Biochemistry - MCQ Practice Questions

Which enzyme belongs to the transferase class (EC 2)?

A patient has elevated serum creatine kinase (CK). Which tissue type is primarily affected?

Which prosthetic group is found in cytochrome c oxidase?

In a temperature vs. enzyme activity graph, why does enzyme activity decrease above the optimal temperature?

Which proteolytic enzyme is responsible for activating trypsinogen to trypsin in the small intestine?

A researcher studying protein folding observes that a newly synthesized polypeptide chain contains multiple disulfide bonds between cysteine residues. Which cellular compartment is most likely responsible for facilitating the formation of these disulfide bonds?

An enzyme exhibits a Km of 2 mM and Vmax of 100 μmol/min. When substrate concentration is 6 mM and an allosteric inhibitor is added, the Vmax decreases to 50 μmol/min while Km remains unchanged. What type of inhibition is occurring?

The Maillard reaction occurs between reducing sugars and amino acids, leading to the formation of:

In hyperglycemia, excess glucose undergoes polyol pathway conversion. Which enzyme catalyzes the first step?

Which of the following is a branching enzyme in glycogen synthesis?

Cori cycle involves recycling of lactate from muscles to liver. Which enzyme is key in converting lactate back to glucose in the liver?

The anomeric carbon in glucose is:

HbA1c levels are used to monitor long-term glycemic control because glucose binds to hemoglobin through:

Cellulose differs from starch in that it contains:

In the pentose phosphate pathway, the oxidative phase primarily generates:

In diabetes mellitus type 2, impaired fasting glucose (100-125 mg/dL) is associated with:

Which of the following statements is TRUE about the Cori cycle?

A patient presents with lactic acidosis after consuming alcohol. Which enzyme's inhibition by acetaldehyde is primarily responsible for this condition?

Which monosaccharide is the primary carbon source for synthesis of heparin and other glycosaminoglycans?

In the pentose phosphate pathway, which intermediate can directly feed into glycolysis as glyceraldehyde-3-phosphate?