2025 NYJC H2 Bio 9744 P2 MS

9744 / H2 Biology / 02 NANYANG JUNIOR COLLEGE JC 2 PRELIMINARY EXAMINATION Higher 2 CANDIDATE NAME CLASS BIOLOGY 9744/02 Paper 2 Structured Questions 15 September 2025 Candidates answer on the Question Paper. No Additional Materials are required. 2 hours READ THESE INSTRUCTIONS FIRST Write your name and CT on all the work you hand in. Write in dark blue or black pen. You may use an HB pencil for any diagrams or graphs. Do no use staples, paper clips, highlighters, glue or correction fluid. DO NOT WRITE IN ANY BARCODES. 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 no use appropriate units. At the end of the examination, fasten all your work securely together. The number of marks is given in brackets [ ] at the end of each question or part question. For Examiner’s Use 1 10 2 8 3 10 4 10 5 11 6 10 7 10 8 10 9 10 10 6 11 5 Total 100 This document consists of 27 printed pages and 2 blank pages. [Turn over H

9744 / H2 Biology / 02 2 Answer all the questions in this section. 1 In the majority of cell types, ribosomes are the most common organelle. They are found in the cytoplasm of bacterial and eukaryotic cells. [2024 H1 A Levels] (a) (i) List the two types of biomolecule that are found in ribosomes. Protein, ribosomal RNA /ribonucleic acid [1] (ii) State one difference between the ribosomes found in the cytoplasm of bacteria and the ribosomes found in the cytoplasm of eukaryotes. Bacteria have 70s ribosomes whereas eukaryotes have 80s ribosomes. [1] (iii) State two differences, other than differences in ribosomes, between typical bacterial cells and typical eukaryotic cells. 1. Bacterial cells have peptidoglycan cell wall whereas eukaryotes have cellulose cell wall. 2. Bacterial cells have circular DNA whereas eukaryotic DNA is linear 3. Bacterial cells lack nucleus/membrane bound organelles whereas eukaryotes have. [2] (b) Scientists have estimated the numbers of ribosomes found in cells. Fig. 1.1 is an electronmicrograph showing ribosomes in a cell. x67700 Fig. 1.1

9744 / H2 Biology / 02 3 (i) Suggest why it is difficult to use electronmicrographs, such as that shown in Fig. 1.1, to determine the total number of ribosomes in a cell. 1. Too many ribosomes to count which may cause inaccuracy in counting 2. Difficult to distinguish individual ribosomes as some are clustered together 3. Limited field of view capturing a small section of the cell, which may not be a good representation of the ribosome density of the entire cell. [3] (ii) Fig. 1.2 shows data for the number of ribosomes present in cells of different vol