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One of the central themes in biology is how DNA RNA, and proteins are related. Describe how genetic information flows between Those types of molecules. Include the results of the processes of transcription and translation.

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Answer/Explanation:

DNA is transcribed into RNA, RNA is translated into protein

The information contained in DNA can be copied (transcribed) onto a molecule of RNA, as these languages are essentially the same (although RNA uses uracil in place of thymidine). This process is carried out by an enzyme called RNA polymerase through the process of complementary base pairing, and occurs in the nucleus. The two strands of DNA are separated, and the RNA polymerase enzyme uses a template strand of DNA to synthesise a new molecule of RNA.

Once the RNA is produced (often called the messenger RNA (mRNA), as it contains the message from the DNA). The RNA is processed, before being exported into the cytoplasm. Here, translation can begin.

Translation is the process where mRNA is converted into a polypeptide sequence, which becomes a mature protein. This process occurs on the ribosome. The mRNA is attached to the ribosome, and special molecules called tRNAs are used to build a polypeptide chain from amino acids.

tRNAs recognise triplet (3 nucleotide) sequences on the mRNA called codons. They possess what is called an "anticodon", which is complementary to a codon on the mRNA, and also corresponds to a particular amino acid.

The ribosome moves along the length of the mRNA, permitting the attachment of tRNAs (and their corresponding amino acids) to their complementary sequence present on the mRNA. As these fall into place, the tRNA drops off its amino acid, and leaves. The same happens again, and a polypeptide bond occurs between the two amino acids. This keeps happening, until a full polypeptide chain is made.

This polypeptide chain is processed into a mature protein.

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