Science 6 · Unit 3: Rocks, the rock cycle and soil · Cambridge Primary Science Stage 6

Questions

1. 1. What helps to make soil?

   • cooling magma only
   • melted metal
   • plastic
   • rocks broken up by weathering
   Check

2. 2. What is organic matter in soil?

   • air and water
   • sand and stones
   • plastic bits
   • living things or things that were alive, like dead leaves and roots
   Check

3. 3. What is soil texture?

   • the depth of soil
   • the smell of soil
   • the colour of soil
   • how the soil feels, e.g. rough, smooth or sticky
   Check

4. 4. Which soil has large particles and drains water easily?

   • loam
   • sandy soil
   • waterlogged soil
   • clay soil
   Check

5. 5. Which soil has very small particles and feels smooth and sticky?

   • sandy soil
   • gravel
   • clay soil
   • loam
   Check

6. 6. Why can clay soil become waterlogged?

   • It is made of sand.
   • It holds water and the water does not drain through.
   • It has huge air spaces.
   • It is always dry.
   Check

7. 7. What happens to clay soil in hot, dry weather?

   • It turns into loam.
   • It turns into sand.
   • It dries out and cracks.
   • It gets wetter.
   Check

8. 8. Why is loam the best soil for growing plants?

   • It has no air.
   • It is pure sand.
   • It is a mix of sand and clay with lots of organic matter.
   • It never holds water.
   Check

9. 9. What does a dark colour in soil show?

   • It is very dry.
   • It is very sandy.
   • It has no nutrients.
   • It contains lots of organic matter.
   Check

10. 10. Which soil is best for planting rice in water?

    • dry loam
    • clay soil
    • sandy soil
    • gravel
    Check

11. 11. Shale weathers into which type of soil?

    • loam only
    • sandy soil
    • clay soil
    • no soil
    Check

12. 12. Why do farmers dig or plough the soil?

    • to make it waterlogged
    • to mix air into the soil
    • to remove all organic matter
    • to add plastic
    Check

13. 13. What is compost made from?

    • artificial fertilisers
    • plastic bottles
    • sand and stones
    • dead organic matter like food scraps and garden waste
    Check

14. 14. How is compost better than artificial fertiliser?

    • It also improves the texture of the soil.
    • It kills organic matter.
    • It dries out the soil.
    • It has no nutrients.
    Check

15. 15. How does planting the same crop every year damage soil?

    • It makes too much compost.
    • It makes the soil darker.
    • It adds too much air.
    • The crop uses up the nutrients.
    Check

16. 16. What is biological pest control?

    • adding fertiliser
    • spraying pesticides
    • using natural predators, like ladybirds, to eat pests
    • ploughing twice
    Check

17. 17. How do organic farmers keep their soil healthy?

    • They use lots of pesticides.
    • They rotate crops and use compost.
    • They never dig the soil.
    • They plant the same crop always.
    Check