2024 NJC H2 Bio P2 QP

©NJC 2024 9744/02/SH2 Preliminary Examination [Turn over H NATIONAL JUNIOR COLLEGE, SINGAPORE Senior High 2 Preliminary Examination Higher 2 CANDIDATE NAME BIOLOGY CLASS 2bi2_____ R E G I S T R A T I O N NUMBER Biology Paper 2 Structured Questions Candidates answer on the Question Paper. No Additional Materials are required. 9744/02 27 August 2024 2 hours READ THESE INSTRUCTIONS FIRST Write your name, Biology class and registration number on all the work you hand in. Write in dark blue or black pen. You may use an HB 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 workings or if you do not use appropriate units. The number of marks is given in the brackets [ ] at the end of each question or part of question. For Examiner’s Use Section A 1 /10 2 /10 3 /10 4 /10 5 /10 6 /10 7 /10 8 /10 9 /10 10 /5 11 /5

2 ©NJC 2024 9744/02/SH2 Preliminar y Examination Total /100 This document consists of 26 printed pages and 2 blank pages.

3 ©NJC 2024 9744/02/SH2 Preliminary Examination [Turn over Answer all the questions. 1 Fig. 1.1 is an electronmicrograph of part of a human liver cell that contains many glycogen granules. Fig. 1.1 (a) Structures A and B are interconnected compartments. Name and state the role of structures A and B. name role A B [4] (b) Explain why it is important for a human liver cell to contain many glycogen granules. [2]

4 ©NJC 2024 9744/02/SH2 Preliminar y Examination Isolation membranes derived from structure A play important role in degradation of unwanted cytoplasm components. Fig. 1.2 shows the steps involved in the degradation of unwanted cytoplasm components. Fig. 1.2 (c) With reference to Fig. 1.2, describe how the unwanted cytoplasm components are degraded. [4] [Total: 10]

5 ©NJC 2024 9744/02/SH2 Preliminary Examination [Turn over 2 Fig. 2.1 shows the components of a storage molecule that is widely distributed in plants. A B Fig. 2.1 (a) Identify the components A and B. A B [2] (b) The presence of branches is a key structural feature of component A. Explain how this structural feature enables the function of component A. [2]

6 ©NJC 2024 9744/02/SH2 Preliminar y Examination Fig. 2.2 shows two types of glucose found in plants. Fig. 2.2 (c) With reference to Fig. 2.2, draw a labelled diagram in the spac e provided to show how two glucose molecules react to form a branch point in component A. [3] (d) Glycolipids are generally found on the extracellular face of eukaryotic cell surface membrane. Describe the roles of glycolipids in eukaryotic cell surface membrane. [3] [Total: 10]

7 ©NJC 2024 9744/02/SH2 Preliminary Examination [Turn over 3 (a) Fig. 3.1 shows the process of DNA replication. Fig. 3.1 ( i ) On Fig. 3.1, ● label a leading strand and a lagging strand ● draw an arrow to show the direction of movement of the replication fork. [3] ( i i ) Name the molecules A and B. A B [2] (iii) Describe how a mutation in the gene coding for molecule B can affect its function in DNA replication. [3]

8 ©NJC 2024 9744/02/SH2 Preliminar y Examination (b) Dideoxycytosine triphosphate (ddCTP) can bind to the active site of molecule B, in a similar way to deoxycytosine triphosphate (dCTP). Fig. 3.2 shows the structure of dCTP and ddCTP. Fig. 3.2 In an in vitro DNA replication reaction mixture, ddCTP was added together wit h deoxyribonucleotides. Suggest how the addition of ddCTP would affect DNA replication. [2] [Total: 10]

9 ©NJC 2024 9744/02/SH2 Preliminary Examination [Turn over 4 Epstein-Barr virus (EBV) was the first virus known to cause hum an cancer. Human B lymphocytes are the host cells of EBV infection. Fig. 4.1 shows the structure of EBV. Fig. 4.1 (a) (i) Identify the structures A and B. A B [2] ( i i ) List two differences between the EBV and influenza virus genomes. 1 2 [2] A B C double-stranded DNA

10 ©NJC 2024 9744/02/SH2 Preliminar y Examination Fig. 4.2 shows part of the reproductive cycle of EBV starting from its attachment to a B lymphocyte. Fig. 4.2 (b) (i) With reference to Fig. 4.2, describe two ways how EBV enters the B lymphocyte. [2]