Mini practice paper: 8 questions
Mixed-difficulty questions from across the Integrated Science syllabus. Tap "Show answer" after each to check yourself.
Q1 · Difficulty 1/3
Which gas released from vehicle exhaust combines with haemoglobin in red blood cells, reducing oxygen transport in humans?
- Carbon dioxide
- Carbon monoxide
- Sulphur dioxide
- Nitrogen dioxide
Show answer & explanation
✓ Answer: B — Carbon monoxide
Award 1 mark for carbon monoxide. Carbon monoxide binds to haemoglobin approximately 200 times more strongly than oxygen, forming carboxyhaemoglobin. A is incorrect — CO₂ is transported differently and does not bind permanently to haemoglobin. C is incorrect — SO₂ causes respiratory irritation. D is incorrect — NO₂ causes respiratory problems but does not bind to haemoglobin.
Q2 · Difficulty 1/3
A factory in Trinidad produces plastic bottles from crude oil derivatives. Which term best describes the type of polymer used to make these bottles?
- Synthetic polymer
- Biological polymer
- Organic nutrient
- Natural polymer
Show answer & explanation
✓ Answer: A — Synthetic polymer
Award 1 mark for identifying that plastics made from crude oil derivatives are synthetic polymers. D is incorrect — natural polymers come from living organisms. B is incorrect — while polymers can be biological, plastic bottles are manufactured. C is incorrect — polymers are not classified as nutrients.
Q3 · Difficulty 1/3
Which of the following is the SI unit of energy?
- Newton
- Joule
- Pascal
- Watt
Show answer & explanation
✓ Answer: B — Joule
Award 1 mark for identifying the joule as the SI unit of energy. D is incorrect — watt is the unit of power. A is incorrect — newton is the unit of force. C is incorrect — pascal is the unit of pressure.
Q4 · Difficulty 1/3
Which structure in a plant root is responsible for increasing the surface area for water absorption?
- Phloem tube
- Xylem vessel
- Root hair cell
- Guard cell
Show answer & explanation
✓ Answer: C — Root hair cell
Award 1 mark for identifying root hair cells as extensions that increase surface area. B is incorrect — xylem vessels transport water upward, not absorb it. D is incorrect — guard cells control stomatal opening in leaves. A is incorrect — phloem tubes transport sugars, not water uptake.
Q5 · Difficulty 1/3
Which structure in the male reproductive system is responsible for producing sperm cells?
- Vas deferens
- Prostate gland
- Testes
- Epididymis
Show answer & explanation
✓ Answer: C — Testes
Award 1 mark for identifying testes as the site of sperm production. B is incorrect — the prostate gland produces seminal fluid, not sperm. D is incorrect — the epididymis stores and matures sperm but does not produce them. A is incorrect — the vas deferens is a tube that transports sperm.
Q6 · Difficulty 1/3
What is the difference between renewable and non-renewable energy?
- There is no difference
- Renewable is more expensive
- Renewable sources are replenished naturally; non-renewable will eventually run out
- Non-renewable is cleaner
Show answer & explanation
✓ Answer: C — Renewable sources are replenished naturally; non-renewable will eventually run out
Renewable sources (solar, wind, hydro) are replenished naturally. Non-renewable sources (coal, oil, gas) took millions of years to form and will eventually run out.
Q7 · Difficulty 1/3
A student in Trinidad wants to obtain pure water from a sample of sea water collected at Maracas Bay. Which technique would be MOST suitable?
- Filtration
- Simple distillation
- Decantation
- Evaporation
Show answer & explanation
✓ Answer: B — Simple distillation
Award 1 mark for recognising that distillation allows collection of pure water by evaporating and condensing it, leaving dissolved salts behind. D is incorrect — evaporation would leave the water to escape and only collect the salt. A is incorrect — filtration cannot separate dissolved substances. C is incorrect — decantation separates immiscible liquids or settles solids, not dissolved salts.
Q8 · Difficulty 1/3
What energy conversion occurs during photosynthesis?
- Light energy to chemical energy (stored in glucose)
- Kinetic to potential
- Electrical to light
- Chemical to thermal
Show answer & explanation
✓ Answer: A — Light energy to chemical energy (stored in glucose)
In photosynthesis, plants convert light energy from the sun into chemical energy stored in glucose molecules.
CXC CSEC Integrated Science FAQ
What does the CXC CSEC Integrated Science exam look like?
The CXC CSEC Integrated Science exam is structured across 3 components. Paper 1 (Section A): 60 multiple-choice questions, 1 mark each. 75 minutes. Tests knowledge across the whole syllabus. Paper 2: Structured short-answer + 1 extended response question. Section A is compulsory; Section B has a choice. Approximately 2 hours 10 minutes. School-Based Assessment (SBA): Coursework component graded by the teacher, externally moderated. Worth ~20-30% of the final grade depending on subject. Total exam time: ~3.5 hours across Paper 1 and Paper 2 sittings.
Can I download a free CXC CSEC Integrated Science past paper?
Real CXC past papers are published directly by CXC on their official website. Kramizo doesn't redistribute copyrighted past papers, but we do generate free AI-written practice papers in the exact same style — same command words, same difficulty tier, same mark conventions. Use this practice paper as warm-up, then time yourself on official past papers before exam day.
How is CXC CSEC Integrated Science graded?
Grades: I (highest) to VI (lowest). A grade of III or above is typically required for further study. Kramizo's practice questions are tagged with difficulty 1-3 mapping roughly to the lower, middle, and top grade boundaries you'll encounter in the real exam.