Ten-Year Series · PSLE 2021
PSLE Science 2021 Answers
The answer key for the PSLE Science 2021 paper (Paper 1): 40 questions, 28 with a free final answer, plus the topic and marks for each. Find the question number in your TYS book and tick it off.
We publish answers only. The questions and diagrams stay in your printed Ten-Year Series (TYS) book, so keep it open beside this page (“see the diagram in your book”).
MCQ answers are option numbers, e.g. (3).
Paper 1
40 questions · 28 free final answers · 100 marks listed
| Q | Answer | Topic / section | Marks |
|---|---|---|---|
| Q1 | (2) | Diversity · Classifying living thingsMCQ | 2 |
| Q2 | (4) | Diversity · Classifying living thingsMCQ | 2 |
| Q3 | (4) | Diversity · MatterMCQ | 2 |
| Q4 | (3) | Systems · Plant transport xylem & phloemMCQ | 2 |
| Q5 | (2) | Cycles · Plant reproductionMCQ | 2 |
| Q6 | (2) | Diversity · Classifying living thingsMCQ | 2 |
| Q7 | (3) | Cycles · Life cycles of animalsMCQ | 2 |
| Q8 | (3) | Systems · Plant transport xylem & phloemMCQ | 2 |
| Q9 | (3) | Cycles · Life cycle of a plantMCQ | 2 |
| Q10 | (3) | Cycles · Life cycles of animalsMCQ | 2 |
| Q11 | (4) | Systems · Human digestive systemMCQ | 2 |
| Q12 | (3) | Energy · Forms of energyMCQ | 2 |
| Q13 | (1) | Diversity · Classifying living thingsMCQ | 2 |
| Q14 | (1) | Cycles · Plant reproductionMCQ | 2 |
| Q15 | (3) | Cycles · Three states of matterMCQ | 2 |
| Q16 | (2) | Cycles · Three states of matterMCQ | 2 |
| Q17 | (4) | Cycles · Changes of stateMCQ | 2 |
| Q18 | (2) | Systems · Series vs parallel circuitsMCQ | 2 |
| Q19 | (4) | Energy · Forms of energyMCQ | 2 |
| Q20 | (3) | Interactions · ForcesMCQ | 2 |
| Q21 | (1) | Diversity · MaterialsMCQ | 2 |
| Q22 | (3) | Systems · Series vs parallel circuitsMCQ | 2 |
| Q23 | (4) | Interactions · ForcesMCQ | 2 |
| Q24 | (3) | Energy · Heat conductors vs insulatorsMCQ | 2 |
| Q25 | (4) | Energy · Light and shadowMCQ | 2 |
| Q26 | (2) | Energy · Heat and temperatureMCQ | 2 |
| Q27 | (4) | Energy · Light and shadowMCQ | 2 |
| Q28 | (3) | Interactions · MagnetsMCQ | 2 |
| Q29 | Model answer in worked solution | Systems · Plant vs animal cellsOpen-ended | 3 |
| Q30 | Model answer in worked solution | Systems · Human respiratory systemOpen-ended | 4 |
| Q31 | Model answer in worked solution | Systems · Human digestive systemOpen-ended | 3 |
| Q32 | Model answer in worked solution | Cycles · Life cycles of animalsOpen-ended | 4 |
| Q33 | Model answer in worked solution | Cycles · Life cycles of animalsOpen-ended | 4 |
| Q34 | Model answer in worked solution | Energy · Forms of energyOpen-ended | 4 |
| Q35 | Model answer in worked solution | Cycles · Changes of stateOpen-ended | 2 |
| Q36 | Model answer in worked solution | Energy · Heat and temperatureOpen-ended | 4 |
| Q37 | Model answer in worked solution | Energy · Forms of energyOpen-ended | 4 |
| Q38 | Model answer in worked solution | Interactions · MagnetsOpen-ended | 5 |
| Q39 | Model answer in worked solution | Cycles · Three states of matterOpen-ended | 3 |
| Q40 | Model answer in worked solution | Energy · Forms of energyOpen-ended | 4 |
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Step-by-step worked solutions for every Science question, written the way PSLE markers award method marks, plus model answers for open-ended questions. We are adding them newest years first (2025 back to 2021), checked against the answer key on this page.
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