What name is given to the process in which a strand of DNA is used as a template for the manufacture of a strand of pre-mRNA?
transcription
What name is given to the process in which the information encoded in a strand of mRNA is used to construct a protein?
translation
What name is given to the process in which pre-mRNA is edited into mRNA?
RNA processing
Polypeptides are assembled from _____.
amino acids
RNA processing converts the RNA transcript into _____.
mRNA
What is the process called that converts the genetic information stored in DNA to an RNA copy?
transcription
DNA does not store the information to synthesize which of the following?
Organelles
Transcription begins at a promoter. What is a promoter?
A site in DNA that recruits the RNA Polymerase
Which of the following statements best describes the promoter of a protein-coding gene?
The promoter is a nontranscribed region of a gene.
What determines which base is to be added to an RNA strand during transcription?
Base pairing between the DNA template strand and the RNA nucleotides
Which of the following terms best describes the relationship between the newly synthesized RNA molecule and the DNA template strand?
Complementary
What happens to RNA polymerase II after it has completed transcription of a gene?
It is free to bind to another promoter and begin transcription.
During RNA processing a(n) _____ is added to the 5' end of the RNA.
modified guanine nucleotide
During RNA processing a(n) _____ is added to the 3' end of the RNA.
a long string of adenine nucleotides
Spliceosomes are composed of _____.
small RNAs and proteins
The RNA segments joined to one another by spliceosomes are _____.
exons
Translation occurs in the _____.
cytoplasm
Where does translation take place?
Ribosome
Which nucleic acid is translated to make a protein?
mRNA
Which of the following processes is an example of a post-translational modification?
Phosphorylation
Which of the following steps occurs last in the initiation phase of translation?
The large ribosomal subunit joins the complex.
At which site do new aminoacyl tRNAs enter the ribosome during elongation?
A-site
What is meant by translocation?
The ribosome slides one codon down the mRNA.
True or false. A tRNA with an anticodon complementary to the stop codon catalyzes the reaction by which translation is terminated.
False
Which of these is a tRNA?
b
What enzyme catalyzes the attachment of an amino acid to tRNA?
aminoacyl-tRNA synthetase
The tRNA anticodon, GAC, is complementary to the mRNA codon with the sequence _____.
CUG
What is the name of the process shown in the diagram?
initiation (of translation)
The initiator tRNA attaches at the ribosome's _____ site.
p
____________ of translation happens when the ribosome hits a stop codon on the mRNA.
termination
2. Amino acids are attached to tRNA by enzymes called
aminoacyl-tRNA synthetase.
3. The RNA that has an amino acid attached to it, and that binds to the codon on the mRNA, is called a .
tRNA
The process, performed by the ribosome, of reading mRNA and synthesizing a protein is called .
_______-
translation
_______ of translation always happens at the start codon of the mRNA.
initiation
True or false? A codon is a group of three bases that can specify more than one amino acid.
false
Which of the following statements about mutations is false?
A knock-out mutation results in a total absence of the mutated protein.
If a DNA sequence is altered from TAGCTGA to TAGTGA, what kind of mutation has occurred?
Deletion
Which mutation(s) would not change the remainder of the reading frame of a gene sequence that follows the mutation(s)?
One addition and one deletion mutation.
If the sequence ATGCATGTCAATTGA were mutated such that a base were inserted after the first G and the third T were deleted, how many amino acids would be changed in the mutant protein?
Two
If a mutated DNA sequence produces a protein that differs in one central amino acid from the normal protein, which of the following kinds of mutations could have occurred?
An addition mutation and a deletion mutation.
Use the codon table to determine which mRNA triplets code for the amino acid cysteine, Cys.
UGU, UGC
Think about the DNA coding sequence of a gene. If an A were swapped for a T, what kind of mutation could it cause and why?
It could cause a silent, missense, or nonsense mutation because those are the types that can be caused by a nucleotide-pair substitution like this one.
Why is a frameshift missense mutation more likely to have a severe effect on phenotype than a nucleotide-pair substitution missense mutation in the same protein?
A substitution missense affects only one codon, but a frameshift missense affects all codons downstream of the frameshift.
Which of the following sequences shows a frameshift mutation compared to the wild-type mRNA sequence?
wild-type
5'-AUGCAUACAUUGGAGUGA-3'
mutant
5'-AUGCAUACAUCUGGAGUGA-3'
A _________ mutation causes a wild-type amino acid to be replaced by a different amino acid.
missense
A ___________ mutation causes an early Stop codon to occur.
nonsense
A ___________ mutation does not change the wild-type amino acid sequence.
silent
Suppose that the triplet of nucleotides indicated in bold (AGC) spans two codons, that is, CTA and GCC. If the triplet AGC were deleted from this DNA coding sequence, what effect would it have on the resulting protein?
The two flanking codons would be altered, but the rest of the amino acid sequence would be the same because there would be no frameshift.