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Old 02-04-2012
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Calculator Calculation of Plasma Volume?

The rapid ingestion of 1200 mL of water will cause the plasma volume to increase by how many mL?

A. 720 mL
B. 480 mL
c. 400 mL
D. 100 mL
E. 50 mL

Please help!
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Old 02-04-2012
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Ans C ........ 1/3 will remain in plasma , as it appears to be pure water , which is not isotonic and will diffuse intracellularly by 2/3 ...
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Quote:
Originally Posted by Hitman View Post
Ans C ........ 1/3 will remain in plasma , as it appears to be pure water , which is not isotonic and will diffuse intracellularly by 2/3 ...
the answer is actually D I dont know how to derive to it
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dont know how to get 100 ml either .......
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Old 02-05-2012
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out of 1200ml -1/3rd will be in extracellular and 2/3rd will move into intracellular

1/3rd extracellular =400ml

extracellular is comprised of 1/4th plasma volume and 3/4 interstitial volume

so plasma vol=1/4 multiplied by 400 =100ml

Thanks for the question
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Quote:
Originally Posted by step_enhancer View Post
out of 1200ml -1/3rd will be in extracellular and 2/3rd will move into intracellular

1/3rd extracellular =400ml

extracellular is comprised of 1/4th plasma volume and 3/4 interstitial volume

so plasma vol=1/4 multiplied by 400 =100ml

Thanks for the question

thank u very much!!!!
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Old 02-05-2012
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Quote:
Originally Posted by step_enhancer View Post
out of 1200ml -1/3rd will be in extracellular and 2/3rd will move into intracellular

1/3rd extracellular =400ml

extracellular is comprised of 1/4th plasma volume and 3/4 interstitial volume

so plasma vol=1/4 multiplied by 400 =100ml

Thanks for the question

Sorry to disappoint , but rule is 2/3 and 2/3 ,intracellular and interstitial respectively (source Kaplan physiology chapter 1) exact answer 133 taking rough round off goes to 100.
Correct me if I am wrong.
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Quote:
Originally Posted by Kabutar111 View Post
Sorry to disappoint , but rule is 2/3 and 2/3 ,intracellular and interstitial respectively (source Kaplan physiology chapter 1) exact answer 133 taking rough round off goes to 100.
Correct me if I am wrong.
well FA says 2/3 and 3/4 for intralcellular and interstitial fluid ...... renal system pg 459 2011 edition ........

the ans is exactly 100 .........
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Quote:
Originally Posted by Hitman View Post
well FA says 2/3 and 3/4 for intralcellular and interstitial fluid ...... renal system pg 459 2011 edition ........

the ans is exactly 100 .........
I am doomed another fact difference between two.
Doesn't make difference here but another set of values and I am doomed to be wrong .
Thx for thumbs up
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