Take Your Vitamins
A severely malnourished patient develops fatigue, irritability, and painful burning feet. The deficient vitamin is required for synthesis of coenzyme A. Which vitamin is deficient?
Pantothenic acid (B5)
Fetal hemoglobin has greater O₂ affinity partly because it binds what molecule less strongly?
2,3-BPG
After collagen secretion, lysyl oxidase requires which mineral for cross-link formation?
Copper
A PPAR-α agonist increases LPL activity to treat severe hypertriglyceridemia. What class of drug is this?
Fibrate
Adenine + ribose without phosphate is what type of molecule?
Nucleoside
A malnourished child develops peripheral edema and fatty liver due partly to decreased albumin and apolipoprotein synthesis. What is the diagnosis?
Kwashiorkor
A patient with ethylene glycol poisoning receives a drug that inhibits alcohol dehydrogenase.
Fomepizole
A child has hepatomegaly and mild fasting hypoglycemia with glycogen containing abnormally short outer branches. Which enzyme is deficient?
Debranching enzyme — Cori disease
Cirrhosis, diabetes, bronze skin, and MCP arthropathy suggest what diagnosis?
Hemochromatosis
BRCA1/2 mutations impair which high-fidelity double-strand break repair pathway?
Homologous recombination
A patient with fat malabsorption develops neurologic dysfunction and hemolytic anemia due to oxidative membrane damage. Which vitamin is deficient?
Vitamin E
Which assay uses an enzyme-linked antibody and a color-producing substrate?
ELISA
Even after several days of starvation, which cells remain completely glucose-dependent?
RBCs
A young adult has markedly elevated LDL, tendon xanthomas, and premature CAD. Which receptor is classically defective?
LDL receptor
Early colorectal cancer plus a family history of endometrial, ovarian, and gastric cancers suggests failure of which repair pathway?
Mismatch repair / Lynch syndrome
Dietary folate is absorbed primarily in which portion of the small intestine?
Jejunum
This somatostatin analog can be used in treatment of Zollinger-Ellison syndrome when proton pump inhibitors aren't doing the job.
Octreotide
In ADA-deficient SCID, accumulated dATP directly inhibits which enzyme required for DNA precursor synthesis?
Ribonucleotide reductase
Low hepcidin causes persistent activity of which iron transporter?
Ferroportin
Cytosine deaminates to uracil. Which repair pathway removes the abnormal base?
Base excision repair
A child with defective neutral amino acid transport develops a photosensitive rash and neurologic symptoms. Decreased absorption of which amino acid causes the associated vitamin deficiency?
Tryptophan
Which chemotherapy drug class prevents microtubule depolymerization?
Taxanes
Which enzyme forms leukotrienes from arachidonic acid?
5-lipoxygenase
Which sphincter controls bile and pancreatic secretion through the hepatopancreatic ampulla into the duodenum? It is also known as the hepatopancreatic sphincter.
Sphincter of Oddi
Which cyclin binds CDK4/6 during G1 and promotes Rb phosphorylation?
Cyclin D