Explain The Three Main Components Of A Nucleotide

1a) There are five nucleotide bases which are Adenine, Guanine, Thymine, Cytosine and Uracil.

1b) There are three main components of a nucleotide which are a pentose sugar which can be either deoxyribose or ribose, a phosphate molecule and one of the 4 nitrogenous bases e.g. Adenine, Cytosine etc.

1c) There are 2 bases which make two different bases in the RNA and DNA, which are Pyrimidines and Purines. Adenine and Guanine are purine bases because they are large bases and they each also have 2 rings of carbon and nitrogen atoms and purines also tend to be double ring bases. Thymine and Cytosine are pyrimidines bases because they have a 1 carbon nitrogen ring base, and pyrimidines are also single ring bases.

Pyrimidines and Purines bind in

Three DNA letters are used for a single amino acid because the DNA has 4 letters (A, T, G &C), which have to specify the twenty different amino acids that create up proteins. One DNA letter for one amino acid can only code 4 maximum amino acids, if 2 letters could code up to 16 amino acids, however 3 DNA letters are more than enough combination which can code for all 20 amino acids, and this is why it is a triplet code. The order and number dictated by the number of the the base triplet create an amino acid.

The degenerate code is a code in which different code words can have the same meaning. The triplet code is a degenerate code because in many occurrences different codons can mean the same amino acid. In the triplet code a lot of amino acids can be encoded by more than 1 codon.

2c) Both introns and exons are a part of genes, however the difference between them is that only exons code for genes and introns don’t. Exons are coding region in the genes which get broken up by introns which are the non-coding regions in the gene. Introns and exons are included during the transcription process when the gene is being copied into a pre messenger RNA. Introns get removed during the RNA merging process however exons join to form a continuous coding sequence.

Task

When RNA polymerase enzyme reaches a triplet base which’s codon reads ‘stop’, transcription ends. The mRNA gets processed further on as it contains introns are not needed for protein synthesis. The pre-messenger RNA gets split up so it can remove introns which then create mRNA in RNA splicing process. The coding sequences get merged together and ‘cap’ which is a special nucleotide gets added to one end, and a long tail gets added to the other end which contains about hundred to two hundred adenine nucleotides. This mRNA copies which have been formed act as a blueprint for protein synthesis, in the translation process. The mRNA would leave the nucleus and into the cytoplasm, through the big holes in the nuclear