
Cellular respiration and "regular" respiration, or breathing, are linked, but they are not the same. When we breathe, we take in the oxygen that powers the cellular respiration reaction, and we exhale the carbon dioxide that is produced during the reaction.
Cellular respiration is divided into three main steps: Glycolysis, the citric acid cycle and oxidative phosphorylation.
This first step of the respiration reaction takes place in the cytoplasm, or fluid, of the cell. During this step, glucose, a sugar, is broken down into pyruvic acid.
Citric Acid Cycle
The final two steps of the respiration reaction take place inside the cell's mitochondria, which are "power factories" of sorts for cells. During the citric acid cycle, pyruvic acid is converted into carbon dioxide, water and two enzymes needed in the final stage of the reaction. The citric acid cycle is also called the krebs cycle.
During this "payoff" phase of the respiration reaction, oxygen is required to power a complex electron transport chain involving the enzymes produced during the citric acid cycle. The result is the release of 38 molecules of ATP.
- Biology: Concepts and Connections; Neil A. Campbell; 2009
Types of Respiration
When discussing respiration, you have to be specific about what type you are referring to. Respiration in scientific research is often called...
Difference Between Cellular Respiration & Breathing
The processes of cellular respiration and breathing are part of the same process. When you inhale, carbon dioxide is replaced by oxygen...
Cellular Respiration in Plants
Cells in both plants and animals use cellular respiration as a means of converting stored energy into a chemical that individual cells...
What Is External Respiration?
External respiration is part of a three-part process that includes external respiration, internal respiration and cellular respiration, which together constitute how we...
Where Does Respiration Occur?
The most common examples of respiration occur in two places: in human lungs as part of breathing and in cells through a...
Factors Affecting Cellular Respiration
Cellular respiration is the method of transforming nutrients to energy. Some of the nutrients that go through the process of cellular respiration...
What Is Cellular Respiration?
Cellular respiration is the chemical reaction that helps a person to turn the sugar in food into energy. Find out how cellular...