MCAT (Medical College Admission Test) · Biological and Biochemical Foundations of Living Systems
Biochemistry and Molecular Biology
41 practice questions, each with the answer and an explanation.
Practise Biochemistry and Molecular Biology now
Random questions from this topic, one at a time. You see the answer and the explanation straight after each one.
All 41 questions
- Which amino acid has no stereocenter and is therefore achiral?
- Which enzyme catalyzes the rate-limiting step of glycolysis?
- A competitive inhibitor is added to an enzyme reaction. How are the apparent Km and Vmax affected?
- A noncompetitive inhibitor is added to an enzyme reaction. How are the apparent Km and Vmax affected?
- What is the net yield of ATP from the glycolysis of one glucose molecule?
- Where in the cell does the electron transport chain operate in eukaryotes?
- Which molecule is the final electron acceptor of the electron transport chain?
- Which process in the liver is stimulated by insulin after a meal?
- Which type of reaction forms a peptide bond between two amino acids?
- An amino acid is dissolved in a solution whose pH is below its isoelectric point (pI). What is its net charge?
- In Michaelis-Menten kinetics, what is the reaction velocity when the substrate concentration equals Km?
- Which enzyme converts oxaloacetate to phosphoenolpyruvate in gluconeogenesis?
- Where does the beta-oxidation of fatty acids take place?
- Which lipoprotein carries cholesterol from the liver to peripheral tissues?
- A protein has a Hill coefficient greater than 1. What does this indicate about ligand binding?
- During DNA replication, how is the leading strand synthesized?
- Which enzyme removes the RNA primers and fills the gaps in prokaryotic DNA replication?
- Which nitrogenous base is found in RNA but not in DNA?
- How many ATP are consumed in the preparatory (investment) phase of glycolysis per glucose?
- Which sugar is a component of RNA?
- Which hormone stimulates glycogen breakdown in the liver during fasting?
- Which vitamin is a cofactor for carboxylation reactions such as pyruvate carboxylase?
- Which type of inhibitor increases the apparent Km without changing Vmax?
- Which enzyme of the citric acid cycle is also a component of the electron transport chain (Complex II)?
- Which enzyme synthesizes the RNA primer during DNA replication?
- What is the net yield of ATP from one molecule of glucose in anaerobic glycolysis?
- The Michaelis constant Km is defined as the substrate concentration at which
- Which process produces NADPH in the cytosol?
- Where does the urea cycle begin?
- In the lac operon, what happens when lactose is present and glucose is absent?
- A mutation changes a codon from UAU to UAA. What type of mutation is this?
- Which level of protein structure is stabilized mainly by hydrogen bonds between backbone atoms?
- Which molecule shuttles acetyl units from the mitochondria to the cytosol for fatty acid synthesis?
- A transcription factor binds to a DNA sequence far from a gene and increases its transcription. What is this sequence called?
- Which of the following is the rate-limiting enzyme of cholesterol synthesis?
- Which fatty acid is an essential fatty acid for humans?
- Which bond links amino acids in a polypeptide chain?
- Which molecule is the immediate electron acceptor at the end of the electron transport chain?
- Which amino acid is most likely to be found on the interior of a folded globular protein in water?
- Which technique separates proteins by size using a polyacrylamide gel and a denaturing detergent?
- Which statement about allosteric enzymes is true?