Mini practice paper: 8 questions
Mixed-difficulty questions from across the Biology syllabus. Tap "Show answer" after each to check yourself.
Q1 · Difficulty 1/3
An oil spill harms seabirds directly because oil on their feathers:
- Destroys the waterproofing and insulation
- Improves their buoyancy
- Increases their flight speed
- Provides extra nutrients
Show answer & explanation
✓ Answer: A — Destroys the waterproofing and insulation
Oil makes feathers clump together, so they no longer trap air. The bird loses insulation and buoyancy and may die of cold or drowning.
Q2 · Difficulty 1/3
Clearing vegetation from land close to the coast damages coral reefs mainly because it increases:
- Sediment washed into the sea
- Wind speed over the reef
- Salinity of the ocean
- Depth of the water
Show answer & explanation
✓ Answer: A — Sediment washed into the sea
Without plant roots to hold the soil, rain washes sediment into the sea. The sediment settles on corals and blocks the light their algae need.
Q3 · Difficulty 1/3
A chemical applied to crops specifically to kill insect pests is a:
- Fertiliser
- Herbicide
- Pesticide
- Decomposer
Show answer & explanation
✓ Answer: C — Pesticide
Pesticides kill pests such as insects. Herbicides kill weeds and fertilisers supply mineral nutrients.
Q4 · Difficulty 2/3
Protecting natural resources and wildlife for the future is called:
- pollution
- conservation
- deforestation
- urbanisation
Show answer & explanation
✓ Answer: B — conservation
Conservation protects the environment.
Q5 · Difficulty 2/3
Sewage and chemicals entering rivers cause ____ pollution.
- air
- water
- noise
- light
Show answer & explanation
✓ Answer: B — water
They cause water pollution.
Q6 · Difficulty 2/3
Fertiliser running into a pond eventually lowers the oxygen concentration because:
- Algae stop photosynthesising immediately
- The water evaporates more quickly
- Decomposers use up oxygen breaking down dead algae
- Fish release extra carbon dioxide
Show answer & explanation
✓ Answer: C — Decomposers use up oxygen breaking down dead algae
Nutrients cause an algal bloom. When the algae die, aerobic decomposers multiply and their respiration removes oxygen from the water.
Q7 · Difficulty 3/3
Which strategy would reduce the volume of landfill waste most effectively in the long term?
- Burning all waste in the open
- Exporting waste to another country
- Digging deeper landfill sites
- Reducing packaging and reusing materials
Show answer & explanation
✓ Answer: D — Reducing packaging and reusing materials
Burning, exporting and deeper burial all move the problem rather than solve it. Reducing and reusing cut the waste at source, which is the only permanent reduction.
Q8 · Difficulty 3/3
A reef covers 2,400 hectares and loses 15% of its remaining area each decade. About how much is left after two decades, in hectares?
- 1680
- 2040
- 1734
- 1800
Show answer & explanation
✓ Answer: C — 1734
Award 1 mark. After one decade: 2,400 × 0.85 = 2,040 ha. After two: 2,040 × 0.85 = 1,734 ha. 1,680 wrongly takes 30% of the original area, ignoring that each loss is of the area remaining.
CXC CSEC Biology FAQ
What does the CXC CSEC Biology exam look like?
The CXC CSEC Biology 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 Biology 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 Biology 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.