It is currently 26 Mar 2019, 16:48
My Tests

Close

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

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

The transplantation of organs from one individual to another

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Moderator
Moderator
User avatar
Joined: 18 Apr 2015
Posts: 5919
Followers: 96

Kudos [?]: 1159 [0], given: 5501

CAT Tests
The transplantation of organs from one individual to another [#permalink] New post 12 Feb 2019, 11:20
Expert's post
00:00

Question Stats:

0% (00:00) correct 100% (10:00) wrong based on 2 sessions
The transplantation of organs from one individual to another normally involves two major problems: (1) organ rejection is likely unless the transplantation antigens of both individuals are nearly identical, and (2) the introduction of any unmatched transplantation antigens induces the development by the recipient of donor-specific lymphocytes that will produce violent rejection of further transplantations from that donor. However, we have found that among many strains of rats these "normal" rules of transplantation are not obeyed by liver transplants. Not only are liver transplants never rejected, but they even induce a state of donor-specific unresponsiveness in which subsequent transplants of other organs, such as skin, from that donor, are accepted permanently. Our hypothesis is that (1) many strains of rats simply cannot mount a sufficiently vigorous destructive immune-response (using lymphocytes) to outstrip the liver's relatively great capacity to protect itself from immune-response damage and that (2) the systemic unresponsiveness observed is due to concentration of the recipient's donor-specific lymphocytes at the site of the liver transplant.
17. The primary purpose of the passage is to treat the accepted generalizations about organ transplantation in which of the following ways?

(A) Explicate their main features
(B) Suggest an alternative to them
(C) Examine their virtues and limitations
(D) Criticize the major evidence used to support them
(E) Present findings that qualify them

[Reveal] Spoiler: OA
E


18. It can be inferred from the passage that the author believes that an important difference among strains of rats is the

(A) size of their livers
(B) constitution of their skin
(C) strength of their immune-response reactions
(D) sensitivity of their antigens
(E) adaptability of their lymphocytes

[Reveal] Spoiler: OA
C


19. According to the hypothesis of the author, after a successful liver transplant, the reason that rats do not reject further transplants of other organs from the same donor is that the

(A) transplantation antigens of the donor and the recipient become matched
(B) lymphocytes of the recipient are weakened by the activity of the transplanted liver
(C) subsequently transplanted organ is able to repair the damage caused by the recipient's immune-response reaction
(D) transplanted liver continues to be the primary locus for the recipient's immune-response reaction
(E) recipient is unable to manufacture the lymphocytes necessary for the immune-response reaction

[Reveal] Spoiler: OA
D


20. Which of the following new findings about strains of rats that do not normally reject liver transplants, if true, would support the authors' hypothesis?

I. Stomach transplants are accepted by the recipients in all cases.

II. Increasing the strength of the recipient's immune-response reaction can induce liver-transplant rejection.

III. Organs from any other donor can be transplanted without rejection after liver transplantation.

IV. Preventing lymphocytes from being concentrated at the liver transplant produces acceptance of skin transplants.

(A) II only
(B) I and III only
(C) II and IV only
(D) I,II, and III only
(E) I, III, and IV only

[Reveal] Spoiler: OA
A


_________________

Get the 2 FREE GREPrepclub Tests

Intern
Intern
Joined: 21 Feb 2019
Posts: 1
Followers: 0

Kudos [?]: 0 [0], given: 0

Re: The transplantation of organs from one individual to another [#permalink] New post 23 Feb 2019, 00:41
Can someone explain why the 3rd reasoning is incorrect in the last question
Intern
Intern
Joined: 25 Jan 2019
Posts: 3
Followers: 0

Kudos [?]: 0 [0], given: 0

Bookmark this post [#permalink] New post 23 Feb 2019, 11:05
You have hit the mark. In it something is also idea good, agree with you.
Moderator
Moderator
User avatar
Joined: 18 Apr 2015
Posts: 5919
Followers: 96

Kudos [?]: 1159 [0], given: 5501

CAT Tests
Re: The transplantation of organs from one individual to another [#permalink] New post 23 Feb 2019, 11:29
Expert's post
Analyze one by one, then look at the options.

1) We do not know

Quote:
I. Stomach transplants are accepted by the recipients in all cases.

Always donor-specific


2) Correct item.

Quote:
1) many strains of rats simply can not mount a sufficiently vigorous destructive immune-response (using lymphocytes) to outstrip the liver's relatively great capacity to protect itself from immune-response damage


If it was the reverse: that the immune-response was vigorous, then B would be false.


3) Unknown. Can't judge whether it is repulsive. If you see any other donor (after all, you can call any other donor), you should realize that this option is too wavey and does not converge at all, so it is not optimistic.

I.E the transplant is always case-by-case. It is always donor-specific


4) In reverse, according to the second hypothesis in the later part of the article, if these lymphocytes are not collected in the liver and removed, they should start to protest after skin transplantation and begin to reject.

Quote:
(2) the systemic unresponsiveness observed is due to concentration of the recipient's donor-specific lymphocytes at the site of the liver transplant.

_________________

Get the 2 FREE GREPrepclub Tests

Re: The transplantation of organs from one individual to another   [#permalink] 23 Feb 2019, 11:29
Display posts from previous: Sort by

The transplantation of organs from one individual to another

  Question banks Downloads My Bookmarks Reviews Important topics  


cron

GRE Prep Club Forum Home| About| Terms and Conditions and Privacy Policy| GRE Prep Club Rules| Contact

Powered by phpBB © phpBB Group

Kindly note that the GRE® test is a registered trademark of the Educational Testing Service®, and this site has neither been reviewed nor endorsed by ETS®.