B8: Enzyme Kinetics and Cellular Respiration
Official Cambridge & Imperial ESAT specification requirements for Enzyme Kinetics and Cellular Respiration on the Biology paper. Understand the syllabus boundaries, spot distractor traps engineered by examiners, and master the 2-step Sub-90 shortcuts that compress solve time well below the 88.8-second cutoff.
Official Syllabus Subtopics
Requirements specified in the UAT-UK framework
- 1Enzymes as biological catalysts lowering activation energy without being consumed
- 2Active site specificity: lock and key hypothesis vs induced fit hypothesis
- 3Factors affecting rate of enzyme-catalysed reactions: temperature, pH, enzyme and substrate concentrations
- 4Thermal denaturation: excessive thermal vibration breaking hydrogen and ionic tertiary bonds
- 5Competitive inhibition (competing at active site, overcome by high [substrate]) vs non-competitive inhibition (allosteric site binding, reduces Vₘₐₓ)
- 6Aerobic respiration: C₆H₁₂O₆ + 6O₂ ⟶ 6CO₂ + 6H₂O + ATP
- 7Anaerobic respiration in animals (glucose ⟶ lactic acid) vs yeast (glucose ⟶ ethanol + CO₂)
Sub-90 Exam Speed Tips
How top candidates solve this spec under the 88.8s clock
Competitive inhibitors do NOT change Vₘₐₓ (increasing substrate concentration overcomes the inhibitor); non-competitive inhibitors lower Vₘₐₓ.
Denaturation alters tertiary structure irreversibly so the substrate no longer fits the active site.
Examiners engineer distractor options using common algebraic expansions and sign slips. Always test structural ratios or invariants before calculating arithmetic values.
Tested Topics in Specification B8
Master the individual question patterns and Sub-90 shortcuts for this specification.
Enzyme Kinetics, Thermal/pH Denaturation & Aerobic vs. Anaerobic Respiration
Respiration gas check: Mammals (Anaerobic) = 0 O2 in, 0 CO2 out (Lactate only). Yeast (Anaerobic) = 0 O2 in, CO2 out (+ Ethanol). Low temp = low KE (reversible); High temp = active site denatured (irreversible).
Ready to Master Specification B8 Under Exam Conditions?
Practice timed questions under the authentic Pearson VUE interface with live split stopwatch pacing, dry-wipe scratchpad, and distractor forensics.