BIOCHEMISTRY COMPILED EXPECTED
EXAM QUESTIONS AND THEIR CORRECT
ANSWERS
Histones are _________ Charged and are rich in
_________ Amino Acids
- Positively
- Lysine and Arginine "LA"
DNA Methylation occurs on which Nucleotides?
Cytosine and Adenine
Cytosine is _________ and turned to Uracil
Deaminated
Cytosine → Uracil
Add ________ to Uracil to form _________
Methyl Group
Thymine
Uracil → Thymine
Purine Synthesis requires
GAG
- Glycine
- Aspartate
- Glutamine
Pyrimidine Synthesis Requires
- Aspartate
- Carbamoyl Phosphate
,- Leflunomide Function?
- Used to Treat?
- Inhibits Dihydroorotate Dehydrogenase
Treat:
- Rheumatoid Arthritis
Methotrexate (MTX),
Trimethoprim (TMP),
Pyrimethamine
Function?
- Inhibit Dihydrofolate Reductase
- ↓DTMP
- 5-Fluorouracil (5-FU) Function?
Inhibits Thymidylate Synthase
- Forms 5F-dUMP
- Inhibits Thymidylate Synthase
- ↓DTMP
Why do you prescribe Folate (Leucovorin) with both 5-
FU and MTX/TMP?
- Folate Increases the Potency of 5-FU
- Reduces the Side Effects of MTX/TMP
- 6-Mercaptopurine (6-MP) Function?
- Used to Treat?
- Inhibit De Novo Purine Synthesis
- Along with it's Prodrug: Azathioprine
Treat:
- Rheumatoid Arthritis
,- Leukemias
- Inflammatory Bowel Diseases
6-Mercaptopurine (6-MP) is inhibited by?
XO (Xanthine Oxidase)
Mycophenolate, Ribavirin Function?
- Inhibits Inosine Monophosphate Dehydrogenase
Mycophenolate Used to Treat?
Organ Transplant to Prevent Rejection
- Ribavirin Used to Treat?
- Influenza
- Hepatitis C
- Hydroxyurea Function?
- Inhibits Ribonucleotide Reductase
- Inhibits DNA Synthesis
Hydroxyurea is used to treat?
- Sickle Cell Anemia
- Patients with SCA have a mutation in Adult
Hemoglobin, causing Sickling
- Hydroxyurea inreases the production of Fetal
Hemoglobin, reducing Sickling
Xanthine Oxidase is inhibited by?
Allopurinol
Febuxostat
Allopurinol/Febuxostat are used to treat?
Lesch-Nyhan Syndrome
Lesch-Nyhan Syndrome mode of transmission?
X-Linked Recessive
Lesch-Nyhan Syndrome
- Defect:
, - Results:
- Symptoms:
Defect:
- HGPRT
Results in:
- Excess Uric Acid Production
- Compensated Excess De Novo Purine Synthesis
Symptoms:
- H: Hyperuricemia
- G: Gout
- P: Pissed Off/Aggressive/Self Mutilation
- R: Retardation (Mental)
- T: DysTonia
What's a classic finding of Lesch-Nyhan Syndrome
Deficiency seen in diapers?
- Yellow-Orange Granules
- Represent Uric Acid Crystals
Lesch-Nyhan Syndrome Deficiency leads to what
specific blood smear?
- Lack of HGPRT causes inactivation of the purine salvage
pathway, which prevents Guanine and Hypoxanthine from
being recycled to GMP and IMP.
- Since Guanine and Hypoxanthine are lost as uric acid,
the De Novo 'Purine' Synthesis Pathway must
Compensate
- Thus, it utilizes Folate & Vitamin B12
EXAM QUESTIONS AND THEIR CORRECT
ANSWERS
Histones are _________ Charged and are rich in
_________ Amino Acids
- Positively
- Lysine and Arginine "LA"
DNA Methylation occurs on which Nucleotides?
Cytosine and Adenine
Cytosine is _________ and turned to Uracil
Deaminated
Cytosine → Uracil
Add ________ to Uracil to form _________
Methyl Group
Thymine
Uracil → Thymine
Purine Synthesis requires
GAG
- Glycine
- Aspartate
- Glutamine
Pyrimidine Synthesis Requires
- Aspartate
- Carbamoyl Phosphate
,- Leflunomide Function?
- Used to Treat?
- Inhibits Dihydroorotate Dehydrogenase
Treat:
- Rheumatoid Arthritis
Methotrexate (MTX),
Trimethoprim (TMP),
Pyrimethamine
Function?
- Inhibit Dihydrofolate Reductase
- ↓DTMP
- 5-Fluorouracil (5-FU) Function?
Inhibits Thymidylate Synthase
- Forms 5F-dUMP
- Inhibits Thymidylate Synthase
- ↓DTMP
Why do you prescribe Folate (Leucovorin) with both 5-
FU and MTX/TMP?
- Folate Increases the Potency of 5-FU
- Reduces the Side Effects of MTX/TMP
- 6-Mercaptopurine (6-MP) Function?
- Used to Treat?
- Inhibit De Novo Purine Synthesis
- Along with it's Prodrug: Azathioprine
Treat:
- Rheumatoid Arthritis
,- Leukemias
- Inflammatory Bowel Diseases
6-Mercaptopurine (6-MP) is inhibited by?
XO (Xanthine Oxidase)
Mycophenolate, Ribavirin Function?
- Inhibits Inosine Monophosphate Dehydrogenase
Mycophenolate Used to Treat?
Organ Transplant to Prevent Rejection
- Ribavirin Used to Treat?
- Influenza
- Hepatitis C
- Hydroxyurea Function?
- Inhibits Ribonucleotide Reductase
- Inhibits DNA Synthesis
Hydroxyurea is used to treat?
- Sickle Cell Anemia
- Patients with SCA have a mutation in Adult
Hemoglobin, causing Sickling
- Hydroxyurea inreases the production of Fetal
Hemoglobin, reducing Sickling
Xanthine Oxidase is inhibited by?
Allopurinol
Febuxostat
Allopurinol/Febuxostat are used to treat?
Lesch-Nyhan Syndrome
Lesch-Nyhan Syndrome mode of transmission?
X-Linked Recessive
Lesch-Nyhan Syndrome
- Defect:
, - Results:
- Symptoms:
Defect:
- HGPRT
Results in:
- Excess Uric Acid Production
- Compensated Excess De Novo Purine Synthesis
Symptoms:
- H: Hyperuricemia
- G: Gout
- P: Pissed Off/Aggressive/Self Mutilation
- R: Retardation (Mental)
- T: DysTonia
What's a classic finding of Lesch-Nyhan Syndrome
Deficiency seen in diapers?
- Yellow-Orange Granules
- Represent Uric Acid Crystals
Lesch-Nyhan Syndrome Deficiency leads to what
specific blood smear?
- Lack of HGPRT causes inactivation of the purine salvage
pathway, which prevents Guanine and Hypoxanthine from
being recycled to GMP and IMP.
- Since Guanine and Hypoxanthine are lost as uric acid,
the De Novo 'Purine' Synthesis Pathway must
Compensate
- Thus, it utilizes Folate & Vitamin B12
