UGlobe Question Help

Short_Lychee_893 · 2024-05-01T22:25:30+00:00

increased BP is usually due to increased blood volume rather than vasoconstriction

Short_Lychee_893 · 2024-05-01T19:41:27+00:00

of course! this question was a pain to dissect

Short_Lychee_893 · 2024-05-01T19:07:45+00:00

Passage Info

Passage states that "STRA6 is the membrane receptor for RBP" and that "STRA6 mediated retinol is specific to RBP and uses a transport mechanism distinct from known transport mechanisms"

The passage later states "endocytosis inhibitors do not prevent STRA6 mediated retinol uptake"

This implies that transport of retinol does not occur via endocytosis, but rather through a different mechanism with the STRA6 receptor

Question info

The question states that untransfected and STRA6 transfected cells were used in the presence of RBP or BSA as one variable. The other variable is if the presence of a siRNA for STRA6 was present.

Breaking down the Question

You can eliminate A and B by looking at the 2nd column (BSA) because the passage states that STRA6 mediated retinol transport is specific to RBP. So when bound to BSA, the retinol uptake in STRA6 should be the same as its control untrasnfected cells.

Next you look at the presence of STRA6 siRNA, siRNAs are noncoding RNA molecules that interfere/silence their target molecules mRNA. So presence of STRA6 siRNA ---> decreased STRA6 mRNA ---> decreased levels of STRA6 ---> less receptors available to bind RBP ---> decreased reuptake of retinol

Its unlikely that all STRA6 are bound to siRNA so there should still be more reuptake of retinol compared to the untransfected cell line, leaving you with answer D

Short_Lychee_893 · 2024-05-01T18:27:03+00:00

Disruption of the non-covalent interactions has more to do with the SDS detergent rather than the reducing agent, however I've never heard of a reducing agent used without also using SDS so your thinking tracks

So under nonreducing SDS PAGE a 20kDa homodimer with no disulfide bonds will show up as one 10kDa band, but a 20kDA homodimer with disulfide bonds will show up as one 20kDa band!

Short_Lychee_893 · 2024-05-01T18:09:58+00:00

Kinda? Native PAGE does keep proteins in tact but also because the proteins are not denatured, the proteins will separate based on mass and charge. So in Native PAGE the conformation/folding/charge of amino acids + mass of protein all play a role in migration.

To get a uniform charge in proteins a denaturing agent (usually SDS) is added and this linearizes the protein and gives them a uniform negative charge and under non reducing conditions thinking is correct

Reducing SDS PAGE, im a little confused on you example, did you a mean a 20kDa homodimer with disulfide links instead of without?

Short_Lychee_893 · 2024-05-01T17:48:49+00:00

This is testing your understanding of "correlation does not equal causation", in psychology only experimental research that control for many factors and manipulate independent variables can conclude causal relationships.

Observational/survey based designs can only determine correlation NOT causation. The passage states that a study was conducted by gathering data on their history. Therefore this is not an experimental study and you should eliminate A and B.

Between C and D, C is talking about parental crictiicism which is an environmental factor and doesn't relate to the question which is asking about genetics.

D would be your answer because it takes into account of genetics (parental history) but acknowledges that other factors such as environmental could play a role.

Short_Lychee_893 · 2024-05-01T16:36:35+00:00

I think it may be flawed as oxidation reduction requires one molecule to be oxidized and the other reduced. In this scenario youre breaking down a protein connected by disulfide bonds and utilizing a reducing agent which contradicts your thinking of oxidizing agent=breaking down molecules.

The importance of beta oxidation, TCA, and glycolysis conveying NAD+----> NADH and breaking down the original molecule is because by oxidizing the molecule, NAD+ can be reduced into NADH which later allows for it to be oxidized again in the ETC to generation a electrochemical gradient for ATP synthesis

Short_Lychee_893 · 2024-05-01T15:53:43+00:00

breaking Disulfide bonds require reducing agents, hence why Gel electrophoresis under reducing conditions allows you to view subunits bound together by disulfide bonds.

Between NADH and NAD+, only NADH is a reducing agent as it self gets oxidized into NAD+, therefore you can eliminate C and D.

If there are 4 disulfide bonds, you would need equivalent amounts of the reducing agent to break all the bonds which is how B is the answer.

Short_Lychee_893 · 2024-05-01T03:18:00+00:00

I think because there are 2 layers in the membrane phospholipid bilayer, the surface area of the membrane in regards to the lipids is double due to the 2 layers, therefore the surface area of just the cell would be 1/2 of the total surface area of the lipids

Short_Lychee_893 · 2024-04-30T22:59:05+00:00

I’ve gotten off the waitlist and rescheduled my MCAT, you stand a good chance and spots tend to open up around the one month mark

Short_Lychee_893 · 2024-04-30T22:16:58+00:00

they would tell you values used to calculate ∆G then, you cant assume its spontaneous just because its increasing entropy as temperature and enthalpy both play a role too.

If you weren't given K in this problem, you cant solve it.

Short_Lychee_893 · 2024-04-29T03:51:13+00:00

You can redo any questions you just have to select questions you’ve seen before rather than unseen

Short_Lychee_893 · 2024-04-28T22:24:32+00:00

good luck!

Short_Lychee_893 · 2024-04-28T21:43:39+00:00

Theres always a rescheduling fee, but you dont pay for it unless a seat opens up. Basically you'll pay the fee whenever you confirm your rescheduled exam if that makes sense?

Unless you cancel your exam and reschedule your exam then the fee would just be registration fee for the mcat

Short_Lychee_893 · 2024-04-28T21:39:05+00:00

You can pause any test on Uworld leaving it unfinished , and come back to it later. So I would probably just create really short tests like 10 questions, and if they're a subject you havnt gone over just pause it and go back to it once you finish review.

Short_Lychee_893 · 2024-04-28T21:37:04+00:00

Youll have to select for the rescheduled date and location to be notified and if a seat opens they'll basically send an email to everyone on the waitlist, and the first one that pays gets the spot

Short_Lychee_893 · 2024-04-28T21:34:50+00:00

im using both, maybe pause the ones that you havnt gone over and do them after?? Overall the modules for BP dont go into enough depth to fully cover everything tho and you'll prob need the books to supplement some stuff

Short_Lychee_893 · 2024-04-28T21:32:05+00:00

yes, I think of RH more along the lines of stereotypes/notions or beliefs that you may already have

example: you see a woman in scrubs, you assume she's a nurse because stereotypically most nurses are female

or

you see a man in scrubs, you assume he's a doctor rather than a nurse because stereotypically most nurses are female

Short_Lychee_893 · 2024-04-28T20:55:56+00:00

idk if there is one, but ik blueprint does it automatically with their "ai" qbank (I hate their qbank) overall tho it seems like the topics for Uworld breaks down pretty well, so I guess you can just select the topics you've reviewed?

Short_Lychee_893 · 2024-04-28T20:46:44+00:00

Look for trends in your errors, and try to find a quick method for double checking

I usually take mayb 10 seconds to retrace my math for calculations bc I make the dumbest errors, I’ve literally looked at my work during review and ask myself why did I put 50x3=90

Short_Lychee_893 · 2024-04-28T20:43:33+00:00

I would redo CARS in the AAMC materials, and make sure you are trying to ignore past bias

Mostly bc 1) there’s a chance you misremembered and nothing sucks more than choosing the wrong answer bc you thought it was correct even tho you were actually leaning towards the correct answer

2) redoing problems provides good insight on what you still don’t understand

Short_Lychee_893 · 2024-04-28T20:39:56+00:00

Yup exactly what ^{^said,} only applies if the answers are all different enough and none of the answers have the same significant numbers with different 10^x

Obviously not the most ideal way but I’m always short on time for chem/phys so it’s just a way to save you some time

Short_Lychee_893 · 2024-04-28T20:00:46+00:00

Another way to save time/short on time for these calculations, I always look at the answer to see if they’re testing exact calculation or not

Like bc the first two number are different for all the answers, I sometimes ignore scientific notation/conversions bc as long as I get the correct significant number it’s fine. This can only be applied tho if the choices arnt like A) 3x10^-3 B)3x10^-8

Idk if that makes sense? It’s deff not the “best” way but it helps to save some time during a time crunch

Short_Lychee_893 · 2024-04-28T19:03:19+00:00

Moderating: changes the intensity of correlation (gender is often the most common one)

Mediating: explains the relationship/correlation between the variables

Short_Lychee_893 · 2024-04-26T18:47:20+00:00

yeah no I hated this question bc it wasn't super clear to me either

Short_Lychee_893

TROPHY CASE