PT34.S3.Q19 - Light is registered in the retina

simple_jack

Alright, this was a confusing question but I'm still a little unsure about one part of it.

It's in the CC MSS section, so you guys can go look at it. Essentially the stimulus states that light is registered in the retina when [rhodopsin] molecules change shape. These molecules can change shape without the light simply by normal molecular motion, which introduces error into the visual system.

The final part is what trips me up. It says that the amount of molecular motion is directly proportional to the temperature of the retina.

OK, so this whole thing hinges on the definition of "directly proportional". What exactly does that mean? Well it means that as X increases, then so does Y and vice versa. OK got it. From this, I can assume that as temperature increases, so does the amount of movement. And as temperature decreases, then so does movement. I mean, that's what directly proportional means, increase X increase Y, etc...

My problem here is that the stimulus does not say whether more or less movement creates error. It simply says that "movement" in general creates error. But, like I said, this begs the question as to what type of movement creates the error? Does more movement create more error? Does less movement create less error? How am I supposed to infer this? I guess one could take the step in assuming that since less movement brings us closer to the state of no movement, then it must be that less movement causes less error. And since more movement is moving away from the state of no movement, more movement is thus causing more error. Since a state of no movement would essentially mean no error.

But this just seems to imply a lot of advanced deductions that one is expected to make while under the stress of trying to comprehend this information in the first place. I guess I pretty much answered my question in thinking this all through out loud, so let me know what you guys think as well.

Admin note: edited title
https://7sage.com/lsat_explanations/lsat-34-section-3-question-19/

Logic Gainz

But, like I said, this begs the question as to what type of movement creates the error?

I think the kind of movement that creates the error you're referring to is the kind that occurs without their being light to hit the molecule before the movement happens. If a temperature increase causes more non-light movement to occur, we would then have the case where more movement is occurring without their being light to provoke it, thereby increasing the instance of error.

You might be wondering why I'm deeming movement without light an error at all, but I'd argue that it is stated for us in the stimulus by the statement, "...rhodopsin molecules sometimes change shape because of normal molecular motion, thereby introducing error into the visual system."

Chardiggity

My take:

But, like I said, this begs the question as to what type of movement creates the error?

Normal molecular motion.

Does more movement create more error? Does less movement create less error?

"Molecules sometimes (emphasis mine) change shape because of normal molecular motion."
So normal molecular motion introduces the possibility of changing shape in absence of light (i.e. registering light in error).

To me, it doesn't say more or less movement causes more or less error, it's that more potential cause (of error) means more potential result (for error). The correct answer choice refers to the visual systems of these animals being more "error-prone", or having a greater potential for error.

Hope this is helpful (and hopefully not way off base)!

nye8870

if molecular motion increases with temp ...and an animals body temp is relative to temp of environment, then a hot environment will make body temp rise hence more molecular motion