Health and Social Care Unit 5 Energy Metabolism

Energy Metabolism

Energy Metabolism, as defined by www.nature.com, ‘is the process of generating Adenosine Triphosphate (ATP), a form of energy’, from nutrients, such as Glucose (sugar). There are two parts to Energy Metabolism: Anabolism and Catabolism. Anabolism is forming large, complex molecules from small, less complex ones. Anabolism is the breakdown of large, complex molecules into small, less complex molecules.

Glucose + Oxygen = Carbon Dioxide + Water + Energy

C6H12O6 + 6O2 -> 6CO2 + 6H2O + ATP Energy

The equation above shows everything needed to create energy. Glucose is part of the nutrients we need to acquire our energy, and to release the energy our cells need Oxygen. Once we use up the glucose and oxygen, our cells create the waste products: Carbon Dioxide and Water. Carbon Dioxide is released as it is not needed by the body.

There are 3 main body systems that relate to Energy Metabolism:

1. The Digestive System – where we get the nutrients.
2. The Respiratory System – where we get the Oxygen.
3. The Cardiovascular System – where everything is transported.

In order for the body to perform any function, energy and oxygen are needed, and so each system is necessary. For instance:

The Digestive System is made up of the mouth and saliva glands, the oesophagus, the stomach, the liver, the gall bladder, the stomach, the small and large intestines, and the pancreas. Food enters the mouth and is immediately being broken down by the enzymes in saliva, which is secreted by the saliva glands. The food is then passed down the throat and oesophagus into the stomach, where stomach acid breaks down the food, and supplies enzymes with an environment that maximises efficiency (speeds up the rate of chemical changes, but does not denature the enzymes).

The broken down food is finally passed into the small intestines, where nutrients are absorbed into the blood stream, and any food that is not broken down enough is mixed with bile, produced in the liver and stored in the gall bladder, to be broken down even more. Once passed from the small intestines to the large intestines, any remaining nutrients and water is absorbed into the blood stream. The pancreas produces a hormone known as insulin, which converts glucose into glycogen, where it is then stored in either the liver, or in muscle cells, to be converted back into glucose, when energy is needed, by a different hormone, known as glucagon, which is also produced by the pancreas.

The Respiratory System is made up of the lungs, the ribcage, the diaphragm, the bronchi, the bronchioles, and the alveoli. When we breathe in, oxygen (and the other components of air) fills our lungs, causing them to inflate, our chest to expand, and our diaphragm to contract and push outwards. The oxygen travels down our throat and windpipe, to the bronchi and bronchioles within our lungs, and finally to the alveoli, which is connected to the blood system by a partially permeable membrane, which allows small gaseous molecules to pass through, but prevents larger molecules such as blood cells from passing through. The Oxygen passes into the blood system and is attached to red blood cells, which in turn releases any Carbon Dioxide into the lungs. This is then passed through the alveoli to the bronchioles and bronchi then back through the windpipe and throat, when we breathe out.