tRNA, mRNA, RNA, Protein Synthesis and DNA

tRNA

tRNA is the molecule which transfers the active amino acids the the ribosome site of the newly forming polypeptide chain.
In protein synthesis this happens during the translation phase.
tRNA has three anticodon sites which can only attatch to specific amino acids, which then attach to the codon on the mRNA.
It is known to have a cloverleaf type structure.
The link between tRNA and amino acids is synthesized by aminoacyl tRNA synthetase.

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mRNA is the messenger RNA it is transcribed from DNA and carrys a code for specifc protein products e.g. amino acids, to allow them to attach.
It takes its information the the ribosome site hre i can then translate the amino acids into a polypeptide chain.
mRNA carries genetic information which is encoded into nucleotides. It then arranges it into codons and into base pairs of three.
Each codon codes for a specific amino acid which comes from the tRNA, apart from the stop codon which ends protein synthesis.
mRNA has to also get rid of introns which interrupt exons from producing proteins.
The usual start code of mRNA is AUG and the stop code will usually begin with the letter U.

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Ribonucleic acid is what RNA stands for.
It consists of long chains of nucleotides. The nucleotides each consist of a ribose sugar, nitrogenus base and a phosphate group.
RNA is single stranded.
In the base pairs RNA has Uracil instead of Thymine.
RNA is transcribed from DNA by ribosome polymerases and other enzymes.
The main function of RNA is protein synthesis.

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Deoxyribonucleic acid is what DNA stands for.
DNA contains specific genetic information for each living organism and is used for long term information storage.
Genes in DNA are responsible for constucting other cell components such as RNA molecules for protein synthesis.
DNA is double stranded and the strands are polymers made of deoxyribose sugar and phosohate groups,which are hel together by ester bonds. These double strands run opposite to eachother which makes them anti-parallel.
Along the strands attached to each sugar is one of four bases.
DNA consists of structures known as chromosomes, which are repicated during DNA relication.
Chromosomes contain chromatin proteins.
The base pairs in DNA are Adenine, Thymine, Guanine and Cytosine which are joined by hydrogen bonds.
People who have down sydrome have a defect of the chromosome 21.

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