10 4 Transpiration moves water and mineral ions from the roots to the leaves of plants. (a) Which box in the table shows the mineral ions needed to make an amino acid and which box shows those needed to make DNA? (2) Molecule Mineral ions needed to make the molecule nitrate ions only phosphate ions only both nitrate and phosphate ions neither nitrate nor phosphate ions amino acid DNA (b) Water enters the root hair cells and moves through the root tissues by the apoplastic and symplastic pathways. (i) Root hairs have a large surface area that increases the rate of uptake of water. The surface area of a root hair is rounded up to 3.14 × 105 µm2. Which is the actual surface area of this root hair? (1) A 31 460 µm2 B 314 600 µm2 C 313 900 µm2 D 3 139 000 µm2 Turn over 11 (ii) Which row of the table shows the movement of water through the apoplastic and symplastic pathways? (1) Apoplastic pathway Symplastic pathway A B C D (iii) Water moves through the root tissue due to a difference in water potential between one cell and the next cell. Which row of the table describes this movement? (1) Direction of water movement with respect to water potential Direction of water movement with respect to concentration of solutions A higher to lower concentrated to dilute B higher to lower dilute to concentrated C lower to higher concentrated to dilute D lower to higher dilute to concentrated 12 (c) Explain how transpiration depends on the dipole nature of water. (3) ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................................................................... (Total for Question 4 = 8 marks)