• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

The genetic code

Extracts from this document...

Introduction

The genetic code I will discuss the genetic code, looking at the specific areas of transcription/translation, the codon/anticodon, mutation, sense/antisense, the non-overlapping codon and the intron. The genetic code is the base sequence of the DNA that has been copied to a base sequence in mRNA. "This sequence is the genetic code for a protein."1 This code is for a single amino acid, which is called a codon. The genetic code has two very important features. The first is a non-overlapping codon; this codon is a specific start codon, which ensures that the ribosome correctly 'read' the mRNA in a "unique way"1. This unique way is in sets of three, "64 triplets of nucleotides."3 For example: AUG AAU TCG CCU. The second feature is that the code is degenerate. This means some of the amino acids are coded for more than one codon. Transcription is the transfer of information from DNA to mRNA. ...read more.

Middle

This is the process of translation. Appropriate or different, specific tRNA carries corresponding amino acids."1 "The other "end" of the tRNA molecule has an "acceptor" site where the tRNA's specific amino acid will bind."4 Energy is needed to attach amino acids to the tRNA (ATP). So protein synthesis doesn't rely on the diffusion of amino acids, but does rely on transfer RNA (tRNA). Each tRNA molecule has three unpaired bases; these as a collective are called an 'anticodon'. The tRNA pairs with the mRNA the same way as before, matching with the codon in the ribosome. The tRNA bases pair with the mRNA bases A=U, C=G, G=C and U=A. The ribosome then removes the amino acids for the tRNA molecule and bonds it to the others. As the ribosome move along the mRNA three bases at a time, the ribosome will continue linking the amino acids brought there by the tRNA to form a protein molecule. ...read more.

Conclusion

Generally these differences do not make any impact on our health and are called polymorphism (poly means many; morphisms means forms). They are quite common. So while the genetic code may be slightly changed by having a polymorphism, the change has not significantly altered the gene message: the information is still understood by the cell. However, some changes to the genetic code in genes cause the message to be changed so that it is no longer understood by the cell: the gene is broken or faulty. Changes that make the genes faulty are called mutations. If the message to the cell comes from a faulty gene, the cell will not make the correct copy of the product, will make it in reduced amounts or will not make it at all. Faults in the genes may cause a problem with the development and functioning of different body systems or organs and result in a genetic disorder. Mutations that may be beneficial are that of immunity to a disease or a useful family trait. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Genetics, Evolution & Biodiversity section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Genetics, Evolution & Biodiversity essays

  1. Marked by a teacher

    An Investigation into the Mitotic Nuclear Division of Allium Sativum Root Tip Cells, and ...

    5 star(s)

    and M phase. M phase is itself composed of two tightly coupled processes: mitosis, in which the cell's chromosomes are divided between the two daughter cells, and cytokinesis, in which the cell's cytoplasm physically divides. Cells that have temporarily or reversibly stopped dividing are said to have entered a state

  2. Marked by a teacher

    MENTAL HEALTH

    4 star(s)

    Delayed - Demented - Alzheimer's - Slow - Crazy - Cuckoo - Psycho - Wacko - Nut job - The above words were from a primary research of just walking around and asking people their opinion of people who are mentally ill.

  1. The Biology of Autistic Spectrum Disorder and the Social Implications

    This reflects on the 1 in 3 children that have changed schools in the last five years in addition to moving from primary to secondary school. Those moves could be due to the 1 in 5 being excluded: 67% of those 1 in 5 autistic children being excluded more than

  2. Recombinant DNA, genetically engineered DNA prepared in vitro by cutting up DNA molecules and ...

    Other traits, such as human eye color, are specific to individuals, and their inheritance is directly dependent on the genetics of the parents. The physical key to heredity lies within the nucleus of the cell in structures known as chromosomes.

  1. Structural Properties of mRNA and tRNA

    is added to the codon end of the molecule. This allows the mRNA to carry out its function. There are regions of DNA that are not used for translation, these regions are called introns. The regions of DNA that are translated into protein are known as exons.

  2. Investigating what effect varying the concentration of copper sulphate has on the enzyme Catalase ...

    Concentration = 0.6M Amount of 02 produced (cm�) Time (seconds) 1st 2nd 3rd average Time (seconds) 1st 2nd 3rd average 30 2 1.4 0.7 1.4 30 1 1.2 0.6 0.9 60 2.7 2.2 0.9 1.9 60 1.6 1.7 1.2 1.5 90 3.1 2.6 1.2 2.3 90 2.2 2.3 2 2.2

  1. Genetics: The code broken?

    is called gene expression * A gene is considered 'active' or 'expressed' when its specific m-RNA and polypeptide is produced, and 'inactive' or 'silent' when the gene produces neither product * Sometimes newly formed gene products cannot be directly identified, however the gene action can be inferred indirectly by noting

  2. Genetics- Transcription and Translation

    The first step of translation is Initiation, which takes place in the P-site of the ribosome. The small and large ribosome sub-unit bind to the mRNA; the small sub-unit sits at the bottom and the large sub-unit which holds the A, P and E sites sit at the top of the mRNA strand.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work