CJC 2023 JC2 Bio P3 (ans)

NAME: ___________________________________________ CLASS: _________ INDEX: __________ CATHOLIC JUNIOR COLLEGE JC2 PRELIMINARY EXAMINATION Higher 2 BIOLOGY 9744/03 Paper 3 Long Structured and Free-Response Questions 13 September 2023 2 Hours Candidates answer on the Question Paper. Additional Material: Writing Booklet. READ THESE INSTRUCTIONS FIRST Write your name (as per NRIC), class, and index number on all the work you hand in. Write in dark blue or black pen on both sides of the paper. [PILOT FRIXION ERASABLE PENS ARE NOT ALLOWED] You may use a soft pencil for any diagrams, graphs, or rough working. Do not use staples, paper clips, highlighters, glue, or correction fluid. Section A Answer all questions in the spaces provided on the Question Paper. Section B Answer any one question in this section. Write your answers in the writing booklet provided. 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 not use appropriate units. The number of marks is given in brackets [ ] at the end of each question or part question. This document consists of 21 printed pages and 0 blank page. [ T u r n o v e r For Examiner’s Use Section A 50 1 2 3 Section B 25 4 or 5 Total 75 Suggested Answers

2 2023 Prelim/ 9744/ 03 Section A Answer all the questions in this section. 1 Endosymbiont is a cell which lives inside another cell with mutual benefit. The organelle in Fig. 1.1 is believed to have evolv ed from the early prokaryote that was engulfed by phagocytosis. The engulfed prokaryotic cell remained undigested as it contributed new functionality to the engulfing cell. Over generations, the engulfed prokaryotic cell lost some of its independent utility and became a supplemental organelle. Fig 1.1 (a) Explain how the organelle shown above supports the endosymbiotic theory. …………………………………………………………… ………………………………………………...... …………………………………………………………… ………………………………………………...... …………………………………………………………… ………………………………………………...... …………………………………………………………… ………………………………………………. [2] 1. Circular DNA, which is different from nuclear linear DNA. 2. 70s ribosome as compared to 80s ribosome. 3. Double membrane structure, the outer membrane was part of the host cell. (b) Explain how the organelle is adapted to its function. …………………………………………………………… ………………………………………………...... …………………………………………………………… ………………………………………………...... …………………………………………………………… ………………………………………………...... …………………………………………………………… ………………………………………………...... …………………………………………………………… ………………………………………………...... …………………………………………………………… ………………………………………………. [3]

3 2023 Prelim/ 9744/ 03