Nucleic Acids - Mock Test 56

Question 551

The two nitrogen of the pyrimidine ring are contributed by?

A) Ammonia and glycine B) Asparate and carbamoyl phosphate C) Glutamine and ammonia D) Aspartate and ammonia

---

No Details

Question 552

The two nitrogen of the pyrimidine ring are contributed by?

A) Ammonia and glycine B) Asparate and carbamoyl phosphate C) Glutamine and ammonia D) Aspartate and ammonia

---

No Details

Question 553

The two nitrogen of the pyrimidine ring are contributed by?

A) Ammonia and glycine B) Asparate and carbamoyl phosphate C) Glutamine and ammonia D) Aspartate and ammonia

---

No Details

Question 554

Pyrimidine biosynthesis begins with the formation from glutamine, ATP and CO2, of?

A) Carbamoyl aspartate B) Orotate C) Carbamoyl phosphate D) Dihydroorotate

---

No Details

Question 555

Pyrimidine and purine nucleoside biosynthesis share a common precursor?

A) PRPP B) Glycine C) Fumarate D) Alanine

---

No Details

Question 556

Purine biosynthesis is inhibited by?

A) Aminopterin B) Tetracyclin C) Methotrexate D) Chloramphenicol

---

No Details

Question 557

In the biosynthesis of purine nucleotides the AMP feed back regulates?

A) Adenylosuccinase B) Adenylosuccinate synthetase C) IMP dehydrogenase D) HGPR Tase

---

No Details

Question 558

Conversion of formylglycinamide ribosyl5-phosphate to formyl-glycinamide ribosyl-5-phosphate is inhibited by?

A) Azaserine B) Diazonorleucine C) 6-Mercaptopurine D) Mycophenolic acid

---

No Details

Question 559

PRPP glutamyl amidotransferase, the first enzyme uniquely committed to purine synthesis is feed back inhibited by?

A) AMP B) IMP C) XMP D) CMP

---

No Details

Question 560

An enzyme which acts as allosteric regulator and sensitive to both phosphate concentration and to the purine nucleotides is?

A) PRPP synthetase B) PRPP glutamyl midotransferase C) HGPR Tase D) Formyl transferase

---

No Details