PT122.S1.Q10 > Question

SECTION 1 · lr

Question 1 Question 2 Question 3 Question 4 Question 5 Question 6 Question 7 Question 8 Question 9 Question 10 Question 11 Question 12 Question 13 Question 14 Question 15 Question 16 Question 17 Question 18 Question 19 Question 20 Question 21 Question 22 Question 23 Question 24 Question 25

SECTION 2 · lr

SECTION 3 · rc

PASSAGE 1

Question 1 Question 2 Question 3 Question 4 Question 5 Question 6

PASSAGE 2

Question 7 Question 8 Question 9 Question 10 Question 11 Question 12 Question 13

PASSAGE 3

Question 14 Question 15 Question 16 Question 17 Question 18 Question 19 Question 20

PASSAGE 4

Question 21 Question 22 Question 23 Question 24 Question 25 Question 26 Question 27

SECTION 4 · lr

The author concludes that flies of a certain species flies lacking ultraviolet vision must have some damage to a particular gene. His reasoning is that flies who don’t have this gene lack ultraviolet vision.

The author’s conclusion is about all flies of a certain species who lack ultraviolet vision. But we don’t know that all flies who lack UV vision lack this particular gene. We only know that flies who lack this gene also lack UV vision. What if other flies lack UV vision because of exposure to certain light or ocular injuries? There would then be causes of fly UV blindness that weren’t related to this gene.

Consequently, the author must assume that there are no potential causes of UV blindness in flies of this species except a problem with this particular gene.

This assumption is too strong to be necessary. Some understanding of the relationship may be necessary for the argument. But it doesn’t have to be an especially strong understanding.

Negated, this is: there is another gene required for the formation of the UV vision cells. If so, a problem with that gene, instead of the gene the author refers to, could lead to UV blindness in some cases. That would contradict the author’s argument, so he must assume (B) is true.

Note that this is a subset of the broader necessary assumption that there are no other potential causes of UV blindness in this species of fly.

The scientist is only considering one species of fly, so the traits of other species are irrelevant.

This is too strong to be necessary for the argument. Negated, this is: the gene change had an effect on the flies other than the lack of UV vision cells. That effect wouldn’t have to be relevant to UV vision, so this doesn’t contradict the author’s argument.

Since the author’s goal is conclude that UV blindness has a genetic cause, he would definitely not need to assume that it has environmental influences.

PrepTest 122 - Section 1 - Question 10

Difficulty

Analysis

Answer Popularity

Question history

Confirm action