MCAT® ExamBiological and Biochemical Foundations of Living SystemsEasy
A biochemist is studying a newly discovered protein that exhibits catalytic activity. They observe that this protein significantly speeds up a specific biochemical reaction without being consumed in the process. Furthermore, the protein shows high specificity for its substrate and functions optimally within a narrow pH and temperature range. What general class of biomolecules does this protein belong to?
- ANucleic acids
- BCarbohydrates
- CEnzymes
- DLipids
Show answer & explanationAnswer & explanation
Correct answer: C. Enzymes
The description of a protein that exhibits catalytic activity, speeds up reactions without being consumed, shows substrate specificity, and has optimal pH/temperature ranges are all defining characteristics of enzymes, which are biological catalysts.
Why the other options are wrong
- A. Nucleic acids (DNA/RNA) carry genetic information and are involved in protein synthesis.
- B. Carbohydrates are primarily for energy storage and structural support.
- D. Lipids are involved in energy storage, membrane structure, and signaling.
Enzyme Characteristics
Enzymes are biological catalysts, primarily proteins, that accelerate the rate of biochemical reactions without being consumed in the process. They exhibit high specificity for their substrates and are sensitive to changes in pH and temperature.
- Are biological catalysts (mostly proteins).
- Speed up reaction rates.
- Are not consumed in the reaction.
- Highly specific for their substrates.
- Function optimally within specific pH and temperature ranges.
Memory trick: Enzymes: The protein workers, speeding up the factory.