D2.3.5—Effects on cells without wall
Cells without walls can lyse in hypotonic solutions and crenate in hypertonic solutions because water movement changes cellular volume and shape.
- Syllabus
- First assessment 2025
- Objective
- D2.3.5
- Level
- HL
Exam analysis
Chance of appearing7%of analysed past papers
Latest appearanceNovember 2024
Most common paperPaper3
Typical marks1–2
Common command terms
- Deduce
- Outline
- Predict
- Explain
- Describe
- Suggest
Scoring notes
- Common mistake
- Calling crenated animal cells turgid, a term that applies to walled plant cells.
Recent exam appearances
November 2024Paper3 ["HL"] · TZ02(c)[ 1 ]D2.3.5—Effects on cells without wall
November 2024Paper3 ["HL"] · TZ02(b)[ 3 ]D2.3.5—Effects on cells without wall
May 2023Paper3 ["HL"] · TZ21(b)[ 2 ]D2.3.5—Effects on cells without wall
May 2022Paper1 ["HL"] · TZ22[ 1 ]D2.3.5—Effects on cells without wall
November 2021Paper2 ["HL"] · TZ03(a)[ 1 ]D2.3.5—Effects on cells without wall
Practice this objective
Coverage 2017–2024 · Updated 16 Jul 2026
Concept essentials
- Hypotonic solutions can cause animal cells to swell or lyse.
- Hypertonic solutions can cause animal cells to shrink or crenate.
- Distilled water causes water entry into red blood cells by osmosis.
- Contractile vacuoles expel excess water in freshwater unicellular organisms.