2025 NYJC H2 Bio 9744 P2 QP

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 2 3 4 5 6 7 8 9 10 11 Total 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. (a) (i) List the two types of biomolecule that are found in ribosomes. [1] (ii) State one difference between the ribosomes found in the cytoplasm of bacteria and the ribosomes found in the cytoplasm of eukaryotes. [1] (iii) State two differences, other than differences in ribosomes, between typical bacterial cells and typical eukaryotic cells. [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. [3] (ii) Fig. 1.2 shows data for the number of ribosomes present in cells of different volumes. Fig.1.2 Describe and explain the relationship shown in Fig. 1.2. [3] [Total: 10]

9744 / H2 Biology / 02 4 2 In 1953, James Watson and Francis Crick published details about the structure of DNA. They used experimental results from other scientists to help them work out the structure and then built a model of a section of a DNA molecule, using pieces of wire and met al, with clamp stands to hold the model in place. This is shown in Fig. 2.1. Fig. 2.1 (a) Watson and Crick used results from work carried out by Erwin Chargaff. He found that the proportions of the b