Nucleotide Metabolism

Question 1

T/F. Nucleic acids are like amino acids in that they can be obtained from nutrients.

Answer 1

False.

Nucleic acids are synthesized independently in the body.

Question 2

What are the two paths of nucleotide biosynthesis?

Answer 2

De Novo and Salvage pathways

Question 3

Hepatocytes often follow the ______ pathway for nucleotide biosynthesis while the rest of the body’s cells follow the ______ pathway.

Answer 3

de novo, salvage

Question 4

DNA replication is happening constantly in the body. How many nucleic acids can be found in the cellular pool?

Answer 4

Not a lot. Synthesis must occur constantly

Question 5

Because purine and pyrimidine synthesis are constantly occurring, stopping these biosynthesis pathways leads to what?

Answer 5

Disease, cancer, dangerous.

Question 6

What amino acid is central to purine and pyrimidine biosynthesis?

Answer 6

Glutamine

Question 7

In the purine de novo pathway, what is the first committed step?

Answer 7

Amino acid group dedication (Glucoses)

Question 8

What are the three main steps in the purine de novo pathway?

Answer 8

1. Glu dedication
2. PRPP regulatory step
3. Tetrahydrofolate to dihydrofolate

Question 9

Cancer drugs can target ______ recycling which would inhibit both purine and pyrimidine formation.

Answer 9

Tetrahydrofolate

Question 10

What molecule acts as a precursor for both AMP and GMP?

Answer 10

IMP

Question 11

How are GMP and ATP related in the purine de novo pathway?

Answer 11

The formation of ATP requires GTP. The formation of GTP relies on enough GMP formation at the end of the pathway.
Same for AMP and GTP