The Official June 2015 MCAT Thread

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Doesn't this depend on its size i.e. how many Ac-CoA's you can chop out (along with maybe a propionyl CoA)? So without context it's hard to know exactly "how many times more" energy this has got than a glucose molecule. We can definitely say it's more, though!

Of course, I meant it in that context. You would not be able to know how much more energy a FA has without knowing which one it is. But even then, I feel it's a stretch as it's pretty specific and this process can be situational. Such as the FA size, is it a sat or a unsat FA, uneven # FA? All of this makes this topic really difficult. This type of information would likely be in supported by a passage. If (and I doubt it) it were an FSQ, I would imagine the choices being in the realms of not even having to calculate, as only one answer would be a clear winner (I.e: 2ATP, 32ATP, 57 ATP, 128ATP; assuming a large enough FA)


In total agreement on this. The calculation of ATP based on the NADH and FADH2 standards you used (2.5 and 1.5, respectively) may be a stretch though, considering some use 1 for FADH2 and 2/3 for NADH. I think they'd either need to explicitly define it (where you have to know how many of those molecules are produced to get it) OR they'd have to have an answer that is close the answer you would get using either of the values for those molecules, with the other answers being too far away to matter. Either way I'm using 1.5/2.5. Seems to be the safest bet.

I agree. Same as the discrepancy for the amount of ATP produced in the TCA cycle. Based on the way AAMC practice has been, a lot of this information appears in passages and you're able to make these conclusions. They would likely say assume it produces X and Y amt of ATP.

And as we can see everyone, don't get tied up in specifics. BCH is full of debate and uncertainty. The human body is complex and were only beginning to truly understand it. The MCAT is not testing specifics. It's testing your ability to reach conclusions based on data and trends.
 
Isn't centripetal acceleration towards the middle of the circle, so centripetal force is inwards? I feel like your tension and Fc should be reversed, but I could be completely off 🙂

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Found this on google
 
I agree. Same as the discrepancy for the amount of ATP produced in the TCA cycle.

I thought the TCA cycle technically produces 0ATP. Have seen some diagrams that call the GTP an ATP, though. Can you clarify what you mean here? If you mean the amount of ATP eventually produced by the ETC, that actually was the context I was thinking of (unless I missed some other super key metabolic process where NADH/FADH2 are being produced, other than Glyceraldehyde-3-P dehydrogenase rxn in glycolysis or beta-ox which are sort of minor asides compared to TCA).

Then again, with the amount of rounds in beta-ox, maybe it isn't so minor. Can actually produce way more than the TCA cycle depending on size.
 
I thought the TCA cycle technically produces 0ATP. Have seen some diagrams that call the GTP an ATP, though. Can you clarify what you mean here? If you mean the amount of ATP eventually produced by the ETC, that actually was the context I was thinking of (unless I missed some other super key metabolic process where NADH/FADH2 are being produced, other than Glyceraldehyde-3-P dehydrogenase rxn in glycolysis or beta-ox which are sort of minor asides compared to TCA).

Then again, with the amount of rounds in beta-ox, maybe it isn't so minor. Can actually produce way more than the TCA cycle depending on size.

You are correct. Poor wording on my part. TCA indirectly produces ATP via the NADH/FADH2. . The ETC is what produces ATP, along with the 4 (net +2) in glycolysis.

Edit: Looked over my BCH notes/exams and they do actually state that TCA>>>0ATP and the BCH exam even had a trick Q over this. Thanks for making me think twice about it.
 
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Thought this might be helpful for people. With enzyme kinetics I need graphs to make sense of stuff. If you can't see the labels, Panel B = competitive, Panel C=non-competitive, and Panel D = uncompetitive.
I was freaking out about that and just watched an hour of videos derriving the m-m equation. makes way more sense now.
 
You are correct. Poor wording on my part. TCA indirectly produces ATP via the NADH/FADH2. My BCH class always worded it as TCA cycle produces ATP, but it was assuming you knew it was due to the FADH2/NADH. The ETC is what produces ATP, along with the 4 (net +2) in glycolysis.

Plus a GTP from TCA also right? Does that go in the overall count?
 
Plus a GTP from TCA also right? Does that go in the overall count?
IIRC, that one of the debatable/situational ones. Just like the actual values for NADH/FADH2. But knowing exactly what that GTP does is probably of low importance for this exam, in the grand scheme of things.
 
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For amino acids:
HAL is a positive guy! His, Arg, Lys
the neGAtively charged amino acids are Glu & Asp
Gee, CATS are "bi"polar! Gln, Cys, Asn, Thr, Ser
 
anyone going to void this one? sadly i missed the date to change and am probably going to void (basically screwed up and should've taken FL's a month in advance)
 
A lot of people take FLs less than a month before the exam though.
true but i guess it depends on the person. I've found that my score is increasing a lot after getting familiar with the questioning, and I need to do well because my gpa is not so great.. so i think the 3 weeks extra will help a lot for me.
 
true but i guess it depends on the person. I've found that my score is increasing a lot after getting familiar with the questioning, and I need to do well because my gpa is not so great.. so i think the 3 weeks extra will help a lot for me.

Increasing on what? There's one FL that's reliable. Unless you're planning to wait until fall. If you did >70% on it, that's a green light in my book. I don't know your goals though - you might need top 20, in which case take allllllll the time you need.
 
Increasing on what? There's one FL that's reliable. Unless you're planning to wait until fall. If you did >70% on it, that's a green light in my book. I don't know your goals though - you might need top 20, in which case take allllllll the time you need.
In addition to TPR, I heard EK is pretty good and that's what I've been doing and getting a higher score each time. I did the aamc FL in between EK and TPR and my scores have gotten a lot better. And I plan on doing the some TBR FL's as well. No not till fall, just till july. I don't need top 20 just any school 🙂. like I said, my gpa is the one that's holding me back so I need to do a lot better 😕
 
Just finished my AAMC FL

CP 54
CARS 70
Bio 46
PS 73

My MCAT is this Saturday. I guess I'm going to stay up and review what I did wrong.

CP: I actually got a lot of topics I wasn't good at and felt like I was worried more for time then trying to understand the passage.

CARS: I will be satisfied with this score considering I suck at verbal.

Bio: I felt like I rushed through this topic. I guess I will slow down more and try to understand the topic better.

PS: I can get much higher on this section. I'm the least worried about this section. I feel like I can do well on this.


I actually took the MCAT in May but voided due to computer problems. I feel like the one I took on May was much easier (maybe because I got topics I was good at), but I felt like the practice test was much harder than the real MCAT I took on May. Did anybody feel that way? :shrug:

Maybe tomorrow I will take the Official Guide test when I get off work. I know it's not the best thing to do night before the exam but I need to get my confidence up. Having to work and volunteer is taking a toll on me.
 
Increasing on what? There's one FL that's reliable. Unless you're planning to wait until fall. If you did >70% on it, that's a green light in my book. I don't know your goals though - you might need top 20, in which case take allllllll the time you need.

I agree.

In addition to TPR, I heard EK is pretty good and that's what I've been doing and getting a higher score each time. I did the aamc FL in between EK and TPR and my scores have gotten a lot better. And I plan on doing the some TBR FL's as well. No not till fall, just till july. I don't need top 20 just any school 🙂. like I said, my gpa is the one that's holding me back so I need to do a lot better 😕

TPR is good? I dont think anyone on this thread has said that, unless you're one of those studmuffins that are ripping those apart (protip: it's rare). You should be basing it off your AAMC and Official guide scores. To a lesser extent, the Q packs, KA, and then any test prep co (due to how far off so many of them were.)
Unless I absolutely knew I bombed the exam, I would never void. Even with being in the same situation as you. Stop doubting yourself and letting the mind game get to you. If you feel that voiding and retaking is going to be more reflective of who you are, then that's up to you. However, I would never go into the exam with that mindset. It's a toxic behavior to have.
 
Anyone know why tyrosine is aromatic? I thought aromatic compounds have 4n +2 pi electrons (2, 6, 10, etc) and tyrosine has 8 pi electrons unless I'm counting wrong.
 
Anyone know why tyrosine is aromatic? I thought aromatic compounds have 4n +2 pi electrons (2, 6, 10, etc) and tyrosine has 8 pi electrons unless I'm counting wrong.

Tyrosine has a phenyl ring, which is aromatic. Any molecule with one aromatic part is considered an aromatic molecule overall.
 
is it safe to assume that i'm not the only Saturday tester feverishly refreshing this thread every 5 minutes?

I'm taking it tomorrow. Idk about refreshing every 5 minutes, though, haha. You hoping to get the scoop on the difficulty of the passages? Think our test will be similar?
 
Got a call saying to arrive at 7AM, but no later than 7:30. Was the last one to arrive at 7:35. Thug lyfe.

I mean.. We're the ones paying $200 to take a 7 hour test. How are you gonna make us sit there for an extra hour?? WTF?? That makes the test day an 8 hour ordeal. Nah, bruh. I'll be there at 7:30, if they're lucky.
 
Do you have any advice for us before we try to slay this beast??

You really just have to go in there with confidence. I think that is what really helped me. I didn't let anyone trying to cram anything in last minute or talking through things with anyone in the testing center get to me. I knew what I knew and didn't let anyone else's interpretation sway mine.

Also, THINK critically! That can not be stressed enough. It has been mentioned countless times that this new test can be figured out if you just think about the questions and what they are asking.
Nothing I will say will be new to you all, but just go in and "try to have fun with it". This is probably the biggest test of your life up until this point! Hype on what this test means for you! It is going to help determine where your medical career will start. While that can be stressful of course, it should still be exciting!

Good luck to all! Willing to take any other questions if anyone has them. Just PM me.
 
I mean.. We're the ones paying $200 to take a 7 hour test. How are you gonna make us sit there for an extra hour?? WTF?? That makes the test day an 8 hour ordeal. Nah, bruh. I'll be there at 7:30, if they're lucky.

My test center told me to get there at 6:30 when I took it in May. Glad I got there around then, because it was packed! So it may be a good idea if you are testing in a big city to heed their suggestions.
 
Getting there early won't necessarily make your day longer. As soon as you get checked in, you can start. My testing center started checking us in around 7:15-7:30, so the first people in got done earlier than other people.
 
Lol the only thing I care about is if the test takers had any computer issues. I'm hoping the transitions between questions is as smooth as it was on the practice test. That's the only thing freaking me out.
 
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