Quiz Questions Flashcards
Imagine a segment of DNA (within a gene) encoding a certain amount of information in its
nucleotide sequence. When this segment is fully transcribed into mRNA and then translated into
protein, in general,
꙱ A. the protein sequence would carry more information compared to the DNA and mRNA
sequences, because its alphabet has 20 letters.
꙱ B. the protein sequence would carry less information compared to the DNA and mRNA
sequences, because several codons can correspond to one amino acid.
꙱ C. the amount of information in the mRNA sequence is lower, because the mRNA has been
transcribed using only one of the DNA strands as the template.
꙱ D. the amount of information in the mRNA sequence is higher, because several mRNA
molecules can be transcribed from one DNA molecule
꙱ A. the protein sequence would carry more information compared to the DNA and mRNA
sequences, because its alphabet has 20 letters.
꙱ B. the protein sequence would carry less information compared to the DNA and mRNA
sequences, because several codons can correspond to one amino acid.
꙱ C. the amount of information in the mRNA sequence is lower, because the mRNA has been
transcribed using only one of the DNA strands as the template.
꙱ D. the amount of information in the mRNA sequence is higher, because several mRNA
molecules can be transcribed from one DNA molecule
Based on the variation of genome size and gene number in the organisms presented in the
following graph, which organism has the highest number of genes per unit length of their
genome? (Note the logarithmic scale.)
꙱ A. H. sapiens ꙱ B. M. musculus ꙱ C. A. thaliana ꙱ D. C. elegans ꙱ E. E. coli
Indicate if each of the following descriptions matches RNA (R) or DNA (D). Your answer would
be a five-letter string composed of letters R and D only, e.g. RDDRR.
( ) It is mainly found as a long, double-stranded molecule.
( ) It contains the sugar ribose.
( ) It normally contains the bases thymine, cytosine, adenine, and guanine.
( ) It can normally adopt distinctive folded shapes.
( ) It can be used as the template for protein synthesis.
d
It is a model organism used to study various cell processes such as regulation of the eukaryotic
cell cycle. Mutants are available for every gene in its exceptionally small genome. It can live
indefinitely in either a haploid or a diploid state. Which of the following describes this organism?
꙱ A. It can reproduce only asexually. ꙱ B. It is a fungus. ꙱ C. It lacks a cell wall. ꙱ D. Its cell cycle is typically much slower than that of human cells. ꙱ E. All of the above
꙱ A. It can reproduce only asexually. ꙱ B. It is a fungus. ꙱ C. It lacks a cell wall. ꙱ D. Its cell cycle is typically much slower than that of human cells. ꙱ E. All of the above
Didinium nasutum is a single-celled eukaryote that can hunt and feed on other living cells. It has
an elaborate anatomy with beating cilia, a “mouth opening,” an “anal aperture,” and a set of
contractile bundles; it can also shoot “darts” to paralyze its prey. What group of living cells does
D. nasutum represent?
꙱ A. Protozoa ꙱ B. Yeasts ꙱ C. Algae ꙱ D. Animals ꙱ E. It can belong to any of the above
꙱ A. Protozoa ꙱ B. Yeasts ꙱ C. Algae ꙱ D. Animals ꙱ E. It can belong to any of the above
Which of the following represents an “activated” carrier molecule? ꙱ A. AMP ꙱ B. NADH ꙱ C. NAD+ ꙱ D. NADP+ ꙱ E. CoA
꙱ A. AMP ꙱ B. NADH ꙱ C. NAD+ ꙱ D. NADP+ ꙱ E. CoA
Many viruses have large capsids in the form of a hollow sphere, made of hundreds of identical
protein subunits. What are the advantages of having coats made of several copies of only a few
subunits?
꙱ A. Assembly can be readily regulated.
꙱ B. Disassembly can be readily regulated.
꙱ C. It requires a smaller amount of genetic information.
꙱ D. The effect of mistakes in protein synthesis on the overall assembly is minimized.
꙱ E. All of the above.
꙱ A. Assembly can be readily regulated.
꙱ B. Disassembly can be readily regulated.
꙱ C. It requires a smaller amount of genetic information.
꙱ D. The effect of mistakes in protein synthesis on the overall assembly is minimized.
꙱ E. All of the above.
Which of the regulatory interactions 1 to 5 depicted in the following diagram is NOT an example
of a negative feedback regulation?
꙱ 1. ꙱ 2. ꙱ 3. ꙱ 4. ꙱ 5.
A viral version of the Src kinase called v-Src is found in some retroviruses. Unlike the cellular
Src, the v-Src kinase is constitutively active, and can drive the cell into uncontrolled growth and
tumor formation. Which of the following molecular differences between the two versions of Src is
more likely to be responsible for this?
꙱ A. v-Src lacks the active-site tyrosine residue.
꙱ B. v-Src lacks a lobe of the kinase domain.
꙱ C. v-Src has multiple inhibitory tyrosine phosphorylation sites in the kinase domain.
꙱ D. v-Src lacks the C-terminal tail that can bind to Src’s SH2 domain.
꙱ E. v-Src has a longer C-terminal tail.
꙱ A. v-Src lacks the active-site tyrosine residue.
꙱ B. v-Src lacks a lobe of the kinase domain.
꙱ C. v-Src has multiple inhibitory tyrosine phosphorylation sites in the kinase domain.
꙱ D. v-Src lacks the C-terminal tail that can bind to Src’s SH2 domain.
꙱ E. v-Src has a longer C-terminal tail.
Due to their high transcription rate, active ribosomal RNA (rRNA) genes can be easily
distinguished in electron micrographs of chromatin spreads. They have a characteristic
“Christmas tree” appearance, where the DNA template is the “trunk” of the tree and the nascent
RNA transcripts form closely packed “branches.” At the base of each branch is an RNA
polymerase extending that branch, while RNA processing complexes at the tip of the branch
form terminal “ornaments.” The top of the tree represents the of the rRNA gene, and the
“ornaments” are at the end of the nascent rRNA molecules.
꙱ A. end; 3’
꙱ B. end; 5’
꙱ C. beginning; either 3’ or 5’
꙱ D. beginning; 3’
꙱ E. beginning; 5’
꙱ A. end; 3' ꙱ B. end; 5' ꙱ C. beginning; either 3' or 5' ꙱ D. beginning; 3' ꙱ E. beginning; 5'
