Why is the answer A?
Thanks,
Thanks,
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Step I NBME3 spoiler physio question
Started by Phloston
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Yeah, but isn't B also hypotonic?
Plasma osmolarity should be 290 mOsm.
Why is it specifically A?
Plasma osmolarity should be 290 mOsm.
Why is it specifically A?
Wait...if I hear what you're saying: 2 MOLES of ions x 150 mOsm = 300 mOsm, then B would be ~isotonic, right?
I can understand that A is hypotonic, but I just want to know that the above logic is right.
Nothing like pulling a little gen chem back out of the closet.
I can understand that A is hypotonic, but I just want to know that the above logic is right.
Nothing like pulling a little gen chem back out of the closet.
there are quite a bit of gen chem and some surprise orgo questions on the uslme. this is something that is covered in physiology though and yes I did mean hypertonic (though only slightly).
Solution would be hypotonic, in this case, half of that of RBC, so 300/2 = 150, but keep in mind, every one NaCl formula unit breaks down into 2 ions: Na+ & Cl-, so 150/2 = 75.
Yeah, I realize the simplicity of the question now. Kind of a joke, really, when you think about it.
