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'''Proteins''' are complex organic compounds whose basic structure is a primary chain of amino acids covalently bonded via [[peptide bond]]s and folded into a certain shape. This tertiary fold dictates the function of the protein within the organism. They can take on many forms and perform distinct functions including (but certainly not limited to) structural, enzymatic, information storage, intracellular signaling, and transportation roles. In terms of structure, proteins are important in the construction and integrity of different body tissues including connective and muscular, as well as endocrine/exocrine glands. <ref> http://www.hsph.harvard.edu/nutritionsource/protein.html </ref>  

'''Proteins''' are complex organic compounds whose basic structure is a primary chain of amino acids covalently bonded via [[peptide bond]]s and folded into a certain shape. This tertiary fold dictates the function of the protein within the organism. They can take on many forms and perform distinct functions including (but certainly not limited to) structural, enzymatic, information storage, intracellular signaling, and transportation roles. In terms of structure, proteins are important in the construction and integrity of different body tissues including connective and muscular, as well as endocrine/exocrine glands. <ref> http://www.hsph.harvard.edu/nutritionsource/protein.html </ref>  

===Synthesis===

==Synthesis==

Proteins are synthesized by cytoplasmic structures composed of catalytic rRNA and proteins called [[ribosomes]]. Ribosomes translate information coded in mRNA (transcribed from genomic DNA, specific regions known as [[genes]]) after editing and manipulation by nuclear [[spliceosome]]s. The nascent protein is elongated in the ribosome through addition of different amino acids specified by codons (sets of three nucleotides) in the mRNA molecule. The formation of the protein chain requires the codon, a molecule of transfer RNA (tRNA) charged with a particular amino acid, and the tRNA's anti-codon. A molecule of water is expelled after each peptide bond is formed, hence the name "condensation reaction".

Proteins are synthesized by cytoplasmic structures composed of catalytic rRNA and proteins called [[ribosomes]]. Ribosomes translate information coded in mRNA (transcribed from genomic DNA, specific regions known as [[genes]]) after editing and manipulation by nuclear [[spliceosome]]s. The nascent protein is elongated in the ribosome through addition of different amino acids specified by codons (sets of three nucleotides) in the mRNA molecule. The formation of the protein chain requires the codon, a molecule of transfer RNA (tRNA) charged with a particular amino acid, and the tRNA's anti-codon. A molecule of water is expelled after each peptide bond is formed, hence the name "condensation reaction".

After the protein has been generated, it is assisted by other proteins termed chaperones that aid in the formation of the proper conformation. A protein is always synthesized in one direction so, invariably, proteins also exhibit the physical property known as polarity. All [[polypetide]]s possess free N-terminal(Amine; NH2) and C-terminal (Carboxylic Acid; COOH) ends. The protein may then be further edited post-translationally by certain enzymes. Examples of such modifications include, [[isoprenylation]], [[palmitoylation]], [[myristoylation]], [[methylation]], [[acetylation]], N-terminal [[proteolysis]], and [[disulfide bond]] linkage. These modifications often have some bearing on the function and localization of the protein. After these processes occur, the protein can be transported to other sub-cellular organelles/locations such as the plasma membrane, golgi apparatus, endoplasmic reticulum, and vesicles where they perform their pre-programmed function. Vesicular proteins are usually shuttled to the plasma membrane, or reserved cytoplasmically for secretion at a later time.

After the protein has been generated, it is assisted by other proteins termed chaperones that aid in the formation of the proper conformation. A protein is always synthesized in one direction so, invariably, proteins also exhibit the physical property known as polarity. All [[polypetide]]s possess free N-terminal(Amine; NH2) and C-terminal (Carboxylic Acid; COOH) ends. The protein may then be further edited post-translationally by certain enzymes. Examples of such modifications include, [[isoprenylation]], [[palmitoylation]], [[myristoylation]], [[methylation]], [[acetylation]], N-terminal [[proteolysis]], and [[disulfide bond]] linkage. These modifications often have some bearing on the function and localization of the protein. After these processes occur, the protein can be transported to other sub-cellular organelles/locations such as the plasma membrane, golgi apparatus, endoplasmic reticulum, and vesicles where they perform their pre-programmed function. Vesicular proteins are usually shuttled to the plasma membrane, or reserved cytoplasmically for secretion at a later time.

===Nutrition===

==Nutrition==

Adult humans need a minimum of 1 gram of protein for every kilogram of body weight per day to keep from slowly breaking down their own tissues. Failure to receive enough protein can cause stunted growth, loss of muscle mass, decreased immunity, weakening of the heart and respiratory system, and eventually death. <ref> http://www.usda.gov/ </ref>

Adult humans need a minimum of 1 gram of protein for every kilogram of body weight per day to keep from slowly breaking down their own tissues. Failure to receive enough protein can cause stunted growth, loss of muscle mass, decreased immunity, weakening of the heart and respiratory system, and eventually death. <ref> http://www.usda.gov/ </ref>