We breath oxygen because it is needed to burn fuel [ sugars and fatty acids] in our cells to produce energy. Oxygen is also brought into the lungs via breathing; where it is transported by red blood cells to the entire body to be used to produce energy. The food we eat gives us protein, sugars, vitamins etc. for energy
The chemical process by which complex molecules of protein are made from simple molecules is called Respiration
<span>After
digestion, an amino acid not absorbed by the body and not used to build
proteins will first be subjected to removal from its amino group. If they are
not used for protein synthesis, amino acids becomes part of the metabolism
process. The body has the capability to create a subset of amino acids, also
known as non-essential amino acids because we don’t have requirement for them
in our diet. </span>
Animal skulls are said to protect the one of the most important organ in the body. Moreover, the bone has also some features that are important such as being able to identify the organ of the animal, knowing somehow the lifespan, diet and other similar biological traits.
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