Amino Acids & Proteins MCAT Practice Questions
15 board-style MCAT questions in Biological & Biochemical Foundations (B/B). Each question shows the correct answer; create a free account for the full explanation and adaptive practice.
- MCAT · medium1. A 34-year-old woman with a history of recurrent bacterial infections undergoes genetic testing, which reveals a mutation in the CTSC gene encoding cathepsin C, a serine protease…
- MCAT · medium2. A 28-year-old man presents with progressive muscle weakness and cognitive decline. Genetic testing reveals a point mutation in the SELENOP gene that converts a tryptophan codon…
- MCAT · medium3. A 24-year-old man of African descent presents to the emergency department with acute chest pain, dyspnea, and fever. Laboratory studies reveal hemoglobin concentration of 8.2 g/…
- MCAT · medium4. A 34-year-old man with a history of recurrent infections presents with progressive neurological decline, muscle weakness, and cognitive impairment over the past 6 months. Brain…
- MCAT · medium5. A 34-year-old woman with a history of recurrent respiratory infections undergoes genetic testing and is found to have a mutation in the CFTR gene that results in a 27-amino acid…
- MCAT · medium6. A 6-year-old boy with cystic fibrosis presents with recurrent pulmonary infections and pancreatic insufficiency. Genetic testing reveals a nonsense mutation in the CFTR gene res…
- MCAT · medium7. A biochemist studies a membrane protein with seven transmembrane helices. Analysis reveals that the hydrophobic core of each helix contains primarily leucine, isoleucine, and va…
- MCAT · medium8. A 68-year-old man with progressive memory loss and cognitive decline is found to have amyloid-beta (Aβ) plaques on autopsy. Researchers studying his brain tissue measure the pH…
- MCAT · medium9. A patient presents with a mutation in the gene encoding glycine-rich collagen, where 15% of all glycine residues are replaced with alanine. Glycine is the smallest amino acid wi…
- MCAT · medium10. A biochemist characterizes a mutant enzyme and finds that substituting leucine with aspartate at a critical position reduces enzyme activity to 5% of wild-type levels. The enzym…
- MCAT · medium11. A 68-year-old man presents with progressive dementia, ataxia, and myoclonus over the past 8 months. MRI shows characteristic spongiform changes in the cerebral cortex and basal…
- MCAT · medium12. A 58-year-old woman with pernicious anemia presents with progressive paresthesias, ataxia, and cognitive decline. Laboratory studies reveal elevated serum homocysteine (42 μmol/…
- MCAT · medium13. A 34-year-old man presents with progressive muscle weakness, tremor, and cognitive decline. Laboratory studies reveal low plasma selenium levels and elevated thyroid peroxidase…
- MCAT · medium14. A researcher studying protein misfolding discovers that a mutation in the CFTR protein replaces a phenylalanine residue with a serine in the nucleotide-binding domain. This muta…
- MCAT · medium15. A researcher studying protein structure finds that a particular amino acid residue at position 47 of an enzyme forms a disulfide bond with residue 83. The enzyme loses activity…