Sentence Correction

SOURCE: PrincetonReview

Examination of reptile hearts shows that their structure differs from any mammal heart in being, unlike mammal hearts, divided into chambers by only a partial septum.

A. differs from any mammal heart in being
B. differs from that of any mammal heart, being
C. is different than any mammal heart; they are
D. is different than any mammal heart's, being
E. is different from that of any mammal heart; they are

OA: E

PrincetonReview's explanation: "Yes. This choice has the correct idiom."

MY QUESTION: Is this sentence really parallel? Don't you need to also make sure the things you're comparing are parallel? Shouldn't the sentence be "Examination of reptile hearts shows that their structure is different from that of mammal heartS..."?

we are talking about "structure" over here therefore, that of any mammal heart is ok because "that" is refering to "structure"............

yes E is correct. uses correct idiom different from, and uses correct comparison. "that" refers to the "structure"

Hey guys, I wasn't talking about the parallel construction with regards to the "structure". I was talking about the parallel construction with the "hearts".

I don't have a problem with "that" and its comparison with "structure".

What I am wondering is whether the sentence should have the following construction:

"reptile hearts... structure..." and "...that... mammal hearts..."

Answer E has...

"reptile hearts... structure..." and "...that... any mammal heart..."

Does this make sense?

I may be wrong, but please do advise. I dont like the structure of all the answer choice.
non-underlined part contains "unlike mammal hearts". UNLIKE like LIKE compares noun or noun phrases but no verb. All the choices are not using "UNLIKE" correctly.
E, "they are", "unlike mammal hearts" is incorrect. Correct form should "They, unlike mammal hearts, are XXXX".

Please suggest.

Nice observation singh181.
Watching this topic for experts comments.

singh181 wrote:I may be wrong, but please do advise. I dont like the structure of all the answer choice.
non-underlined part contains "unlike mammal hearts". UNLIKE like LIKE compares noun or noun phrases but no verb. All the choices are not using "UNLIKE" correctly.
E, "they are", "unlike mammal hearts" is incorrect. Correct form should "They, unlike mammal hearts, are XXXX".

Please suggest.

unlike mammal hearts is appositive phrase that can modify the modify the entire sentence before it. What i am trying to convey could be a bit vague

giovanni.gastone wrote:SOURCE: PrincetonReview

Examination of reptile hearts shows that their structure differs from any mammal heart in being, unlike mammal hearts, divided into chambers by only a partial septum.

A. differs from any mammal heart in being
B. differs from that of any mammal heart, being
C. is different than any mammal heart; they are
D. is different than any mammal heart's, being
E. is different from that of any mammal heart; they are

OA: E

PrincetonReview's explanation: "Yes. This choice has the correct idiom."

I received a PM asking me to comment.

In C and D, different than is not idiomatic. The correct idioms are X differs from Y or X is different from Y. Eliminate C and D.

Answer A incorrectly compares structure to any mammal heart. Eliminate A.

Similar error in B: structure...being unlike mammal hearts incorrectly compares structure to mammal hearts.

The correct answer is E.

To respond to some concerns raised above:

To compare the structure of reptile hearts to that of mammal hearts would not be incorrect, but such phrasing would change the meaning: it would imply that all mammal hearts have the same exact structure.

In E, it could be argued that the prepositional phrase unlike mammal hearts is functioning as an adverb, justifying its placement next to the verb are. Regardless, it's clear that the pronoun they (which refers to reptile hearts) is being compared to the noun mammal hearts. Whereas the other answer choices have very clear errors that cannot be debated, no such error exists in E.

GMATGuruNY wrote:

giovanni.gastone wrote:SOURCE: PrincetonReview

Examination of reptile hearts shows that their structure differs from any mammal heart in being, unlike mammal hearts, divided into chambers by only a partial septum.

A. differs from any mammal heart in being
B. differs from that of any mammal heart, being
C. is different than any mammal heart; they are
D. is different than any mammal heart's, being
E. is different from that of any mammal heart; they are

OA: E

PrincetonReview's explanation: "Yes. This choice has the correct idiom."

I received a PM asking me to comment.

In C and D, different than is not idiomatic. The correct idioms are X differs from Y or X is different from Y. Eliminate C and D.

Answer A incorrectly compares structure to any mammal heart. Eliminate A.

Similar error in B: structure...being unlike mammal hearts incorrectly compares structure to mammal hearts.

The correct answer is E.

To respond to some concerns raised above:

To compare the structure of reptile hearts to that of mammal hearts would not be incorrect, but such phrasing would change the meaning: it would imply that all mammal hearts have the same exact structure.

In E, it could be argued that the prepositional phrase unlike mammal hearts is functioning as an adverb, justifying its placement next to the verb are. Regardless, it's clear that the pronoun they (which refers to reptile hearts) is being compared to the noun mammal hearts. Whereas the other answer choices have very clear errors that cannot be debated, no such error exists in E.

Nice help Guruny, keep doing this, we need you on our path.