Protein Synthesis
The instructions for making a protein are coded into the DNA by the order of its nitrogenous bases. First, helicase "unzips" the DNA and then enzymes start building an mRNA (messenger RNA) molecule according to the DNA's order of bases:
After the mRNA is made, it leaves the nucleus and out to the cytoplasm, where it finds a ribosome. On an mRNA, a set of three nitrogenous bases that code for a specific amino acid is called a codon. The codons determine the primary structure of the protein.
There is also a type of RNA called a tRNA (transfer RNA). This RNA has an anticodon (three nitrogenous bases that are complementary to the codon on mRNA) that codes for the same amino acid. Its job is to find the amino acid that the genetic code asks for, and bring it to the ribosomes.
The ribosome's job is to build peptide bonds connecting the amino acids to form a polypeptide. It uses the information on mRNA and the amino acids that tRNA brings to build a polypeptide.
Later on, the polypeptide is altered and "edited" until it becomes a real protein molecule.
That a simple explanation of how proteins are made, and hopefully it wasn't too confusing.
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Nucleic Acids
- Nucleotides
- DNA and RNA
- Protein synthesis
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