Card Set Information
BIOL Protein Synthesis
Study Cards for Protein Synthesis BIOL 189 CSN
What functions as an intermediary between DNA and protein synthesis?
Name the three types of RNA discussed in class.
messenger RNA (mRNA)
transfer RNA (tRNA)
ribosomal RNA (rRNA)
What is the function of mRNA?
to carry the genetic message from the nucleus to the protein factory of the cell
What is the function of tRNA?
to interpret mRNA and bring amino acids to the growing peptide chain
Which type of RNA is most abundant?
The type of RNA that picks up amino acids, brings them to the ribosome, and adds them to the growing protein is:
The RNA that is a recipe for protein is:
What occurs during transcription?
DNA is used as a template to make mRNA
What occurs during translation?
mRNA is decoded to form amino acid chains (proteins)
What are the two properties of our genetic code?
the code must be unambiguous
the code must be redundant
Three base pairs on a strand of mRNA are known as a:
A codon corresponds to what?
an amino acid
The fact that each codon only codes for one amino acid is an example of how our genetic code is:
The fact that several codons can correspond to a single amino acid is an example of how our genetic code is:
True or False - Some codons act as signals.
What two things does the codon AUG code for?
UAA, UAG, and UGA all code for:
Where does transcription occur?
in the nucleus
What role does the promoter region play in transcription?
it initiates transcription
The point of transcription intiation is known as the:
The TATA box is part of the:
The TATA box is recognized by:
Transcription factors bind to the DNA strand at the TATA box and help what other enzyme bind to the DNA strand?
RNA polymerase II
What is the function of RNA polymerase II?
to pull apart the DNA strand and add RNA complimentary base pairs
Which strand of parent DNA is the template for transcription?
the 3' to 5' strand
In which direction does RNA form?
5' to 3'
True or False - After the RNA strand forms, the DNA strands will reform a double helix.
Why does transcription stop in bacteria?
a terminator causes the RNA to detach from the template strand
Why does transcription stop in eukaryotes?
RNA poly II transcribes the polyadenylation sequence
AAUAAA codes for what?
the polyadenylation sequence
After transcribing the polyadenylation sequence, 30 nucleotides later the mRNA is:
True of False - Following the termination of transcription the resulting RNA leaves the nucleus for the ribosomes.
False - the pre-mRNA must first be processed
What is added to the 5' prime end of pre-mRNA?
a modified guanine cap
What is the function of the modified guanine cap added to pre-mRNA?
It is a signal site for ribosome binding
What is added to the 3' end of pre-mRNA?
a poly-A tail
What is a poly-A tail?
a chain of 150-200 adenines
What is the function of the poly-A tail?
helps transport the mRNA out of the nucleus
What is the structure of pre-mRNA?
sequence of nucleotides comprised of exons and introns
Which codes for amino acids, exons or introns?
True or False - Introns code for specific amino acids.
False - introns don't code for anything
The molecule that clips out the introns and splices together exons is:
Spliceosomes are comprised of:
Which parts of pre-mRNA must be removed before it can be sent to the ribosomes, exons or introns?
Where does translation occur?
What shape is tRNA?
What is the function of aminoacyl-tRNA Synthetase?
to attach the correct amino acid to a tRNA
Aminoacyl-tRNA synthetase requires an amino acid and what molecule?
How does tRNA bond to an amino acid?
A tRNA molecule that is bound to an amino acid is known as:
How many amino acids do humans have in their body?
How many types of aminoacyl-tRNA synthetase do humans have in their body?
tRNA have three nucleotides that correspond to the three nucleotides of an mRNA codon called an:
How many codon combinations are there?
How many types of tRNA are there?
True or False - Some tRNA molecules can bind with more than one codon.
The flexibility in the 3rd base pair that allows some tRNA to bind with multiple codons is known as:
What role does the ribosome play in protein synthesis?
it is the site of protein synthesis or assembly
Which subunit of a ribosome, small or large, has an mRNA binding site?
the small subunit
Where does the small subunit bind with the mRNA?
just upstream of the start codon
List the three sites on the large ribosomal subunit.
the A site
the P site
the E site
What is the function of the A site?
site where tRNA enters to add the next amino acid
What is the function of the P site?
site that contains the tRNA with the growing protein chain
What is the function of the E site?
tRNA exit site
When the large subunit attaches to the small subunit it completes the:
translation initiation complex
What binds to the start codon to begin translation?
a tRNA initiator
What kind of bond links the amino acids within the developing protein?
a peptide bond
When the amino acid from the tRNA is joined to the peptide chain, the amino acid chain is actually shifted from the ____ site to the ____ site.
P site to the A site
When the stop codon is read, what enters the A site?
What are the two primary functions of release factors?
release protein chain from the tRNA
break apart the ribosome
Describe a silent mutation.
a mutation with no physiological effect on the individual
A mutation with no visible effect on an organism is a/an:
This type of mutation changes an entire amino acid.
Describe a missense mutation.
a mutation that changes an entire amino acid
What disease discussed in class is the result of a missense mutation?
Describe a nonsense mutation.
occurs when an amino acid codon is replaced with a stop codon
When an amino acid is replaced in the mRNA strand with a stop codon you have this type of mutation.
True or False - Insertions and deletions have minor effects on protein synthesis.
False - they have major effects
Adding base pairs to an mRNA results in what type of mutation?
Removing base pairs from an mRNA, and thus changing the entire codon sequence, is known as a _______ mutation.
When protein synthesis is stopped prematurely, it is most likely due to a _________ mutation.