Events & Promotions
|
|
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.
Nov 2007:30 AM PST
-08:30 AM PST
Learn what truly sets the UC Riverside MBA apart and how it helps in your professional growth
Nov 2211:00 AM IST
-01:00 PM IST
Do RC/MSR passages scare you? e-GMAT is conducting a masterclass to help you learn – Learn effective reading strategies Tackle difficult RC & MSR with confidence Excel in timed test environment- Nov 23
11:00 AM IST
-01:00 PM IST
Attend this free GMAT Algebra Webinar and learn how to master the most challenging Inequalities and Absolute Value problems with ease. 
Nov 2510:00 AM EST
-11:00 AM EST
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors.
07 Apr 2025, 00:30
Kudos
Bookmarks
E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
65%
(hard)
Question Stats:
61% (02:15) correct
39%
(02:12)
wrong
based on 313
sessions
History
Date
Time
Result
Not Attempted Yet
When the nineteenth-century German bacteriologist Robert Koch identified a particular bacterium as responsible for cholera, Max von Pettenkoffer, a physician, expressed his skepticism by voluntarily drinking an entire bottle of the allegedly responsible bacteria. Although von Pettenkoffer took his failure to come down with the disease as a refutation of Koch's hypothesis that cholera was caused by bacteria, Koch argued that von Pettenkoffer had been protected by his own stomach acid. The acid secreted by the stomach, Koch explained, kills most ingested bacteria.
Which of the following, if true, provides the most evidence to support Koch's counterargument?
A. Peptic ulcers, often associated with excessive secretions of stomach acid, are common in certain areas characterized by low rates of cholera.
B. As von Pettenkoffer later admitted that he had previously had cholera, it is probable that he had developed antibodies that protected him from a second attack.
C. Cholera is endemic in areas in which poor sanitation results in high concentrations of cholera bacteria in drinking water.
D. Although stomach acid kills most ingested bacteria, large numbers of e. coli bacteria nonetheless manage to make their way to the lower intestine of the digestive tract.
E. Cholera bacteria ingested with bicarbonate of soda, a neutralizer of stomach acid, is more likely to result in cholera than if the bacteria is ingested alone.
Which of the following, if true, provides the most evidence to support Koch's counterargument?
A. Peptic ulcers, often associated with excessive secretions of stomach acid, are common in certain areas characterized by low rates of cholera.
B. As von Pettenkoffer later admitted that he had previously had cholera, it is probable that he had developed antibodies that protected him from a second attack.
C. Cholera is endemic in areas in which poor sanitation results in high concentrations of cholera bacteria in drinking water.
D. Although stomach acid kills most ingested bacteria, large numbers of e. coli bacteria nonetheless manage to make their way to the lower intestine of the digestive tract.
E. Cholera bacteria ingested with bicarbonate of soda, a neutralizer of stomach acid, is more likely to result in cholera than if the bacteria is ingested alone.
07 Apr 2025, 11:32
Kudos
Bookmarks
Bunuel
In the nineteenth-century German bacteriologist Robert Koch identified a particular bacterium as responsible for cholera.
Max von Pettenkoffer, a physician, expressed his skepticism by voluntarily drinking an entire bottle of the allegedly responsible bacteria.
But, Max was not infected by this disease , hence used this as a refutation of Koch hypothesis that “ the identified bacterium is responsible for causing cholera “.
Robert Koch countered the argument by mentioning the stomach acids of Max has killed the bacteria. The environment inside Max stomach is not conducive for bacterial Growth.
We need to find which options strengthens the counter argument provided by Robert Koch.
A. Peptic ulcers, often associated with excessive secretions of stomach acid, are common in certain areas characterized by low rates of cholera.
We are not interested in Peptic Ulcers. Max did not contract peptic ulcers. Hence out of scope.
B. As von Pettenkoffer later admitted that he had previously had cholera, it is probable that he had developed antibodies that protected him from a second attack.
This is an interesting trap answer. If your carried away with the flow of passage. This can be true that Max has acquired immunity for cholera because of his previous infection. Antibodies have been generated in larger amounts to prevent future infection. DOESNT STRENGHTEN.
C. Cholera is endemic in areas in which poor sanitation results in high concentrations of cholera bacteria in drinking water.
OUT OF SCOPE.
D. Although stomach acid kills most ingested bacteria, large numbers of e. coli bacteria nonetheless manage to make their way to the lower intestine of the digestive tract.
No where it’s mentioned that E. coli is responsible for cholera. Hence out of scope.
E. Cholera bacteria ingested with bicarbonate of soda, a neutralizer of stomach acid, is more likely to result in cholera than if the bacteria is ingested alone.
This strengthens the counter argument of Robert that, the acids present inside the stomach are the main reason for the destruction of cholera causing bacteria in Max. Bicarbonate of soda which neutralises the stomach acid provides a fertile ground for bacterial growth.
Hence, option E
07 Apr 2025, 22:07
Kudos
Bookmarks
The passage explains the identification of bacteria which causes Cholera by Robert Koch and same was refuted by Max von Petten koffer by taking a bottle of bacteria and nothing happening to him. The same was explained by Koch that stomach acid is responsible for the digestion of the bacteria.
Analyzing the statements which supports Koch counterargument:
A. Peptic ulcers, often associated with excessive secretions of stomach acid, are common in certain areas characterized by low rates of cholera.
Peptic ulcers are out of scope. However, the option confuses with mentioning of stomach acid and low rates of cholera. Eliminate.
B. As von Pettenkoffer later admitted that he had previously had cholera, it is probable that he had developed antibodies that protected him from a second attack.
Doesn't support the counterargument. Eliminate.
C. Cholera is endemic in areas in which poor sanitation results in high concentrations of cholera bacteria in drinking water.
Factual information. Eliminate.
D. Although stomach acid kills most ingested bacteria, large numbers of e. coli bacteria nonetheless manage to make their way to the lower intestine of the digestive tract.
Stomach acid kills most bacterias but whether it is killing cholera bacteria hasn't been mentioned. Eliminate
E. Cholera bacteria ingested with bicarbonate of soda, a neutralizer of stomach acid, is more likely to result in cholera than if the bacteria is ingested alone.
It explains that stomach acid kills most of the cholera bacteria as neutralizer of acid is taken with bacteria results in cholera. Correct answer is E.
Analyzing the statements which supports Koch counterargument:
A. Peptic ulcers, often associated with excessive secretions of stomach acid, are common in certain areas characterized by low rates of cholera.
Peptic ulcers are out of scope. However, the option confuses with mentioning of stomach acid and low rates of cholera. Eliminate.
B. As von Pettenkoffer later admitted that he had previously had cholera, it is probable that he had developed antibodies that protected him from a second attack.
Doesn't support the counterargument. Eliminate.
C. Cholera is endemic in areas in which poor sanitation results in high concentrations of cholera bacteria in drinking water.
Factual information. Eliminate.
D. Although stomach acid kills most ingested bacteria, large numbers of e. coli bacteria nonetheless manage to make their way to the lower intestine of the digestive tract.
Stomach acid kills most bacterias but whether it is killing cholera bacteria hasn't been mentioned. Eliminate
E. Cholera bacteria ingested with bicarbonate of soda, a neutralizer of stomach acid, is more likely to result in cholera than if the bacteria is ingested alone.
It explains that stomach acid kills most of the cholera bacteria as neutralizer of acid is taken with bacteria results in cholera. Correct answer is E.
