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 1811:00 AM PST
-12:00 PM PST
Join us in a live GMAT practice session and solve 30 challenging GMAT questions with other test takers in timed conditions, covering GMAT Quant, Data Sufficiency, Data Insights, Reading Comprehension, and Critical Reasoning questions.
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.
Updated on: 07 Sep 2019, 03:40
Originally posted by visheshsahni on 10 Aug 2018, 12:11.
Last edited by Sajjad1994 on 07 Sep 2019, 03:40, edited 4 times in total.
Last edited by Sajjad1994 on 07 Sep 2019, 03:40, edited 4 times in total.
Updated - Complete topic (452).
Kudos
Bookmarks
Question 1
B
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:
76% (03:03) correct
24%
(03:14) wrong
based on 197
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:
45%
(medium)
Question Stats:
58% (01:15) correct 42%
(01:21) wrong
based on 277
sessions
History
Date
Time
Result
Not Attempted Yet
Question 3
C
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
95%
(hard)
Question Stats:
18% (01:22) correct 82%
(01:06) wrong
based on 265
sessions
History
Date
Time
Result
Not Attempted Yet
Question 4
A
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
85%
(hard)
Question Stats:
33% (01:24) correct 67%
(01:36) wrong
based on 259
sessions
History
Date
Time
Result
Not Attempted Yet
Question 5
B
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:
38% (01:05) correct 63%
(00:59) wrong
based on 248
sessions
History
Date
Time
Result
Not Attempted Yet
Question 6
B
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
95%
(hard)
Question Stats:
18% (01:00) correct 82%
(00:50) wrong
based on 228
sessions
History
Date
Time
Result
Not Attempted Yet
New Project RC Butler 2019 - Practice 2 RC Passages Everyday
Passage # 143, Date : 13-APR-2019
This post is a part of New Project RC Butler 2019. Click here for Details
Passage # 143, Date : 13-APR-2019
This post is a part of New Project RC Butler 2019. Click here for Details
Shortness, reduced mobility and sore joints may not come to mind when you think of survival of the fittest. But human evolution could suggest otherwise. In a new study, researchers found that as early humans migrated into colder northern climates, a genetic mutation that knocks about a centimeter off height and increases the risk of osteoarthritis by up to 80 percent may have helped some of them survive the most recent ice age. While some traits resulting from this mutation may seem unfavorable today, they were advantageous to early humans venturing out of Africa about 60,000 years ago. “There are many cases like this where evolution is a trade-off,” said David Kingsley, an author of the study, which appeared in Nature Genetics on Monday, and a professor of developmental biology at Stanford University.
The shorter stature may have helped these prehistoric humans retain heat and stave off frostbite in their extremities, the authors said. It also may have reduced their risk of life-threatening bone fractures when slipping on icy surfaces. But the same gene puts humans at greater risk for arthritis in the modern era as they live well beyond their reproductive years. The study looked at variants of the GDF5 gene, which was first linked to skeletal growth in the early 1990s, and is known to be involved in bone growth and joint formation. The researchers wanted to understand how the DNA sequences around it might affect the gene’s expression, focusing on one region they named GROW1.
After analyzing the sequence of GROW1 in the 1000 Genomes Project database, a collection of sequences from human populations around the globe, the researchers identified a change in one nucleotide, the basic building block of DNA. The change is prevalent in Europeans and Asians but rare in Africans. To see if that mutation was incidental or actually caused shorter stature, they tested the nucleotide change in mice and found it decreased the length of their long bones, much as it is thought to do in humans. That mutation of the regulatory region analyzed in the study is present in more than 50 percent of the population in Europe and Asia. In some Asian populations, it’s up to 90 percent, Dr. Kingsley said. Even if the variant plays only a small role in increasing arthritis risk, the sheer number of people who possess it means it can have a significant effect. “The very abundance of the change means it could contribute to a lot of cases of arthritis,” Dr. Kingsley said.
A similar evolutionary paradox can be seen with sickle cell anemia, a condition in which a low number of red blood cells makes it difficult to carry adequate oxygen throughout the body, Dr. Kingsley said. A genetic variant causes a high rate of the disease in African populations. But that variant was favored because it also confers protection against malaria. “The genome is complex and our evolutionary history is complex,” said Terence D. Capellini, one of the lead authors on the study and an associate professor in the department of human evolutionary biology at Harvard University. “Because of that complexity, relationships emerge between different aspects of our biology that may seem paradoxical. As we reveal this history of our genome and how it affects our biology, we begin to understand the connections.”
As with many aspects of evolutionary research, it’s easier to figure out what traits were favored than it is to explain why. While shorter stature may have been a protection against the cold and icy terrain, it’s hard to be certain, said George Perry, associate professor of anthropology and biology at Pennsylvania State University, who is not affiliated with the study. “We’re not going to know that without some combination of a time machine and an experiment we can’t do,” he said. But detailed studies like this can help further our understanding of complex evolutionary processes and the potential consequences for modern medicine and human health, Dr. Perry said.
The shorter stature may have helped these prehistoric humans retain heat and stave off frostbite in their extremities, the authors said. It also may have reduced their risk of life-threatening bone fractures when slipping on icy surfaces. But the same gene puts humans at greater risk for arthritis in the modern era as they live well beyond their reproductive years. The study looked at variants of the GDF5 gene, which was first linked to skeletal growth in the early 1990s, and is known to be involved in bone growth and joint formation. The researchers wanted to understand how the DNA sequences around it might affect the gene’s expression, focusing on one region they named GROW1.
After analyzing the sequence of GROW1 in the 1000 Genomes Project database, a collection of sequences from human populations around the globe, the researchers identified a change in one nucleotide, the basic building block of DNA. The change is prevalent in Europeans and Asians but rare in Africans. To see if that mutation was incidental or actually caused shorter stature, they tested the nucleotide change in mice and found it decreased the length of their long bones, much as it is thought to do in humans. That mutation of the regulatory region analyzed in the study is present in more than 50 percent of the population in Europe and Asia. In some Asian populations, it’s up to 90 percent, Dr. Kingsley said. Even if the variant plays only a small role in increasing arthritis risk, the sheer number of people who possess it means it can have a significant effect. “The very abundance of the change means it could contribute to a lot of cases of arthritis,” Dr. Kingsley said.
A similar evolutionary paradox can be seen with sickle cell anemia, a condition in which a low number of red blood cells makes it difficult to carry adequate oxygen throughout the body, Dr. Kingsley said. A genetic variant causes a high rate of the disease in African populations. But that variant was favored because it also confers protection against malaria. “The genome is complex and our evolutionary history is complex,” said Terence D. Capellini, one of the lead authors on the study and an associate professor in the department of human evolutionary biology at Harvard University. “Because of that complexity, relationships emerge between different aspects of our biology that may seem paradoxical. As we reveal this history of our genome and how it affects our biology, we begin to understand the connections.”
As with many aspects of evolutionary research, it’s easier to figure out what traits were favored than it is to explain why. While shorter stature may have been a protection against the cold and icy terrain, it’s hard to be certain, said George Perry, associate professor of anthropology and biology at Pennsylvania State University, who is not affiliated with the study. “We’re not going to know that without some combination of a time machine and an experiment we can’t do,” he said. But detailed studies like this can help further our understanding of complex evolutionary processes and the potential consequences for modern medicine and human health, Dr. Perry said.
1. Which evolutionary paradox has the author touched upon in the passage?
A. The higher the number of red blood cells, the higher is the protection against malaria.
B. A genetic mutation that provided protection against the cold and fractures in the past now enhances the risk of osteoporosis and arthritis.
C. The very abundance of genomes contributes to increasing the risk of osteoarthritis.
D. Less oxygen throughout the body will lead to a decrease in immunity against malaria.
E. None of these
A. The higher the number of red blood cells, the higher is the protection against malaria.
B. A genetic mutation that provided protection against the cold and fractures in the past now enhances the risk of osteoporosis and arthritis.
C. The very abundance of genomes contributes to increasing the risk of osteoarthritis.
D. Less oxygen throughout the body will lead to a decrease in immunity against malaria.
E. None of these
2. Which of the following can possibly be one of the many cases where evolution is a trade-off?
A. Sacrificing a few hours of sleep so we can get up early in the morning and work on our fitness.
B. Prescription of hormone replacement therapy to post-menopausal women – while it may reduce the risk of ovarian cancer, it will reduce the risk of breast cancer.
C. While higher birth weight provides a higher chance of survival in the first few weeks after birth, babies that are too large have higher susceptibility to airborne infections.
D. Certain variants of a gene called APOL1 either make people resistant to trypanosomal infections or increase the risk of kidney failure.
E. None of these
A. Sacrificing a few hours of sleep so we can get up early in the morning and work on our fitness.
B. Prescription of hormone replacement therapy to post-menopausal women – while it may reduce the risk of ovarian cancer, it will reduce the risk of breast cancer.
C. While higher birth weight provides a higher chance of survival in the first few weeks after birth, babies that are too large have higher susceptibility to airborne infections.
D. Certain variants of a gene called APOL1 either make people resistant to trypanosomal infections or increase the risk of kidney failure.
E. None of these
3. Which of the following statements correctly highlights the impact of shorter stature on modern humans as can be inferred from the passage?
A. Shorter stature can protect humans against the risk of osteoporosis and arthritis.
B. Shorter stature can help in reducing the risk of life-threatening bone fractures.
C. Shorter stature can be a hindrance to fitness.
D. Can not be inferred.
E. Can be inferred but none of the options provided here.
A. Shorter stature can protect humans against the risk of osteoporosis and arthritis.
B. Shorter stature can help in reducing the risk of life-threatening bone fractures.
C. Shorter stature can be a hindrance to fitness.
D. Can not be inferred.
E. Can be inferred but none of the options provided here.
4. Which of the following statements is consistent with the information given in the passage
A. Generally, Europeans and Asians are shorter than Africans.
B. GROW1 is responsible for causing shorter stature.
C. The growth region GROW1 is endogenous to the GDF5 gene.
D. The mutation in the GDF5 gene is one of the main reasons as to why arthritis is prevalent among Asians and Europeans.
E. None of these
A. Generally, Europeans and Asians are shorter than Africans.
B. GROW1 is responsible for causing shorter stature.
C. The growth region GROW1 is endogenous to the GDF5 gene.
D. The mutation in the GDF5 gene is one of the main reasons as to why arthritis is prevalent among Asians and Europeans.
E. None of these
5. Which the following statements about the evolutionary studies mentioned in the passage is true?
A. There is a foolproof method to conclude the findings of the study in question.
B. The studies may help in shaping up modern health care.
C. Explaining why certain traits are favorable is more difficult than figuring out what those traits are.
D. The studies are full of paradoxes which make them more complex to understand.
E. None of these
A. There is a foolproof method to conclude the findings of the study in question.
B. The studies may help in shaping up modern health care.
C. Explaining why certain traits are favorable is more difficult than figuring out what those traits are.
D. The studies are full of paradoxes which make them more complex to understand.
E. None of these
6. Which of the following can be inferred from the passage?
A. People who have arthritis tend to survive extreme conditions better than those who don't.
B. At one point of time, all the humans on Earth belonged to Africa.
C. The genetic mutation that makes people shorter is the reason why early humans survived the most recent ice age.
D. The traits that our ancestors found to be advantageous are the same traits that we find to be disadvantageous.
E. None of these
A. People who have arthritis tend to survive extreme conditions better than those who don't.
B. At one point of time, all the humans on Earth belonged to Africa.
C. The genetic mutation that makes people shorter is the reason why early humans survived the most recent ice age.
D. The traits that our ancestors found to be advantageous are the same traits that we find to be disadvantageous.
E. None of these
Source: ISB India - GMAT Weekly
Difficulty Level: 700
Difficulty Level: 700
10 Aug 2018, 15:13
Kudos
Bookmarks
Explanation for Q6 ??
why B? and Why other choices eliminated ?
why B? and Why other choices eliminated ?
10 Aug 2018, 16:33
Kudos
Bookmarks
narayandutta
I will quote just 2 things and you will be satisfied without any other explanation.
In a new study, researchers found that as early humans migrated into colder northern climates, a genetic mutation that knocks about a centimeter off height and increases the risk of osteoarthritis by up to 80 percent may have helped some of them survive the most recent ice age.
they were advantageous to early humans venturing out of Africa about 60,000 years ago
From the highlighted, you can infer. Also, please have a look at the bold text - It clearly says some of them. Eliminates any chances for option D since D is more on generic and population as a whole kind of terms.
---------------------
+1 Kudos if this helps anyone.
