3.5.2 Outline DNA Transcription
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3.5.2 Outline DNA Transcription in
3.5.2 Outline DNA Transcription in terms of the formation of an RNA strand complimentary to the DNA strand by RNA Polymerase
Before outlining the process of DNA Transcription I feel it first important to give an overview of protein synthesis to put the process in context. DNA is composed of genes and mRNA is formed from one of these genes in the process of transcription. The code on this mRNA (transcribed from DNA and therefore complimentary to the gene in DNA) would then be used in Translation to code for a polypeptide chain. This chain would ultimately be folded to form a protein.
In this video I deal specifically with Transcription, Translation is dealt with in 3.5.4.
Transcription begins when a gene is located on the DNA and that particular part of the DNA is unwound/unzipped by an enzyme. Once that particular area has been unzipped you then find DNA existing as two single strands (in that area) and one of those strands is going to form a template on which mRNA will be formed. The piece of mRNA is formed by the enzyme RNA Polymerase by adding complimentary RNA nucleotides to the template strand of the DNA. Notice only one strand of the DNA is used to do this, the other strand remains unused. The piece of mRNA formed is single stranded. As DNA is made of multiple genes, the piece of mRNA formed is ultimately shorter than the complete length of DNA because it is formed from only a single gene. The DNA is identified as it contains thymine (T) whereas the RNA can be identified as containing uracil (U) instead. Once formed the mRNA moves from the nucleus (site of transcription) to the cytoplasm where translation will take place to form a polypeptide chain (See 3.5.4)
Before outlining the process of DNA Transcription I feel it first important to give an overview of protein synthesis to put the process in context. DNA is composed of genes and mRNA is formed from one of these genes in the process of transcription. The code on this mRNA (transcribed from DNA and therefore complimentary to the gene in DNA) would then be used in Translation to code for a polypeptide chain. This chain would ultimately be folded to form a protein.
In this video I deal specifically with Transcription, Translation is dealt with in 3.5.4.
Transcription begins when a gene is located on the DNA and that particular part of the DNA is unwound/unzipped by an enzyme. Once that particular area has been unzipped you then find DNA existing as two single strands (in that area) and one of those strands is going to form a template on which mRNA will be formed. The piece of mRNA is formed by the enzyme RNA Polymerase by adding complimentary RNA nucleotides to the template strand of the DNA. Notice only one strand of the DNA is used to do this, the other strand remains unused. The piece of mRNA formed is single stranded. As DNA is made of multiple genes, the piece of mRNA formed is ultimately shorter than the complete length of DNA because it is formed from only a single gene. The DNA is identified as it contains thymine (T) whereas the RNA can be identified as containing uracil (U) instead. Once formed the mRNA moves from the nucleus (site of transcription) to the cytoplasm where translation will take place to form a polypeptide chain (See 3.5.4)
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