You are here:



Deb wrote at 2014-05-23 12:28:12
Energy is produced in the body through a process called respiration, where food substances are broken down in presence of oxygen.Energy is produced in the body through a process called respiration, where food substances are broken down in presence of oxygen.This process is referred to as aerobic respiration.

It is also possible for food substance to be broken down in absent of oxygen. this is referred to as anaerobic respiration.

The energy is combined with Adenosine diphosphate(ADP) with a phosphate molecule to form adenosine triphosphate

ATP is a high energy molecule that stores energy and avails it to the cell. ur body also requires energy for

performing various functions. This energy

mainly comes from carbohydrates and fats

that we take as food. Carbohydrates are

decomposed into glucose or its derivatives in

the stomach. Glucose is soluble in blood. It is

transported by the blood cells to various

parts of the body where it reacts with oxygen

in a series of steps producing carbon dioxide

(CO2), water (H2O) and energy.

C6H12O6 +6O2 ------------6CO2 +6H2O



This process is very much similar to the

process of burning. However, this process

takes place inside our body quite slowly and

at the much lower temperature. This slow

combustion of food material takes place at

the body temperature because of the

catalytic action of enzymes. This slow combustion of food in the cells resulting in

the release of energy is called respiration.

Carbon dioxide and water, which are formed

during respiration, are expelled through

various organs of the body. The energy

released in respiration fulfils the energy

needs of the body.

Although respiration is similar to combustion

in respect of the products formed and the

energy released yet it differs from it in many


The process of manufacturing energy in the human body is termed metabolism.

Metabolism is not the result of a single process but is the culmination of a series of processes ;Eating of foods containing different nutrients.

Digestion of foods into smaller macro-nutrients such as glucose, fats and amino acids.

Absorption of the macro-nutrients from the stomach into blood stream.

Transport of the nutrients to the cells

Further chemical breakdown (oxidation) of fat and glucose to produce energy in two forms; heat and ATP.  


All Answers

Answers by Expert:

Ask Experts


Walter Hintz


Science teacher for over 50 years. MSc. in biology. I can answer questions in general biology, zoology, botany, anatomy and physiology and biochemistry.


I have a MSc in biology and have been a science teacher for over 50 years. At present I am a faculty member at a college and a science consultant at seven catholic schools.

The Ohio journal of Science
Momentum-The Journal of the Catholic Education Association

©2017 All rights reserved.