2016 HCI H1 Biology Prelims P2 Questions

HWA CHONG INSTITUTION JC2 Preliminary Examination Higher 1 CANDIDATE NAME CT GROUP 15S ___ CENTRE NUMBER INDEX NUMBER BIOLOGY 8875 / 02 Paper 2 Core Paper 13 September 2016 Additional Materials: Writing Paper 2 hours INSTRUCTIONS TO CANDIDATES Write your name and CT group in the spaces provided at the top of this cover page. SECTION A This section contains four questions. Answer ALL questions. Write your answers on the lines / in the spaces provided. SECTION B This section contains two questions. Answer any one question. Your answers must be in continuous prose, where appropriate. Write your answers on the writing paper provided. BEGIN EACH PART ON A FRESH SHEET OF WRITING PAPER. A NIL RETURN is required for questions not answered. INFORMATION FOR CANDIDATES The number of marks is given in brackets [ ] at the end of each question or question part. The use of an appropriate scientific calculator is expected, where appropriate. You may lose marks if you do not show working or if you do not use appropriate units. You are reminded of the need for good English and clear presentation in your answers. This document consists of 12 printed pages. For Examiners' Use Question Marks 1 / 9 2 / 8 3 / 9 4 / 14 5 / 6 / 20 Total / 60

2 © Hwa Chong Institution 2016 8875 H1 Biology / Preliminary Exam / Paper 2 SECTION A: STRUCTURED QUESTIONS QUESTION 1 (a) Explain the role of helicase in DNA replication. [2] Cytarabine is a drug used to treat certain cancers. It prevents DNA replication. Fig. 1.1 shows the structures of cytarabine and the DNA base cytosine. Fig. 1.1 (b) Explain how cytarabine prevents DNA replication. [2] cytarabine cytosine

3 © Hwa Chong Institution 2016 8875 H1 Biology / Preliminary Exam / Paper 2 Fig. 1.2 shows information about the movement of chromatids in a cell that has just started metaphase of mitosis. Fig. 1.2 With reference to Fig. 1.2, (c) (i) state the duration of metaphase in the cell. [1] (ii) complete line Y on the graph. [1] distance between chromatids distance between each chromatid and the pole to which it is moving distance / µm key time after start of metaphase / minutes start of metaphase

4 © Hwa Chong Institution 2016 8875 H1 Biology / Preliminary Exam / Paper 2 (iii) account for your answer in (c)(ii). [3] [Total: 9]

5 © Hwa Chong Institution 2016 8875 H1 Biology / Preliminary Exam / Paper 2 QUESTION 2 The unicellular green alga, Chlorella, a photosynthetic eukaryote