Q BankQuestion BankDocsDocuments

C1.1.11 (HL)—Intracellular vs. extracellular enzymes

Intracellular enzymes work inside cells, whereas extracellular enzymes are secreted to catalyse reactions outside cells, including chemical digestion in organisms.

Syllabus
First assessment 2025
Objective
C1.1.11
Level
HL

Exam analysis

Chance of appearing4%of analysed past papers
Latest appearanceMay 2025
Most common paperPaper1
Typical marks1–3

Common command terms

  • Explain
  • Discuss
  • Outline
  • State
  • Identify

Recent exam appearances

May 2025Paper1A ["HL"] · TZ16[ 1 ]C1.1.11 (HL)—Intracellular vs. extracellular enzymes
May 2023Paper1 ["HL"] · TZ119[ 1 ]C1.1.11 (HL)—Intracellular vs. extracellular enzymes
May 2017Paper1 ["HL"] · TZ123[ 1 ]C1.1.11 (HL)—Intracellular vs. extracellular enzymes
November 2014Paper3 ["HL"] · TZ015[ 6 ]C1.1.11 (HL)—Intracellular vs. extracellular enzymes
May 2013Paper3 ["HL"] · TZ1H2(c)[ 3 ]C1.1.11 (HL)—Intracellular vs. extracellular enzymes
Practice this objective

Coverage 2013–2025 · Updated 15 Jul 2026

Concept essentials

  • Intracellular enzymes catalyse reactions inside cells.
  • Extracellular enzymes are secreted and act outside cells.
  • Pancreatic enzymes digest starch, lipids and proteins in the small intestine.
  • Inactive protease precursors help prevent self-digestion.
ConceptIB Biology HL