7: RNA & the Genetic Code
Terms in this set (71)
Messenger RNA is synthesized in the
5' to 3' direction
Messenger RNA is complementary and
anti-parallel to the DNA template strand
The ribosome translates the mRNA in the ______ direction
5' to 3'
the formation of an RNA strand complementary to the DNA strand by RNA polymerase
The DNA coding strand is ____ to the mRNA
The DNA coding strand is
5' to 3'
The DNA template strand is
3' to 5'
The process to create a protein from an mRNA transcript is called
the information specifying the amino acid sequence of hte protein to the ribosome
What transcribes mRNA from the DNA template strand?
Where does mRNA transcription occur?
The coding pattern of eukaryotes in which one mRNA molecule codes for only one protein.
The coding pattern of prokaryotes, in which one mRNA may code for multiple proteins.
mRNA takes the information
from the DNA to ribosomes
tRNA is responsible for
converting the language of nucleic acids to the language of amino acids and peptides
Each tRNA molecule includes a 3 nucleotide
tRNA is found where in the cell?
Each tRNA is
activated by a different aminoacyl-tRNA synthetase
Each aminoacyl-tRNA requires
2 high-energy bonds from ATP
Each tRNA has a
CCA nucleotide sequence where the amino acid binds
What is the high-energy aminoacyl-tRNA bond used for?
supply the energy needed to create a peptide bond during translation
Where is rRNA synthesized?
Many rRNA molecules function
rRNA helps catalyze the formation
of peptide bonds
All codons are written in which direction?
5' to 3'
A mutation that changes a single nucleotide, but does not change the amino acid created.
A base-pair substitution that results in a codon that codes for a different amino acid.
A mutation that changes an amino acid codon to one of the three stop codons, resulting in a shorter and usually nonfunctional protein.
gene mutation in which a single base pair in DNA has been changed
the three nucelotides of a codon
mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide
DNA cannot leave
RNA synthesizes genes by searching for
specialized DNA regions known as promoters
What is the main player in transcribing mRNA?
RNA polymerase II
Which is the binding site for RNA polymerase II
the TATA box
Why is the TATA box named as such?
high concentration of adenine and thymine
RNA polymerase does not require what to start generating a transcript?
RNA Polymerase I is located where?
RNA Polymerase I synthesizes what?
RNA Polymerase II is located where?
RNA Polymerase II synthesizes what?
hnRNA and some snRNA
RNA Polymerase III is located where?
RNA Polymerase III synthesizes what?
tRNA and some rRNA
RNA does not
heterogenous nuclear RNA
Precursor mRNA, which must be processed before it becomes mRNA and leaves the nucleus; processing involves splicing, capping on the 5' end, and adding a repeat adenine chain (poly A) on the 3' end
A large complex made up of proteins and RNA molecules that splices RNA by interacting with the ends of an RNA intron, releasing the intron and joining the two adjacent exons.
The 5' cap protects
the mRNA from degradation in the cytoplasm
The longer the poly-A tail
the more time the mRNA will be able to survive before being digested in the cytoplasm
stay in the nucleous
exit the nucleus as part of the mRNA
Mutations in splice sites can lead to
Name this process: DNA -> DNA
Name this process: DNA --> RNA
Name this process: RNA--> Protein
The shine-delgarno sequence is specific to
An enzyme that catalyzes the reaction in which an amino acid is cleaved from the tRNA in the P site of the ribosome and forms a peptide bond with the amino acid on the tRNA in the A site of the ribosome.
Why are peptides phosphorylated?
to activate or deactive proteins
Why are peptides carboxylated?
to serve as calcium binding sites
Why are peptides glycosylated?
to serve as tags providing cellular destination for the protein
What is prenylation>
the addition of lipid groups
What is the purpose of prenylation?
facilitate attachment to cell membranes
The chemical bond that forms between the carboxyl group of one amino acid and the amino group of another amino acid
A specialized structure in the nucleus, formed from various chromosomes and active in the synthesis of ribosomes
Where is tRNA synthesized?
allow for the control of one gene's expression by multiple signals
require the presence of an inducer to transcribe, repressor binds to the operator, prevents RNA polymerase from transcribing structural genes. An inducer must attach to the repressor for transcription to occur
Negative Control Mechanism
Binding of protein reduces transcriptional activity
A classic example of an inducible system is the
Positive Control Mechanism
Binding of a molecule increases transcriptional activity
A system that is normally "turned on" but can be inactivated by the addition of a repressor or a corepressor.
A classic example of a repressible system is the