Biochem 13 NBME

Prep for USMLE Forum

» Log in | Register

Forum

Step 1

Match

Prep4USMLE Forum » USMLE Step 1 Forum » Biochemistry Forum

Biochem 13 NBME

Author

10 Posts

DrVirgo
Forum Hero
avatar

Topics: 1096
Posts: 3,515

02/14/06 - 07:59 AM

(Cleft lip picture)…..The developmental anomaly shown in this stillborn fetus is most commonly characterized by which type of inheritance?

A) Autosomal dominant

B) Autosomal recessive

C) Mitochondrial

D) Multifactorial

E) Sex-linked

15. In gout, hyperuricemia resulting from overproduction of urate is most likely to result from a lack of feedback inhibition by ADP or GDP at which enzyme?

A) Adenosine deaminase

B) Dihydrofolate reductase

C) Glucose 6-phosphate dehydrogenase

D) Nucleotide phosphorylase

E) Phosphoribosylpyrophosphate synthetase

___________________
Our greatest glory is not in never falling, but in rising every time we fall.

reet
Forum Fanatic
avatar

Topics: 152
Posts: 1,411

02/14/06 - 08:38 AM

1. D

2. E

___________________
Live as u were to die tommorow. Learn as if u were to live forever.

robin082006
Forum Hero
avatar

Topics: 471
Posts: 5,123

02/14/06 - 08:58 AM

___________________
The Key to Succeed is Patience.

nadiabarati

02/14/06 - 09:07 AM

1.D

2.?

nadiabarati

02/14/06 - 09:07 AM

1.D

2.A?

DrVirgo
Forum Hero
avatar

Topics: 1096
Posts: 3,515

02/15/06 - 07:57 AM

Can anyone explain the second question please?

___________________
Our greatest glory is not in never falling, but in rising every time we fall.

tn1kinobe
Forum Newbie

Topics: 0
Posts: 21

09/13/06 - 11:59 PM

DrVirgo wrote:
Can anyone explain the second question please?

Think of HGPRT. E is the closest u can get to it if u know what HGRPT stands for. CLue? THink of Lesch-nyhan syndrome about self-mutilation and gout.

docarchana
Forum Guru

Topics: 70
Posts: 515

09/14/06 - 12:10 AM

for the second q, i think nbme has given wrong choice. PRPP amido transferase is the actual enzyme.

klimt
Forum Guru

Topics: 27
Posts: 605

09/21/06 - 04:06 PM

But still E is as close as it gets

___________________
Traveler, there are no roads. Roads are made by walking.

eytanraz
Forum Newbie

Topics: 1
Posts: 68

09/25/06 - 09:43 AM

#10

No doubts, the answer is E:

-Firs Aid 2006 page 320: it says that gout can be caused by PRPP excess.

-Lippincott Biochemistry 3rd edition page 291, it says that phosphoribosilpyrophosphate synthetase is inhibited by purine ribonucleotides.

You don't have permission to post.