Dna Rn Double Helix Structure - 1335 Words

DNA RNA Double helix structure made of two DNA strands Made up of a single strand In DNA adenine base pairs with thymine In RNA adenine base pairs with uracil There is only one type of DNA There are three types of RNA; messenger RNA (mRNA), ribosomal RNA (rRNA) and transfer RNA (tRNA) Made up of monomers called nucleotides, which is made up of three parts; pentose sugar, nitrogenous base and a phosphate group Made up of monomers called nucleotides, which is made up of three parts; pentose sugar, nitrogenous base and a phosphate group Contains purine and pyrimidine nitrogenous bases Contains purine and pyrimidine nitrogenous bases DNA is a nucleic acid (a molecule which is made up of a long chain of nucleotides) RNA is a nucleic†¦show more content†¦DNA contains short sections of genes at regular intervals which store genetic information, this is known as the genetic code. The genetic code is the sequence of bases in the gene which will code for a particular protein. The genetic code is read in terms of triplets, every three bases is a triplet which codes for one amino acid. The genetic code is translated by reading each triplet in turn whilst assembling the chain of amino acids based on the triplets [ 4 ]. So it other words the genetic code determines the sequence of amino acids, and depending on the sequence of amino acids a protein is produced. Any small change such as a change in one of the bases can result in a protein not working as it should and can therefore be harmful. The body can create 20 amino acids itself, all of which are coded for by the base sequence in the DNA. Three bases code for o ne amino acid therefore you have 64 triplets (codon’s) that code for 20 amino acids, 3 of those triplets are stop codon’s (UGA,UAA, UAG) which signal the end of the genetic code, they do not code for an amino acid. And there is one start codon which signals the beginning of the genetic code. However if the start codon (AUG) is found elsewhere