Sample answer A = Crust B = Mantle C = Asthenosphere
D = Lithosphere E = Outer core F = Inner core
12 marks × 2 marks = 6 names
(i) Describe briefly the main difference between the composition of layer C and layer D.
Understanding the question zz
zz
The command word is ‘Describe’: the examiner wants you to provide a detailed explanation of what, how or why something happens.
As this question needs to be developed, it requires a minimum of 2 SRPs worth 2 marks each.
Sample answer
Layer C is a part of the upper mantle composed of semi-molten rock called the asthenosphere. Layer D is the lithosphere, which consists of solid rock found in the upper mantle and outer crust.
(ii) Explain briefly why plates move.
Understanding the question zz
zz
4 marks × 2 marks = 2 SRPs
The command word is ‘Explain’: the examiner wants you to give reasons for how or why something happens.
As this question needs to be developed, it requires a minimum of 2 SRPs worth 2 marks each.
Sample answer
Tectonic plates float on heavier, semi-molten rock (magma) beneath them in the mantle They are moved along by convection currents in the molten rock, causing them to collide with, separate from and slide past each other.
Parts B and C are 30-mark questions that require short essay-style answers. Each answer requires 15 SRPs, with 2 marks awarded for each SRP. Marks will also be awarded for relevant named examples (2 marks each) and labelled diagrams (maximum of 4 marks). Parts B and C answers should take approximately 13 minutes.
