2024 NJC H2 Bio P2 MS

©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 sub-compartments. Name and state the role of structures A and B. name role A smooth endoplasmic reticulum; site of lipid synthesis; involved in drug detoxification; B rough endoplasmic reticulum (reject ribosomes on rough endoplasmic reticulum); involved in the synthesis of secretory proteins / membranal proteins; addition of carbohydrates to form glycoproteins / modifying of proteins; proteins synthesised are transported within vesicles to the Golgi body; [4] (b) Explain why it is important for a human liver cell to contain many glycogen granules. Serves as a form of energy storage (reject long-term/short-term if never specify comparison); Maintain blood glucose levels during times of high energy demands / stress / fasting;

4 ©NJC 2024 9744/02/SH2 Preliminar y Examination [2] 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. The isolation membrane expands to enclose the unwanted cytoplas m components such as mitochondrion; An autophagosome is formed after pore closure; Lysosome fuses with the autophagosome to form an autolysosome; Hydrolytic enzymes in the autolysosome catalyse the degradation of the inner membrane / the unwanted cytoplasm components; This proces