2017 HCI H2 Biology Prelims Paper 3 Questions

© Hwa Chong Institution 2017 9744 H2 Biology / JC2 Preliminary Examinations / Paper 3 HWA CHONG INSTITUTION JC2 Preliminary Examinations Higher 2 CANDIDATE NAME CT GROUP 16S7 ___ CENTRE NUMBER INDEX NUMBER BIOLOGY Paper 3 Long Structured and Free-response Questions No Additional Materials are required. 9744/03 13 September 2017 2 hours INSTRUCTIONS TO CANDIDATES There are four question booklets (I to IV) 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 your name and CT group on the lines provided at the top of the cover page of Booklets II, III and IV. SECTION A This section contains three structured questions. Answer all parts in the spaces provided on the question paper. SECTION B This section contains two free-response questions. Answer any one question. Your answer must be in continuous prose, where appropriate. 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 English and clear presentation in your answers. This document consists of 19 printed pages and 5 blank pages. For Examiners' Use 1 / 25 2 / 10 3 / 15 4 or 5 / 25 Final Mark / 75

2 © Hwa Chong Institution 2017 9744 H2 Biology / JC2 Preliminary Examinations / Paper 3 BOOKLET I SECTION A QUESTION 1 Plants harvest light energy from the sun for photosynthesis, producing biomass that is used as food. Such biomass can also be used as ‘biofuels’, which include wood, ethanol, biodiesel and biogas. Biofuels offer plant-based solutions to the Earth's growing energy problems. Oats and wheat, commonly grown in temperate regions, are C3 plants. Most plants are C3 plants and are so-called because their first photosynthetic product is a three carbon compound. Corn, sorghum and sugarcane are C4 plants. They are common food crops of tropical regions. The enzyme ribulose bisphosphate carboxylase oxygenase (rubisco) catalyses the fixation of carbon dioxide in the Calvin cycle and is used by both C3 and C4 plants. Each molecule of rubisco is made up of eight large polypeptides and eight small polypeptides. Fig. 1.1 shows a side view of the molecule. Fig. 1.1 (a) (i) State why rubisco is said to have quaternary structure. [1] (a)(ii) Explain what makes a molecule such as rubisco soluble. [2] small polypeptide large polypeptide

3 © Hwa Chong Institution 2017 9744 H2 Biology / JC2 Preliminary Exam