<p>You guys are making me nervous. I haven’t even finished campbells once lol.</p>
<p>^I haven’t either, but I still made semis haha</p>
<p>hm, well I like taking notes because once i finish them, I’ve basically condensed the info that I need to know into one pile so I don’t need to use the huge book anymore</p>
<p>Does anyone know how to review the knowledge for this sort of questions?
8(2012 semifinal). All amino acids except lysine and leucine can be broken down into precursors for gluconeogenesis. What are the products produced by the breakdown of lysine and leucine that prevent them from functioning in that pathway?
A. Oxaloacetate and acetyl-CoA
B. Pyruvate and succinate
C. Acetyl-CoA and acetoacetate
D. Succinyl-CoA and acetoacetate
E. Acetaldehyde and pyruvate</p>
<p>There are two types of amino acids: glucogenic and ketogenic. Glucogenic ones are broken down into pyruvate and can be used in gluconeogenesis, so we can assume that these two amino acids are ketogenic. Ketogenic ones are broken down into acetyl-CoA and products used in the formation of ketone bodies, so because acetoacetate can be assumed to be an intermediate (acetyl CoA–>acetoacetate–>ketone body), the answer has to be C. Plus, if you know oxaloacetate isn’t a product of the breakdown of ketogenic amino acids, that works too :p</p>
<p>Is this the first year the cutoff has been this high?? It’s been around 24-25 before. I suspect its because of the extension CEE gave and the people on here who posted questions w/o informing about the extension!!! 
</p>
<p>One year it was 29…</p>
<p>@zinwell - If you see a question like this and aren’t really familiar with ketogenic amino acid metabolism, you can try solving it by extrapolating from facts you know (nowhere near as accurate as just knowing it like @botherme, but good in a pinch). </p>
<p>1) We’re trying to NOT synthesis glucose, so we probably want to avoid anything found in glycolysis (eliminating B and E, which contain pyruvate).
2) In the Open Exam, we saw that fatty acids cannot be converted to glucose (called glyoxylation, I think), and from Campbell we know that fatty acids enter metabolism at the Acetyl-CoA level via beta-oxidation. This suggests that Acetyl CoA cannot be converted to glucose. This leaves us with A and C
3) Here, you can just guess (C is statistically more likely than A :P). I don’t think you can reasonably narrow down between the two without additional knowledge. Anything from @botherme’s post above would work. </p>
<p>@botherme - Acetoacetate is a ketone body, not just an intermediate to ketone bodies (<a href=“Ketone bodies - Wikipedia”>http://en.wikipedia.org/wiki/Ketone_bodies</a>). </p>
<p>oops
Points is points, though XD</p>
<p>this bean is bio knowledgeably totipotent </p>
<p>Hey guys my school didn’t submit the payment yet so our registration isn’t approved yet. Did CEE send those of you who are semifinalists emails that notified you of anything? I wont be able to login to the portal for a while so just wondering…</p>
<p>hey bean, are you a junior or a senior?</p>
<p>@botherme - Junior. You?</p>
<p>Just a general note to everyone - some schools are indeed being given extensions for the semifinal exam, so let’s avoid discussing questions publicly for at least 14 days after the exam’s official range ends (ideally even longer, but at least a couple of weeks to ensure that no one has an unfair advantage on semis). </p>
<p>Soph</p>
<p>Sorry accidentally repeated below</p>
<p>Wow 41 is an incredible score for a sophomore (or anyone else, for that matter) - that’s where most of last year’s campers scored. </p>
<p>On a similar note - does anyone have the histogram of scores (I know there was one last year)? Thanks</p>
<p>try emailing cee</p>
<p><a href=“Untitled document - Google Docs”>https://docs.google.com/document/d/1Jlo7qyaaaj2aBSL7uEI_l7dasqnl874J6tflKOSvVXU/edit</a>
And thanks, bean, but I know you made camp last year as a soph too :)</p>
<p>oops sorry guys, I forgot to make it public
<a href=“Untitled document - Google Docs”>Untitled document - Google Docs;
<p>Dang this year had a lot of high scorers, that’s good news</p>