MCAT Biology > Protein Synthesis
Proteins are some of the most important molecules in all of the function of the human body. Proteins are derived ultimately from DNA and form the basis for enzymes, hormones and many other important chemical compounds used through the body. In order to successfully create a workable protein from the genetic code requires a long and complicated biological process.
This process results in the creation of proteins from the genetic code based on the DNA which is in the nucleus off the cell. Through the processes of transcription and translation, the DNA is made into RNA which is then translated into a protein based on its unique base sequences.
See Genetic Code
The genetic code is the central building blocks of all life and is composed of the essential amino acids. These amino acids come together to form proteins which are necessary for building hormones, enzymes and other chemical compounds within the body.
Transcription begins with the unwinding of the DNA molecule to give access to the genes. Only one strand of DNA is used in order to create RNA. The template strand is called the anti-sense strand. Transcription creates the unique messenger RNA (mRNA) which is composed of RNA nucleotides and a 5' cap and a poly-A tail as a template. The 5' cap is bonded specially to the mRNA as to prevent degradation from outside forces. Likewise the poly-A tail protects the other 3' end of the mRNA from exonuclease degradation.
The general formula for mRNA in eukaryotic cells is:
5' Cap + Nucleotides + 3' poly-A Tail
Cancer is the result of the failure of the normal processes of protein synthesis and cellular replication through mitosis. Cancer cells continue to grow and replicate when normal cells would normally have stopped growth through chemical signals and control mechanisms.