#10 - People who are allergic to cats are actually allergic

[bekam]

Hi there, I read through the explanations but it's still not clicking.

We know that the people are allergic to proteins. However, we don't know which proteins are responsible because it varies from person to person. We also know that "it is common for a given cat to cause an allergic reaction in some - but not all - allergy sufferers." In other words, a cat could have proteins X and Y; one person would be allergic to X, while another one would be allergic to Y.

How is (C) supported then? I mean, the cats could be identical with respect to their protein, and certain groups of people would be allergic to protein X, while others would be allergic to Y. Previous posts by the Admin and Steve Stein generally state the same explanation: "The author provides that cats can commonly elicit allergic reactions in some allergy sufferers and not others. Combined with the fact that these allergies are caused by specific proteins in the skin and saliva, this supports the inference that these proteins must vary among cats." But I can't see how we are making that inference. Couldn't the proteins in all cats remain the same yet affect people differently based on which protein they are susceptible to?

Nekrowizard had a similar question to mine. In a part of his explanation, Jon Gore states, "If all cats secrete the same proteins, then every cat would cause an allergic reaction in all people who are allergic to cats." But that doesn't seem right because it depends on which proteins the different groups of people are susceptible to, in accordance with the stimulus.

Please help before I throw the laptop out of the window. Thanks in advance.

[Poonam Agrawal]

Hi bekam,

This is where you've gone wrong in your interpretation of the stimulus:

In other words, a cat could have proteins X and Y; one person would be allergic to X, while another one would be allergic to Y.

The reason why this is wrong is because it is not equivalent to what we are given in the stimulus. We are told that: it is common for a cat to cause an allergic reaction in some, but not all, people. In your interpretation above, both people (all people) would be allergic to the cat because the cat carries the proteins that each person is allergic to.

We have to amend your statement to say, "in other words, one cat could have proteins X and Z. Another cat could have proteins Y and Z. One person is allergic to protein X, and the other person is allergic to protein Y." This is the only way to make the statement in the stimulus true, that a cat can cause an allergic reaction in some, but not all, people.

This supports answer choice (C), which says that not all cats have the same proteins. Let me know if that helps to clarify!

[AnaSol]

Hi,

I am with Bekam on this one. I have read all the explanations, as well as the answer given to Bekam and I don't get it. Why is the onus on the cat and not on the recipient aka allergy sufferer?

Why is C better than B?

Thanks,

[Chandler H]

Hi,

I am with Bekam on this one. I have read all the explanations, as well as the answer given to Bekam and I don't get it. Why is the onus on the cat and not on the recipient aka allergy sufferer?

Why is C better than B?

Thanks,

Hi Ana and Bekam,

OK, let's say that all cats are identical with respect to the proteins—that is, we are constructing the scenario in which answer choice (C) is false.

In this scenario, all cats have proteins X, Y, and Z. Some people are allergic to X, others are allergic to Y, and still others are allergic to Z. (Or some combination of the three—some people are allergic to X and Y, some people to Y and Z, et cetera).

Within these rules, try to construct a scenario in which some people are allergic to some cats but not others.

You can't, right? Because every cat has every allergen protein. If you're allergic to a different protein, other than X, Y, and Z, then you're just not allergic to cats.

Therefore, answer choice (C) has to be true. Does this make sense?