ShmoopTube

00:03

Here's an unshmoopy question you may find on the ACT Science exam...

00:09

Time to pause and review.

00:10

No, not your sister's diary. This passage, s'il vous plait.

00:23

Which of the following pieces of evidence strongly supports the idea that plant patterning

00:27

is caused by mechanical stress?

00:30

And here are the potential answers...

00:37

This problem is asking us to find some solid evidence to support the idea of mechanical

00:42

stress causing patterning.

00:44

Well, we could read the passage yet again...or, we can use our awesome deducing skills to

00:48

figure out the answer by just looking at the choices.

00:52

So how do we deduce the answer?

00:54

Well, we're looking for evidence. Evidence means that it's something that we have observed.

00:59

Option A is true, but it doesn't provide us with how we have

01:02

observed it, or how it affects patterning.

01:04

Same with Option C. We know that auxin causes plants to grow,

01:07

but it doesn't provide evidence of mechanical stress causing patterning.

01:11

Option B. Those adorable patterns on raccoons do not have anything to do with PLANT pattering.

01:17

That leaves us with D.

01:18

"Scientists can injure a plant, and the plant patterning responds to this action

01:22

by taking on a pattern dependent on the size of the injury."

01:27

Sounds like pretty solid evidence to us.

01:29

Thorough, and it explains the effect of observation on patterning.

01:34

So D is the best answer.

Full Transcript