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For #32 on the AAMC FL (CPS section):

The Ka (affinity constant) is NOT the Km used in the Michaelis Mentin equation?

If it is, that means both warfarin and ibuprofen increase the apparent affinity of CPFX to BSA.

An increase in apparent affinity means that they are competitive inhibitors, meaning that CPFX binds to BSA at BOTH sites....am I on the right track here?!
 
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drrao88 said:
For #32 on the AAMC FL (CPS section):

The Ka (affinity constant) is NOT the Km used in the Michaelis Mentin equation?

If it is, that means both warfarin and ibuprofen increase the apparent affinity of CPFX to BSA.

An increase in apparent affinity means that they are competitive inhibitors, meaning that CPFX binds to BSA at BOTH sites....am I on the right track here?!
Click to expand...

They bind at both sites, but primarily at site II because the Ka/Ko for warfarin is much lower.

Ka represents the association constant while Ko represents the same thing except with no inhibitors are present (no warfarin or ibuprofen). The fact that both the Ka/Ko values are below 1 indicates that Ko is larger than Ka meaning that they are both inhibitors since the presence of warfarin/ibuprofen DECREASED Ka. So, you are correct about that.

Because the Ka/Ko for warfarin is lower than the Ka/Ko for ibuprofen, it means that the Ka for warfarin is lower since the two Ko values are comparable. The lower the Ka, the higher the affinity. So, CPFX has a much greater affinity for Site II over Site I.

I really hope I answered what you were asking and that I made sense 🙂
 
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finally took my first practice exam (AAMC FL) and got pretty good results, hovering around 88-92% in each section. Overall it felt easy, but some of the questions were so damn misleading. Especially in CARS. I'd say in order of increasing misleadingness: PS<BS<Psych<CARS. On many questions it seems that there are two options for which equally strong arguments could be made. Pretty annoying
 
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Caffein3 said:
I dont mind the psych! It can get a little tricky though with some of the extremely similar terms!

And I retook the AAMC FL today too. Only missed 1 in each section...Definitely remembered some answers, but its definitely good and it felt awesome to go through it again. I'm realizing how simple all of the questions are...it just comes down to if you can apply the basic knowledge we all know.
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That's really impressive even for a retake. When did you take it the first time?
 
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drrao88 said:
Lol 88-92% in each section, and it was your first exam when the real thing is in 2-3 days?

Cool.
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Yea I only gave myself like 3 weeks to study so I just finished content review yesterday. Definitely stressed me out a ton, but I need a huge amount of stress to study efficiently, that's how I've always been.

stressingout said:
They bind at both sites, but primarily at site II because the Ka/Ko for warfarin is much lower.

Ka represents the association constant while Ko represents the same thing except with no inhibitors are present (no warfarin or ibuprofen). The fact that both the Ka/Ko values are below 1 indicates that Ko is larger than Ka meaning that they are both inhibitors since the presence of warfarin/ibuprofen DECREASED Ka. So, you are correct about that.

Because the Ka/Ko for warfarin is lower than the Ka/Ko for ibuprofen, it means that the Ka for warfarin is lower since the two Ko values are comparable. The lower the Ka, the higher the affinity. So, CPFX has a much greater affinity for Site II over Site I.

I really hope I answered what you were asking and that I made sense 🙂
Click to expand...

The affinity constant is not the same thing as the Michaelis Menten constant https://en.wikibooks.org/wiki/Struc...ction/Heme_group/Hemoglobin/Affinity_Constant

The Lower the Ka, the LOWER the affinity. Warfarin basically just doesn't bind to site 1 on BSA to the same extent that Ibuprofen binds to site 2. Thus, there is less COMPETITION for CPFX to bind to site 1. Note that this logic assumes Ko is the same for site 1 and site 2, which you can verify by noticing that .755≈1.43/2x.
 
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700003 said:
Wow really nice! Do you have a strong science background? Or are you a researcher? lol
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Thanks! I have taken a lot of science classes, and I spend a lot of time reading papers because I'm very active as an undergrad researcher.

libertyyne said:
what did you use to study for physics/chem?
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Kaplan books, but I don't feel like they helped me that much. I'm a science tutor for fresh/soph level classes and that definitely helped me more.
 
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jd989898 said:
Thanks! I have taken a lot of science classes, and I spend a lot of time reading papers because I'm very active as an undergrad researcher.



Kaplan books, but I don't feel like they helped me that much. I'm a science tutor for fresh/soph level classes and that definitely helped me more.
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I am sure you will do fine. I am guesstimating that is a 516-518 with a 4 point margin of error each way.
 
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jd989898 said:
I appreciate that. Trust me, I need a score in that range. I'm applying MDPhD with a low-ish gpa. Been having nightmares about this lol. Only get one shot, can't mess it up.
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How low is your GPA? I'm sure you will be fine! Your MCAT to me looks like it has a good chance of being in the 520s =)
 
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What has everyone been using to study the psych research methods? There seems to be lots of questions that come up asking why a particular study is not valid (e.g. poor selection, low sample size, etc) but Kaplan doesn't have any sections on that. Princeton has a small chapter, but it pretty much just gives definitions of variables and such. Or are these questions more common sense?
 
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dickfacedan said:
That's it? ****, I would have guessed higher
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upload_2015-6-17_19-54-44.png
 
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jd989898 said:
3.70. And before people yell at me I mean low for MTSP programs lol. And 520?? Isn't that like 96% in each section
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Lol that's not low! Depends on which school you go to…if you go to like MIT, you'll be absolutely fine! Well, others who had scores lower then yours on the AAMC practice ended up getting 520's +
 
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Got a quick question about processing. So i know that prokaryotes do not do post transcriptional processing because their transcription happens in the cytoplasm.

But what about post translational processing of proteins? Do both eukaryotes and prokaryotes do that?
 
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timsk said:
Got a quick question about processing. So i know that prokaryotes do not do post transcriptional processing because their transcription happens in the cytoplasm.

But what about post translational processing of proteins? Do both eukaryotes and prokaryotes do that?
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Are you talking about proenzymes?
 
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naw, more globally. Some proteins apparently undergo post-translational processing.

But it's not clear to me if only eukaryotes go through that or if both eukaryotes and prokaryotes do. I am assuming yes as translation in both types of cells occur in the cytoplasm. Prokaryotes do not go through post-transcriptional processing because their transcription happens in the cytoplasm versus the nucleus in eukayrotes.
 
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timsk said:
naw, more globally. Some proteins apparently undergo post-translational processing.

But it's not clear to me if only eukaryotes go through that or if both eukaryotes and prokaryotes do. I am assuming yes as translation in both types of cells occur in the cytoplasm. Prokaryotes do not go through post-transcriptional processing because their transcription happens in the cytoplasm versus the nucleus in eukayrotes.
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I guess I am confused as to where this processing would occur. Since membrane bound organelles are inherently involved in that.
 
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Did anyone notice that the EK Exam 2 answer key has a lot of errors? Did they publish a list of errors somewhere on their website so I can match it up??
 
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Can any of you guys explain to me the units for reaction constants?

Like shouldn't second mol*s^-1 not mol^-1 s^-1

Anyone have an intuitive way to explain this? I know how to calculate rate constants and the such but this has eluded me and I've been asked this question on a few passages
 
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mikil100 said:
Can any of you guys explain to me the units for reaction constants?

Like shouldn't second mol*s^-1 not mol^-1 s^-1

Anyone have an intuitive way to explain this? I know how to calculate rate constants and the such but this has eluded me and I've been asked this question on a few passages
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Think about it like this: Rate laws describe the RATE of the reaction (which is measured in Mols/Second). So everything on the right side of the equation must cancel out to M/s.
 
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jd989898 said:
Think about it like this: Rate laws describe the RATE of the reaction (which is measured in Mols/Second). So everything on the right side of the equation must cancel out to M/s.
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Thank you. That is indeed a very intuitive way to look at it
 
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As we all cram last minute info, I thought I may drop this site down... it is a very, very rough outline of some material (sadly doesn't have psych/soc). Just to solidify any of the big topics/look at them quickly.

http://mcat-review.org/
 
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Dang. These Khan Academy Psych Passages are really good. I wish I started working on them earlier.
I thought they would be useless like the Physical Sciences passages.
 
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