Adenine complementary pairs to what other bases in DNA and RNA?
Cytosine
Guanine
Thymine
Uracil
What direction does the coding strand run in?
5' to 3'
3' to 5'
What direction does the template strand run in?
What is the correct process of DNA replication?
DNA helicase unwinds -> SSBP -> Primase -> DNA polymerase builds new DNA strand in 5' to 3' -> exonuclease removes primers -> DNA polymerase fills the gaps -> DNA ligase fixes gap in sugar-phosphate backbone.
DNA helicase unwinds -> SSBP -> Primase -> DNA polymerase builds new DNA strand in 3' to 5' -> exonuclease removes primers -> DNA polymerase fills the gaps -> DNA ligase fixes gap in sugar-phosphate backbone.
DNA gyrase unwinds -> SSBP -> Primase -> DNA polymerase builds new DNA strand in 5' to 3' -> exonuclease removes primers -> DNA polymerase fills the gaps -> DNA ligase fixes gap in sugar-phosphate backbone.
DNA gyrase unwinds -> SSBP -> Primase -> DNA polymerase builds new DNA strand in 3' to 5' -> exonuclease removes primers -> DNA ligase fills the gaps -> DNA ligase fixes gap in sugar-phosphate backbone.
What is the function of Gyrase?
Prevent DNA supercoiling
Unwind the double stranded DNA
Remove RNA primers
Add DNA repeats to the 3' end of DNA strands in telomere regions (at the end of the chromosome)
What is the function of telomerase?
Prevents DNA supercoiling
Unwinds the DNA double strand
Which type of RNA encodes the amino acid sequence of a polypeptide?
mRNA
rRNA
tRNA
snRNA
Which type of RNA forms a protein complex which aid in the formation of a spliceosome?
Which type of RNA is a component of the ribosome?
Which type of RNA is responsible for bringing amino acids to the ribosomes during translation?
What does label 1 show on the model of the gene?
Promoter
RNA coding sequence
Terminator
What does label 2 show on the model of the gene?
What does label 3 show on the model of the gene?
The process of transcription is what?
DNA Helicase unwinds -> Gyrase alleviates supercoiling -> RNA polymerase binds to the promoter and starts in 5' to 3' -> Terminator is reached -> pre-mRNA is cleaved off -> DNA helix is reformed.
DNA Helicase unwinds -> Telomerase alleviates supercoiling -> RNA polymerase binds to the promoter and starts in 5' to 3' -> Terminator is reached -> pre-mRNA is cleaved off -> DNA helix is reformed.
DNA Helicase unwinds -> Gyrase alleviates supercoiling -> RNA polymerase binds to the promoter and starts in 3' to 5' -> Terminator is reached -> pre-mRNA is cleaved off -> DNA helix is reformed.
DNA Helicase unwinds -> Telomerase alleviates supercoiling -> RNA polymerase binds to the promoter and starts in 3' to 5' -> Terminator is reached -> pre-mRNA is cleaved off -> DNA helix is reformed.
Splicing occurs in both prokaryotic and eukaryotic transcription.
Select the processes which occur in the nucleus
DNA replication
Transcription
Splicing
Translation
Select the process which occurs in the cytoplasm
The start codon on mRNA is always what set of bases?
ATG
TAC
AUG
AGU
The 40s subunit of an 80s ribosome contains the P and A site where the tRNA binds.
What is the process of amino acid charging?
AA attaches to amino-acyl tRNA synthetase -> ATP binds to docking site -> hydrolysed to AMP -> AMP exits -> tRNA becomes charged -> charged tRNA is released
AA attaches to amino-acyl tRNA synthetase -> ATP binds to docking site -> hydrolysed to ADP -> ADP exits -> tRNA becomes charged -> charged tRNA is released
What is the process of translation?
Methionine-tRNA's anticodon UAC binds to the AUG sequence on mRNA -> Ribosome clamps to mRNA strand -> Peptide bond formation via Peptidyl transferase -> continuation -> STOP codon is reached -> release factor binds (no tRNA with anticodon) -> peptidyl transferase causes final protein to be ejected -> machinery disassembles
Methionine-tRNA's anticodon AUG binds to the UAC sequence on mRNA -> Ribosome clamps to rRNA strand -> Peptide bond formation via Peptidyl transferase -> continuation -> STOP codon is reached -> release factor binds (no tRNA with anticodon) -> peptidyl transferase causes final protein to be ejected -> machinery disassembles
Methionine-tRNA's anticodon AUG binds to the UAC sequence on mRNA -> Ribosome clamps to mRNA strand -> Peptide bond formation via Peptidyl transferase -> continuation -> STOP codon is reached -> release factor binds (no tRNA with anticodon) -> peptidyl transferase causes final protein to be ejected -> machinery disassembles
Methionine-tRNA's anticodon UAC binds to the AUG sequence on mRNA -> Ribosome clamps to mRNA strand -> Peptide bond formation via aminoacyl transferase -> continuation -> STOP codon is reached -> release factor binds (no tRNA with anticodon) -> peptidyl transferase causes final protein to be ejected -> machinery disassembles
Convention is that polypeptides start with a C terminus and end with an N terminus.
Polysomes are advantageous because they mean mRNA, which is very unstable, can be translated into many proteins despite having a short life span.
What are the three generic types of DNA mutations?
Insertion
Substitution
Deletion
Rearrangement
Reorderment
What is meant by a silent mutation?
The same amino acid is coded for, because although the base is substituted for a different one, the codon still codes for the same amino acid due to the degenerate nature of the triplet code.
A different amino acid is coded for for that particular triplet but the protein itself still remains functional.
A premature STOP codon is coded for by the substitution which leads to a truncated,, non functional protein.
What is meant by a missense mutation?
What is meant by a nonsense mutation?
Deletion or insertion of 1,2,4 or 5 bases could cause a frameshift
A frameshift can completely alter the primary structure of a protein.
Most intronic mutations are not detrimental to the final protein.
A missense mutation can produce a partially working protein.