Urea cycle!

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Urea cycle!

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medikus
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Posts: 97

05/31/08 - 11:56 AM

An infant has inherited defect in ornithine transcarbamoylase is most likely to have na increase in plasma concentration of :
a) urea
b) arginine
c) ammonia
d) citruline
e) putrescine

Please, any help is apreciated!

Jackofknives
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05/31/08 - 12:06 PM

c

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Guyton
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06/04/08 - 10:39 AM

answer is C ammonia

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hitesh
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06/05/08 - 07:58 AM

c) ammonia

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Melu
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06/10/08 - 12:37 AM

The answer is C.Ammonia.

In the urea cycle in the liver , Ammonium ion+CO2------> urea.(END PRODUCT)

Since there is a deficiency of enzyme ornithine transcarbamoylase the subsequent products citrulline, Arginine and Urea are not formed.

So the plasma concentration of Ammonia increases.

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GOGETA
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06/15/08 - 11:05 AM

Dude the only thing I remember from this crap of bioch. is that ammonia is bad for you.
your body takes ammonia in the liver and transform it in UREA so you can pee it out.

Also remember that urea is need it for ADH to work.

Ammonia bad for the brain.

learn everything about the UREA cycle very HY for step 1

I HATE BIOCHEMISTRY

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peter90036
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06/24/08 - 02:26 PM

bioch !!!!

hahaha good one gogeta

(resemblance to biotch/biatch)

usmlekiller
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06/25/08 - 04:40 AM

peter90036 wrote:
bioch !!!!

hahaha good one gogeta

(resemblance to biotch/biatch)

hahhahhhaha smiling face

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Karime
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06/30/08 - 10:18 PM

Answer C
There's a chart In kaplan lecture notes:

GENETIC DEFICIENCIES OF UREA SYNTHESIS:
Carbamoyl phosphate synthetase deficiency and Ornithine transcarbamoylase:
- both mitochondrial enzimes
- clinical manifestations: hyperammonemia, glutamine increased, BUN decreased, cerebral edema and lethargy, conuvulsions, coma and death.

But only in Ornithine transcarbamoylase URACIL AND OROTIC ACID ARE INCREASED IN BLOOD AND URINE

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