The Ames test is used to identify potential carcinogens. A compound tested resulted in a few scattered colonies growing on the media, similar to the control plate with no disk. What does this result imply?
A. The compound in the disk is so toxic that it inhibits almost all growth on the plate.
B. The few colonies that grew are resistant to the compound.
C. The few colonies that grew contain reversion mutations that allow them to grow on media without histidine.
D. The compound in the disk is not mutagenic so there was no increase in the reversion rate.
E. Either the compound in the disk is not mutagenic or the few colonies that grew contain reversion mutations.
Artificial chromosomes that will be stable in human cells must include:
A. a yeast centromere.
B. human telomeres.
C. a multiple cloning site.
D. human centromeres, telomeres, and origins of replication.
E. yeast centromeres and telomeres, as well as human origins of replication.
Efficiently translated mRNAs tend to be stable in the cytoplasm; those that are poorly translated tend tobe rapidly degraded. Which of the following is not a step in the pathway for mRNA degradation?
A. targeting of upstream ORFs for nuclease binding
B. removal of the poly(A) tail
C. removal of the 5' 7-meG cap
D. binding of mRNA by 5'-3' and 3'-5' RNA exonucleases
Which of the following is an intermediate in the reaction that forms Ala-tRNA?
A. Alanyl-ATP
B. Alanyl-ADP
C. Alanyl-PPi
D. Alanyl-AMP
Select all answers that describe the reagents required for reversible terminator sequencing.
A. dATP, dGTP, dCTP, and dTTP with the same fluorescent label
B. dATP, dGTP, dCTP, and dTTP with different fluorescent labels
C. dATP, dGTP, dCTP, and dTTP with a blocking group on the 5' end
D. dATP, dGTP, dCTP, and dTTP with a blocking group on the 3' end
E. dideoxy forms of dATP, dGTP, dCTP, and dTTP, which are used sequentially
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