Chapter 7 -> From DNA to Proteins Flashcards
What is the Central Dogma of Molecular Biology?
DNA gets transcribed into RNA which then gets translated into Proteins
What is the basic definition of Transcription?
The copying of the nucleotide sequence into Messenger RNA
What is the basic definition of Translation?
mRNA get translated into proteins
What are the three differences between DNA and RNA?
1) DNA is Double stranded, RNA is Single stranded
2) DNA has the sugar Deoxyribose, while RNA has the sugar Ribose
3) DNA has Thymine as a base, RNA has Uracil as a base
Transcription:
1) _______ _________ binds to, opens, and unwinds the DNA helix then copies one strand of DNA into RNA
Transcription only occurs in areas of the DNA where there are ______
2) Specific sequences of nucleotides AKA ________ allow RNA Polymerase to bind at these location next to genes
3) Proteins called __________ ________ help RNA polymerase find the promoter and bind to the DNA
4) RNA Polymerase binds to promoter then separates DNA strands then proceeds in the direction __ prime to __ prime, copying the DNA strand
5) When RNA Polymerase reaches the end of a gene, it encounters what is known as a ________ ________
6) RNA Polymerase and mRNA are then released from the DNA molecule
* Multiple copies of mRNA can be synthesized during transcription*
Messenger RNA Processing:
Primary Transcript -> Pre-mRNA is immature and not fully functional -> Transcripts undergo a series of modifications in the nucleus before they are ready for protein synthesis (listed below)
1) RNA Splicing -> Genes consist of _____ and ______. Which one is used for protein coding sequencing?
2) Introns are removed and exons are spliced together before protein synthesis can occur
2) 5’ cap is added
3) Polyadenylation occurs
1) RNA Polymerase
Genes
2) Promoters
3) Transcription Factors
4) 5 to 3
5) Termination Sequence
1) Introns and Exons. Exons
Transcription again but different wording
1) ______ _________ binds to a promoter sequence
2) ________ _______ aid the binding of RNA Polymerase
3) RNA Polymerase then opens the helix to allow it access to the coding strand of DNA
4) RNA Polymerase _______ the coding strand information into a single strand mRNA
5) RNA Polymerase continues to transcribe until it encounters a _________ _______ on the DNA coding strand
6) RNA Polymerase is then released from the DNA coding strand
7) The mRNA primary transcript now must be processed
8) Exons are removed by the ___________
9) __ cap is added
10) ____________ occurs at the 3’ end
11) The mature RNA is now ready to be transported out of the nucleus and into the cytoplasm where translation can occur!
1) RNA Polymerase
2) Transcription Factors
4) Transcribes
5) Termination Sequence
8) Spliceosome
9) 5’
10) Polyadenylation
Where does translation occur?
Occurs in the cytoplasm
List the three types of RNA used in the process of translation
mRNA, rRNA, and tRNA- tRNA transports amino acids to the ribosome during protein synthesis
What are the four bases in mRNA molecules?
A, U, G, and C
How many potential codons can be made from the 4 bases?
64
What is the start codon sequence and what does it do?
AUG- it tells ribosomes where to start translation and it codes for methionine
What are the stop codons that terminate translation?
UAA, UAG, and UGA
What are the three stages of translation in eukaryotes?
Initiation, Elongation, and Termination
Translation Summary
1) Mature RNA exits the nucleus and travels to a ribosome
2) Initiation-> small subunit of the ribosome find the _ cap, attaches to mRNA aided by initiation factors, and reads sequence to located start codon
3) Initiator tRNA anticodon ____ binds to _____ start codon
4) Large ribosome subunit now binds to small subunit, mRNA, tRNA, transcription factor complex forming __, __, and __ binding sites
5) Elongation-> the ribosome slides forward on the mRNA, next tRNA enters the ribosome, binding at the anticodon in the A site
6) Peptidyl transferase forms the peptide bond between the first amino acid and the second amino acid
7) Ribosome slides forward 1 codon, initiator tRNA is now released from the E site
Third tRNA enter and binds to A site
8) Termination-> Elongation process continues until a stop codon is reached where a releasing factor binds to A site
9) Ribosome move forward causing disassociation of the large and small subunits of the ribosome
2) 5’
3) UAC AUG
4) A, P, E
Ribosomes consist of _______ and proteins and have two subunits, large and small
rRNA
