TMJC 2023 H2 P1 QP

CANDIDATE NAME ( ) CIVICS GROUP H2 BIOLOGY 9744/01 Paper 1 Multiple Choice Questions 22 September 2023 1 hour Additional material: Multiple Choice Answer Sheet READ THESE INSTRUCTIONS FIRST Do not open this booklet until you are told to do so. Write your name, civics group and index number on the Multiple Choice Answer Sheet. Do not use staples, paper clips, glue or correction fluid/tape. There are 30 questions in this paper. Answer all questions. For each question, there are four possible answers labelled A, B, C and D. Choose the one you consider correct and record your choice in soft pencil on the separate Multiple Choice Answer Sheet. 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. You may keep this booklet after the exam. ________________________________________________________________________________ This document consists of 16 printed pages. TAMPINES MERIDIAN JUNIOR COLLEGE JC2 PRELIMINARY EXAMINATION

2 Tampines Meridian Junior College 2023 JC2 Preliminary Examination H2 Biology 1 The photomicrograph is of a plant cell. The cell is 25 µm in width from X to Y. What is the magnification of the photomicrograph? A 2 x 101 B 2 x 102 C 2 x 103 D 2 x 104

3 Tampines Meridian Junior College 2023 JC2 Preliminary Examination H2 Biology 2 The diagrams below show the electron micrographs of two organelles P and Q. Which of the following shows the correct identities and functions of P and Q? Identity of P Function of P Identity of Q Function of Q A Nucleosome Transcription of rRNA gene Smooth ER Transport of proteins B Nucleosome Assembly of ribosomal subunits Secretory vesicles Synthesis of lipids C Nucleolus Assembly of ribosomal subunits Smooth ER Synthesis of lipids D Nucleolus Transcription of rRNA gene Secretory vesicles Transport of proteins

4 Tampines Meridian Junior College 2023 JC2 Preliminary Examination H2 Biology 3 Which letter identifies the cell structures where semi-conservative replication of DNA occurs? 4 The chart shows the concentration of some substances outside the cell, in the cytoplasm, in the chloroplast and in the Golgi body of a plant cell. Which statement about the direction of movement of these substances and the process by which they are moving is correct? A ATP is leaving the chloroplast by facilitated diffusion, water is leaving the plant cell by osmosis. B Phosphate and ATP are entering the chloroplast and Golgi body by active transport. C Phosphate and ATP are leaving the Golgi body by facilitated diffusion, water is leaving the plant cell by osmosis. D Phosphate is entering the chloroplast by facilitated diffusion, water is entering the chloroplast by osmosis.

5 Tampines Meridian Junior College 2023 JC2 Preliminary Examination H2 Biology 5 The diagram shows some interactions between amino acid R-groups in a polypeptide chain. Which row correctly describes the nature of the interactions? can be disrupted by extreme pH can be disrupted by high temperatures located within the core of a globular protein located within the transmembrane domain of a receptor protein A 1, 3, 4 1, 2, 3, 4 2 1, 2, 4 B 2, 4 3 1, 4 2, 3 C 3 1, 4 2, 3 1, 2, 3, 4 D 1, 4 1, 4 2, 3 2 6 How many of the following statements correctly describe red blood cells? • At high altitude, humans have increased number of red blood cells to compensate for low percentage saturation of oxygen. • At high altitude, humans have increased number of red blood cells to increase the number of mitochondria in the blood for ATP production. • The shape of haemoglobin in red blood cells changes when oxygen is released from it. • Haemoglobin in red blood cells is insoluble in water because hydrophobic R groups are arranged around the outside of the molecule. A 1 B 2 C 3 D 4

6 Tampines Meridian Junior College 2023 JC2 Preliminary Examination H2 Biology 7 Collagen is a fibrous protein found in mammalian tendons. Which feature contributes to the great tensile strength of collagen? A A secondary structure with many hydrogen bonds firmly holding the α-helices. B A regularly folded tertiary structure held together with hydrogen bonds and ionic bonds. C A primary sequence with covalent bonds linking a variable sequence of amino acids. D A quaternary structure of triple heli x held together by hydrogen bonds between the three polypeptides. 8 The lock-and-key hypothesis and induced-fit hypothesis explain how an enzyme interacts with a substrate. Which of the following statements are true of both hypotheses? 1 An increase in substrate concentration will not increase the rate of formation of enz yme- substrate complexes. 2 Covalent bonds hold the substrate at the active site of the enzyme. 3 An enzyme undergoes a conformational change as it forms enzyme-substrate complexes. 4 An increase in enzyme concentration may increase the number of enzyme-substr ate complexes. A 4 only B 1 and 4 only C 1, 2 and 4 only D 1, 2, 3 and 4 9 The graph compares the effect of temperature on the activity of the protease enzyme, papain, when free in solution and when immobilised in alginate beads. Which statement about the effect of immobilisation of papain is correct? A It increases the stability of papain at higher temperatures. B It alters the shape of papain’s active site at 40 oC. C It decreases the activity of papain at 45oC. D It reduces the number of collisions of papain with the substrate.

7 Tampines Meridian Junior College 2023 JC2 Preliminary Examination H2 Biology 10 Rotenone and antimycin are two metabolic poisons which affect cellular respiration. The effects of rotenone and antimycin on aerobic respiration are summarised in the table. Ability to use glucose Ability to use oxygen ATP yield Rotenone Yes No Decreases Antimycin Yes Yes Decreases Which of the following correctly identifies the specific functions of these two metabolic poisons? 11 In an experiment, chloroplast extracts were first treated with a chemical that binds with the electron that was accepted by the electron acceptor in Photosystem I . The extracts were then treated with two hours of light and were provided with ample carbon dioxide and water. Which of the following correctly shows the products that were formed after the experiment? O 2 ATP Reduced NADP Glucose A + + - - B - + + + C + - - - D - - + - Rotenone Antimycin A Electron transport inhibitor Inhibits ATP synthase B Inhibits ATP synthase Electron transport inhibitor C Dissipate proton gradient Inhibits ATP synthase D Inhibits ATP synthase Dissipate proton gradient

8 Tampines Meridian Junior College 2023 JC2 Preliminary Examination H2 Biology 12 The diagram shows a few stages of respiration and number of carbon atoms in the compounds involved. Which reactions occur at Stages 1-3? Stage 1 Stage 2 Stage 3 A CO2