2017 HCI H2 Biology Prelims Paper 2 Questions

© Hwa Chong Institution 2017 9744 H2 Biology / JC2 Preliminary Examinations / Paper 2 HWA CHONG INSTITUTION JC2 Preliminary Examinations Higher 2 CANDIDATE NAME CT GROUP 16S ___ CENTRE NUMBER INDEX NUMBER BIOLOGY Paper 2 Structured Questions No additional materials are required. 9744/02 23 August 2017 2 hours INSTRUCTIONS TO CANDIDATES There are six question booklets (I to VI) to this paper. Write your name, CT group, Centre number and index number in the spaces provided at the top of this cover page and on the lines provided at the top of the cover pages of Booklets II, III, IV, V and VI. This paper contains nine structured questions. Answer all questions in the spaces provided on the question paper. INFORMATION FOR CANDIDATES 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. You are reminded of the need for good Englis h and clear presentation in your answers. This document consists of 28 printed pages and 8 blank pages. For Examiners' Use 1 / 12 2 / 11 3 / 9 4 / 10 5 / 14 6 / 12 7 / 10 8 / 13 9 / 9 Total Mark / 100

2 © Hwa Chong Institution 2017 9744 H2 Biology / JC2 Preliminary Examinations / Paper 2 BOOKLET I QUESTION 1 The cell theory was developed in the 1830s. At the same time, it was proposed that living things arose spontaneously from non-living materials. This theory of “spontaneous generation” was later disproven, but the cell theory has stood the test of time to become widely accepted in the scientific community today. (a) Outline the cell theory. [2] Fig. 1.1 shows Louis Pasteur’s famous swan neck flask experiment that disproved the spontaneous generation theory and supported the cell theory. Fig. 1.1 (b)(i) With reference to Fig. 1.1, explain how Pasteur’s experiment supports the cell theory. [2] Short time Long time Liquid remains microbe-free indefinitely Microorganisms grow in liquid Microorganisms trapped in bend Flask remains upright Flask tipped so that microorganisms contact sterile liquid Steam forced out open end Liquid sterilised by extensive heating Non-sterile liquid (nutrient broth) poured into flask

3 © Hwa Chong Institution 2017 9744 H2 Biology / JC2 Preliminary Examinations / Paper 2 (a)(ii) Suggest a reason for the universal acceptance of the cell theory in our world today. [1] Pseudomonas syringae is a pathogen that can enter plants through wounds and cause disease in a wide variety of pl