RNAVSDNA Flashcards
What is RNA?
ribonucleic acid, a nucleic acid present in all living cells.
Its principal role is to act as a messenger carrying instructions from DNA for controlling the synthesis of proteins,
although in some viruses RNA rather than DNA carries the genetic information.
RNA is less chemically stable and more flexible
Single stranded
What is DNA?
Is the molecule which gives an organism its identity as well as continuity of life .
In addition, they provide instructions for how or when proteins should be made /build and maintain functioning cells , tissues and organism
What is tRNA?
Consists of single RNA strand
Tranfered from DNA.
Anti codons are written 3- 5
Codons written 5-3
What happens in Eukaryotes which doesn’t happen in Prokaryotes ?
In Eukaryotes, there are three RNA polymerase 1, 2, 3,
including proofing mechanism PRE mRNA is spliced and modified to produce mRNA which moves from the nucleus to the cytoplasm.
What happens during RNA processing ?
RNA splicing occurs where large portion of RNA molecules are removed .Leaving the others to reconnect
Pre -mRNA is spliced because the removal of introns is accomplished by large complex of proteins and small RNAs called spliceosome .
The introns are realised.
RNA splicing can occur without protein or additional mRNA .
RNA Splicing is one reason why human get along with the same gene as round worms.
The benefit of RNA splicing is that one gene can produce many different proteins as a result of what segments are treated as introns and exons.
Why do some RNA function as enzymes ?
RNA is single stranded
Contain functional groups that participate
the ability for RNA to hydrogen to bond with other nuclei acids .
Translation of RNA into Proteins?
What happens during Translation in Initiation ?
What happens during Translation in Initiation ?
Initiation :
Small subunits bind to the AUG start codon of the mRNA.
- A specific initiation (tRNA) carrying a methionine bind to the AUG start codon.
- Large subunits of a ribosome binds to this complex in which the tRNA occupying the P sit
Translation of RNA into Proteins?
What happens during the translation in Elongation ?
A tRNA with the complementary anti codon bonds to the mRNA occupying the A site in the ribosome A bond between the two forms a peptide bond.
- A ribosome moves one codon further away long the mRNAA translocation in the 5”3 direction A-P site .
- Empty tRNA moves from the P site to the E site
- A site is empty ready for another tRNA.
Translation of RNA into Proteins ?
What happens during the translation in Termaination
. Ribsome reaches the stop codon (UAG, UAA and UGA )
- Polypeptide is realised from the ribosome.
- tRNA is released from the ribosome .
What is Primary Transcript ?
the single-stranded ribonucleic acid product synthesized by transcription of DNA, and processed to yield various mature RNA products such as mRNAs, tRNAs, and rRNAs.
The primary transcripts designated to be mRNAs are modified in preparation for translation
The primary transcript of mRNA is then processed to remove the introns and join the remaining exons together. A mature transcript of mRNA is formed.
When does the amino acid activation occur ?
after its been spliced
Each amino acid attached to tRNA with the help of specific enzyme and ATP
What is one important thing in the presence of introns ?
That a single gene can encode for more than one kind of polypeptide .
