Question 20
Question 20 of 40
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Older MCQs might not have the typical A, B, C, D choices. They have choices 1, 2, 3, and a combination of them is the answer. Below is the key that maps such combinations to the answer.
A 1, 2 and 3 are correct
B 1 and 2 only are correct
C 2 and 3 only are correct
D 1 only is correct
Topics Tested
8. Transport in plants
8.1. Xylem and phloem

Relate the structure of xylem vessels to their function, limited to: (a) thick walls with lignin (details of lignification are not required) (b) no cell contents (c) cells joined end to end with no cross walls to form a long continuous tube

8. Transport in plants
8.3. Transpiration

Explain the mechanism by which water moves upwards in the xylem in terms of a transpiration pull that draws up a column of water molecules, held together by forces of attraction between water molecules