CJC 2023 JC2 Bio P1 (ans)

NAME: ___________________________________________ CLASS: _________ INDEX: __________ CATHOLIC JUNIOR COLLEGE JC2 PRELIMINARY EXAMINATION Higher 2 BIOLOGY 9744/01 Paper 1 Multiple Choice 18 September 2023 1 hour Additional Materials: Answer Sheet (Multiple Choice Optical Mark Sheet) READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. Write your name (as per NRIC), class, and index number on this booklet. Write and shade your name (as per NRIC) , NRIC / FIN number and class on the Answer Sheet (Multiple Choice Optical Mark Sheet) in the spaces provided. There are 30 multiple choice questions in this paper. Answer all questions. For each question, there are four possible answers, A, B, C and D. Choose the one you consider correct and shade your choice in soft pencil on the Answer Sheet (Multiple Choice Optical Mark 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. This document consists of 22 printed pages and 0 blank page [Turn over Suggested Answers

2   2023 Prelim/ 9744/ 01 1 The diagram shows two electron micrographs of cells. F G Which organelles are visible in each of the cells F and G? Key:  = visible  = not visible Answer: B cell chloroplasts nucleolus nucleus A F G       B F G       C F G       D F G      

3   2023 Prelim/ 9744/ 01 2 The figure below shows an electr on micrograph of a pair of barrel- shaped centrioles that play an important role in organising microtubules that serve as the cell’s skeletal system. They help determine the locations of the nucleus and other organelles within the cell. Microtubules are assembled from a heterodimeric protein called tubulin, as shown in the diagram below. Which of the following explains why tubulin is considered a polymer as well as a monomer? why tubulin is a polymer why tubulin is a monomer A It is a macromolecule. It is a quaternary protein. B It is the building block of microtubule. It is made up of many amino acids. C It is made up of many amino acids. It is the building block of microtubule. D It has many α-helices and β-pleated sheets. It is made up of two different subunits. Answer: C microtubule  α‐tubulin  β‐tubulin