Question

What is the chemical equation for cellular respiration?

Answer 1

Cellular respiration (being considered as a single reaction) can be described as a reaction between glucose and oxygen to produce carbon dioxide and water along with the release of energy which is useful for cellular activities. It can be expressed as: $glucose\text{ }+\text{ }oxygen\text{ }\xrightarrow{{}}\text{ }carbon\text{ }dioxide\text{ }+\text{ }water\text{ }+\text{ }energy$

Complete answer: As we know that cellular respiration is a set of metabolic reactions and processes which take place in the cells of organisms to convert chemical energy from ${{O}_{2}}$molecules and nutrients into “adenosine triphosphate” (ATP), and later on release waste products. The reactions involved in cellular respiration are catabolic reactions in which large molecules are broken into smaller ones to release energy which is used as a fuel for cellular activity. This overall reaction occurs in a series of biochemical steps among which few are redox reactions.
-The chemical equation for cellular respiration is given below:-
${{C}_{6}}{{H}_{12}}{{O}_{6}}+6{{O}_{2}}\to 6C{{O}_{2}}+6{{H}_{2}}O+energy$
The above reaction is formulated by the help of following 3 processes:-
-Glycolysis: It is the breakdown of glucose molecules into two three carbon molecules i.e. pyruvate (pyruvic acid).
-The Tricarboxylic Acid cycle or Krebs cycle: Here the three carbon pieces are pulled apart bit by bit to release the energy stored in those covalent bonds and this is where most of the $C{{O}_{2}}$ is formed.
-The Electron Transport Chain and Oxidative Phosphorylation: This sequence requires the ${{O}_{2}}$ molecules and produces most of the energy. This energy releases in the form of “adenosine triphosphate” (ATP).

Note: Although we may think of cellular respiration as a combustion reaction but it clearly does not resemble one when it occurs in a living cell because of the slow and controlled release of energy from the series of reactions.