Transcription and Translation Flashcards
Identify where transcription occurs
nucleus
Identify where translation occurs
cytosol
explain the role of the promoter region on DNA in order to initiate transcription
the promoter is found at the beginning of a gene and is where RNA polymerase binds to start transcription
outline the role of RNA polymerase in order to create a RNA molecule
RNA polymerase is an enzyme that uses the DNA template to create a mRNA transcript, complementary to the DNA template and identical to the DNA coding strand -> except uracil replaces thymine
compare and contrast pre-mRNA and mature mRNA and explain the RNA processing that takes place to result in these different molecules
pre-mRNA contains introns and a 3’ and 5’ UTR
RNA processing is the method to turn pre-mRNA into mature mRNA. It involves the addition of a methyl cap at the 5’ end, and a poly-A tail at the 3’ end.
Splicing will also occur causing the removal of introns and the joining of exons.
mature mRNA is the fully processed form of RNA that is now ready to be translated
explain the role of the ribosome in translation
the ribosome is the site of translation, this is where the mRNA docks and polypeptides are created
explain the relationship between a codon and an anti-codon and where they are found
codons are groups of three base pairs found within mRNA - these code for specific amino acids
anti-codons are found on tRNA
⁃ They are complementary to each other
link the role of tRNA to the formation of a polypeptide during translation
the role of tRNA is that it carries amino acids to the ribosome and delivers it to the developing polypeptide chain - they have complementary anti-codons to the mRNA codons
outline the role of a STOP codon
they signal to the ribosome to end translation
STOP codons have no amino acids
define the terms exon and intron and link this to alternative splicing during post-transcriptional modifications
introns are non-coding segments of DNA and need to be removed to create a functional protein
exons are coding regions that are spliced together
define the term promoter and outline its role in transcription and binding of RNA polymerase
the promoter is the site where RNA polymerase binds in order to initiate transcription
explain the importance of controlling gene expression in terms of saving energy and resources
gene expression requires a large amount of energy and resources. Therefore, It would require a significant amount of energy for an organism to express every gene at all times, so it is more energy efficient to turn on the genes only when they are required.
