UNE Biochemistry Final Exam Review
UNE medical biochemistry.
Comprehensive Exam Study Guide
2025/2026
A comatose infant is brought to the ER. In the course of the examination, plasma ammonia
was found to be elevated 20-fold over normal values. Urine orotic acid and uracil were both
greater than normal. A defect of which of the following enzymes is the most likely diagnosis?
- ANSOrnithine transcarbamoylase
Your patient presents with a deficiency of the enzyme that catalyzes synthesis of N-
acetylglutamate (NAGs). Which of the following would be a consequence of this deficiency
in the patient? - ANSIncreased amino acids in the blood
The cellular uptake of LDL increases intracellular cholesterol levels. This has which of the
following impacts on de novo cholesterol synthesis? - ANSIncreases degradation of HMG-
CoA reductase
Dietary cholesterol is primarily transported in the body by which of the following
lipoproteins? - ANSChylomicron
Secondary bile salts are generated by bacterial modification of primary bile salts in the
intestinal lumen. These modifications have which of the following impacts on bile salt
solubility? - ANSDecrease solubility
A 47-year-old male is prescribed a statin (HMG-CoA reductase inhibitor) to manage his
elevated LDL cholesterol. What is the initial mechanism of action for obtaining the desired
effect in this man? - ANSDecreasing hepatic cholesterol biosynthesis
A deficiency in the LDL receptor will result in an initial decrease in which of the following? -
ANSIntracellular cholesterol
A 45-year-old man has a mild heart attack and a history of vascular disease. He is placed on a
Mediterranean diet and statin drug therapy. Which of the following will be the most likely
result of this drug therapy? - ANSLow blood LDLs
A 45-year-old man is found to have an elevated serum triglycerides of > 730mg/dL. He tells
you he forgot to fast before his visit and he ate a full breakfast of bacon and eggs before the
labs were drawn. Which of the following lipoproteins would be the largest contributors to a
measurement of plasma triglycerides in this situation? - ANSChylomicrons and VLDLs
In the reaction catalyzed by cholesterol ester transfer protein (CETP), the VLDL particle
receives which of the following compounds from HDL particles? - ANSCholesterol-ester
In reverse cholesterol transport HDL interacts with the ABCA1 transporter to move
cholesterol from the cell to the HDL. This also requires the activity of which of the following
enzyme? - ANSLecithin cholesterol acyltransferase (LCAT)
HDL particles interact with VLDL particles to exchange cholesterol ester for triacylglyerols.
Which of the following enzymes is responsible for this process? - ANSCholesterol ester
transfer protein (CETP)
Which of the following is a major source of extracellular cholesterol for human tissues? -
ANSLDLs
An individual is suspected of having a deficiency in branched chain keto acid dehydrogenase.
Supplementation of which of the following vitamins or cofactors may help resolve this issue?
- ANSThiamine
A 55-year old man presents to his primary care physician with bouts of dizziness and
confusion. He is diagnosed with hyperhomocysteinemia due to a deficiency of cystathionine-
