USABO 2017-2018

I still haven’t received my scores yet and it’s around 9:26pm in my area. Do you know if some scores are delayed? Because I know a few people who did get their scores already and also some who didn’t.

One question regarding to the finalist qualification. There is a mom told me the top 20 finalist score is semifinal exam score plus open exam score. Is that true?

No it’s not.

Thanks! That is what I thought originally!

Score: 22
Status: Semifinalist

Let’s go!!! I’m pretty sure I barely made the cutoff, but time to cram for the semifinal exam!

Does anyone have good websites/online pdfs regarding amino acids? Campbell’s discussion of them seems insufficient…

Here’s a good reference: http://leah4sci.com/wp-content/uploads/2015/05/amino-acid-chart-mcat-cheat-sheet-study-guide1.jpg

Pretty much everything you may need to know is on that, but you do need some basic chemistry intuition. Also know methionine is the start codon, cysteine has disulfide bridges, and glycine and proline are missing from alpha helices and you should be fine.

if i’m starting the USABO club at my school should I start recruiting members now for next year’s exam or wait until next school year?

@avgsopho1223 Start recruiting now cuz in my school the club started last year and I know a kid who was in the same situation as you and he decided to recruit then and it helped out a lot.

I saw one of the questions on the semifinals exam for 2012, and it asked which amino acid shuttles H+.
Are you sure that
http://leah4sci.com/wp-content/uploads/2015/05/amino-acid-chart-mcat-cheat-sheet-study-guide1.jpg
is sufficient enough?

@iamaccuser1 Here’s the question you were talking about:

  1. Which of the following amino acids has an R-group that can “shuttle” hydrogen ions? A. Alanine B. Leucine C. Valine D. Histidine E. Isoleucine

This is a chemistry question. In order for an R-group to “shuttle” hydrogen ions, it would need a functional group capable of binding to them, or in other words, one that is basic. The only basic amino acid on this list is histidine, and D is the correct answer. However, in order to figure that out, you’d either need to know which amino acids are polar/nonpolar/acidic/basic or know the structures of their R-groups. Either of these can be found on the handout.

Does anyone know if the semifinal exam will have multiple true/false questions where a question can have several correct answers? One the USABO website, “about the exams” says it will, but “what’s new in 2018” says this is only for finals and IBO. Any ideas?

I’m pretty sure there are questions like that…In the answer keys to the Semis exams, I saw questions with multiple correct answers. I think such questions are of Part B, where Paty A is one correct answer and Part C is open-ended.

Well I know they have in the past, but part of the website made it seem like they might have changed that

When can we begin discussion?

I would think that discussion of questions can begin now, considering that the deadline for testing was yesterday. But I would wait a week more just in case.

Ok. Well I’m not going to give any details away regarding the test but I do think I completely bombed this one. What will camp cutoff be? (Also why was camp moved back to end of June?)

@glutathione it might be because of the new host college. Camp used to be hosted by Purdue, but now it’s hosted by UC San Diego (I think those are the right colleges), so scheduling might have had to be different.

@veggieburrito check out the amino acid table here https://biolympiads.com/amino-acid-properties/. Includes descriptions and key properties.

Oh, apparently extensions were granted so we should refrain from discussion until maybe next weekend.