RI 2023 Prelim H2 Bio P1 QP

© RI 2023 Preliminary Examination 9744/01 [Turn over RAFFLES INSTITUTION 2023 Year 6 Preliminary Exam Higher 2 BIOLOGY 9744/01 Paper 1 Multiple Choice 28th Sept 2023 1 hour Additional Materials: Multiple Choice Answer Sheet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. Write your name and shade your Index Number on the Answer Sheet in the spaces provided unless this has been done for you. There are thirty questions in this paper. Answer al l questions. For each question there are four possible answers A, B, C, and D. Choose the one you consider correct and record your choice in soft pencil on the separate Answer Sheet. Read the instructions on the Answer Sheet very carefully. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Any rough working should be done in this booklet. The use of an approved scientific calculator is expected, where appropriate. (Erase all mistakes completely. Do not bend or fold the OMR Answer Sheet). This document consists of 21 printed pages. Raffles Institution Internal Examination

2 © RI 2023 Preliminary Examination 9744/01 1. The diagrams below show the results of an investigation into the composition of different mixtures of amino acids. Each mixture of amino acids was separated using chromatography. Each chromatogram was then turned 90 o and the amino acids were separated again by electrophoresis. Which diagram shows an amino acid mixture in which the solubility of some of the amino acids is the same but the charge on those particular amino acids is different? A B C D

3 © RI 2023 Preliminary Examination 9744/01 [Turn over 2. The enzyme invertase catalyses the breakdown of sucrose to glucose and fructose. Three different enzyme inhibitors of invertase, X, Y and Z were investigated. The percentage inhibition of invertase was measured at different concentrations of inhibitor. The graph shows the results of the investigation. What are valid conclusions based on the above results? 1 The higher the concentration of inhibitor X, the less sucrose is broken down. 2 The production of glucose and fructose when using inhibitor Y is higher than when using inhibitor Z. 3 The production of glucose and fructose at an inhibitor concentration of 2 arbitrary units is lower than at an inhibitor concentration of 4 arbitrary units, for all inhibitors. 4 X is the most effective inhibitor. A 4 only B 1 and 4 only C 2 and 3