|
|
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
14 May 2023, 20:00
Kudos
Bookmarks
Question 1
C
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
25%
(medium)
Question Stats:
67% (02:40) correct
33%
(02:52) wrong
based on 143
sessions
History
Date
Time
Result
Not Attempted Yet
Question 2
C
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
55%
(hard)
Question Stats:
50% (01:11) correct 50%
(01:23) wrong
based on 133
sessions
History
Date
Time
Result
Not Attempted Yet
For many years, biological scientists have sought to decipher cellular function by quantifying the degrees of protein and mRNA expression within populations of their cells of interest. Classically, these measurements required combining many cells into a single sample and rupturing their membranes, thus exposing pooled quantities of the target molecule for detection. One limitation of these techniques is the reliance on average measurements: it is impossible to distinguish a uniform population of cells expressing intermediate quantities of a molecule from a population composed of separate low and high expressers. The distinction has proven to be important, particularly in the context of drug targeting of cancer cells; prescribing a dose to hit the “average” cell may completely miss the more aggressive “one percent.
”The advent of single-cell measurement technology such as flow cytometry and RNA FISH has made it possible to capture not only a population’s average levels of a molecule, but also the distribution of the molecule’s expression within the population. As a result, researchers are increasingly investigating the sources and significance of variability within populations that were previously assumed to be identical.
”The advent of single-cell measurement technology such as flow cytometry and RNA FISH has made it possible to capture not only a population’s average levels of a molecule, but also the distribution of the molecule’s expression within the population. As a result, researchers are increasingly investigating the sources and significance of variability within populations that were previously assumed to be identical.
1. According to the passage, the limitation of combining many cells into one sample and then rupturing their membranes in order to detect a target molecule is that
(A) variability exists within cell populations
(B) some cells in the sample may contaminate others
(C) this method cannot single out the cells that express more of a certain molecule
(D) the rupture of cell membranes is implicated in the formation of cancer
(E) it is preferable to capture a population’s average levels of a molecule
(A) variability exists within cell populations
(B) some cells in the sample may contaminate others
(C) this method cannot single out the cells that express more of a certain molecule
(D) the rupture of cell membranes is implicated in the formation of cancer
(E) it is preferable to capture a population’s average levels of a molecule
2. Which of the following can be inferred from the passage regarding flow cytometry and RNA FISH?
I. Both technologies allow researchers to quantify properties of individual cells.
II. Using these technologies, it is impossible to distinguish a uniform population of cells expressing intermediate quantities of a molecule.
III. Both technologies allow researchers to measure variability of molecule expression within cell populations.
A. I Only
B. III Only
C. I and III Only
D. II and III Only
E. I, II, and III
I. Both technologies allow researchers to quantify properties of individual cells.
II. Using these technologies, it is impossible to distinguish a uniform population of cells expressing intermediate quantities of a molecule.
III. Both technologies allow researchers to measure variability of molecule expression within cell populations.
A. I Only
B. III Only
C. I and III Only
D. II and III Only
E. I, II, and III
RC Butler 2023 - Practice Two RC Passages Everyday.
Passage # 147 Date: 15-May-2023
This question is part of RC Butler 2023. Click here for Details
Passage # 147 Date: 15-May-2023
This question is part of RC Butler 2023. Click here for Details
Manhattan GRE 5lb.
02 Aug 2023, 10:55
Kudos
Bookmarks
mitul19
Official Explanation
2. Which of the following can be inferred from the passage regarding flow cytometry and RNA FISH?
Explanation
According to the second paragraph, flow cytometry and RNA FISH are examples of “single-cell measurement technology,” so the first statement is true. Much of the wording in the second statement—“it is impossible to distinguish a uniform population of cells expressing intermediate quantities of a molecule”—is lifted from a sentence in the first paragraph, talking about classical methods—not the newer, single celled measurement technologies. Finally, the second paragraph states that flow cytometry and RNA FISH have “made it possible to capture … the distribution of the molecule’s expression within the population,” which is a good match for the wording in the third statement.
Answer: C
Explanation
According to the second paragraph, flow cytometry and RNA FISH are examples of “single-cell measurement technology,” so the first statement is true. Much of the wording in the second statement—“it is impossible to distinguish a uniform population of cells expressing intermediate quantities of a molecule”—is lifted from a sentence in the first paragraph, talking about classical methods—not the newer, single celled measurement technologies. Finally, the second paragraph states that flow cytometry and RNA FISH have “made it possible to capture … the distribution of the molecule’s expression within the population,” which is a good match for the wording in the third statement.
Answer: C
