VJC 2021 H2 Bio 9744 P4 QP

VICTORIA JUNIOR COLLEGE JC 2 PRELIMINARY EXAMINATION 2021 HIGHER 2 NAME : ……………………………………………………….………………. CT CLASS: ………………..……… BIOLOGY Paper 4 Practical 9744 / 04 02/09/2021 2 hours 30 minutes Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your name and CT in all the work handed in. Give details of the practical shift and laboratory, where appropriate, in the boxes provided. Write in dark blue or black pen. You may use an HB pencil for any diagrams or graphs. Do not use staples, paper clips, glue or correction fluid. Answer all questions in the spaces provided on the Question Paper. The use of an approved scientific calculator is expected, where appropriate. You may lose marks if you do not show your working or if you do not use appropriate units. At the end of the examination, fasten all your work securely together. The number of marks is given in bracket [ ] at the end of each question or part question. Shift Laboratory Question Marks 1 2 Total This document consists of 12 printed pages. [Turn over]

1 Answer all questions. 1 You should read through the whole of this question carefully before you start your investigation. Betalains are red pigments that are found in some fungi and flowering plants, including beetroot, Beta vulgaris. Betalains are glycosides consisting of a glucose molecule bound to a pigment compound by a glycosidic bond. Cells of B. vulgaris store molecules of betalain in their vacuoles. The membrane surrounding vacuoles in plant cells is the tonoplast, which has a similar structure to other cell membranes. (a) (i) Suggest why betalain molecules cannot pass from vacuoles of plant cells into the cytoplasm. …………............................................................................................................................................... …………............................................................................................................................................... …………............................................................................................................................................... …….................................................................................................................................................. [2] Various factors influence the permeability of membranes. You are required to investigate the effect of different concentrations of alcohol on the membrane permeability of root cells of B. vulgaris. You are provided with: • 3 cores of beetroot tissue in a beaker of distilled water • 100% alcohol • 10.0% betalain solution • 1.0% betalain solution • distilled water Alcohol is highly flammable and harmful. You are recommended to wear eye protection. Ensure that there is no naked flame. Proceed as fol