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02107032/CAPE/SPEC/KMS 2017

BIOLOGY

UNIT 1 -- PAPER 032
MARK SCHEME

Question 1. (continued) UK XS

(d) (ii)  Solution 0.5M has a lower potential than the
cortical cell sap.
 Water moves by osmosis from the cortical cells into
the bathing solution.
 The cell vacuole is reduced in volume.
 The tissue becomes flaccid and draws the inelastic
epidermis inwards.
3 correct points -- 2 marks 2
2 correct points -- 1 mark
1 correct point -- 0 marks

(e) The cortical parenchyma cells are turgid.
They are compressed under restraint of the inflexible 1
epidermis.
When released from constraint, they expand.

Correct concept -- 1 mark

Total 18 marks 6 12

Syllabus Objectives: 3.2, 3.3 -- Module 1