2015 HCI H2 Biology Prelims Paper 1 Questions

HWA CHONG INSTITUTION JC2 Preliminary Examinations Higher 2 CANDIDATE NAME CT GROUP 14S ___ CENTRE NUMBER INDEX NUMBER BIOLOGY Paper 1 Multiple Choice Additional Materials: Optical Mark Sheet 9648 / 01 17 September 2015 1 hour 15 minutes INSTRUCTIONS TO CANDIDATES 1. Write your name, CT group, Centre number and index number in the spaces provided at the top of this cover page. 2. Fill in your particulars on the Optical Mark Sheet. Write your NRIC number and shade accordingly. 3. There are forty 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 record your choice in soft pencil on the separate Optical Mark Sheet. 4. At the end of the paper, you are to submit only the Optical Mark Sheet. INFORMATION FOR CANDIDATES 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 31 printed pages and 1 blank page.

2 © Hwa Chong Institution 2015 9648 H2 Biology / JC2 Preliminary Exams / Paper 1 1 The following electron micrographs show various organelles P to T present in a liver cell. Radioactive amino acids are supplied to the liver cell to synthesise insulin receptors. Which sequence shows the correct order in which these amino acids would be detected in the organelles during the synthesis of insulin receptors? A Q  T  R  P  S B Q  T  P  S C T  P  S  R D T  S  P P R S T Q

3 © Hwa Chong Institution 2015 9648 H2 Biology / JC2 Preliminary Exams / Paper 1 2 Chromatography is a technique used to separate molecules by their solubility. The diagram shows an apparatus used for this technique. As the solvent rises up the paper, the molecule s with the greatest solubility in the solvent travel the greatest distances up the paper. When the solvent reaches the top of the paper, the paper is removed, dried and sprayed with a dye. The different molecules appear as coloured spots. Chromatography was carried out on four different samples – sucrose, cellulose as well as the products of complete hydrolysis of sucrose and cellulose. The diagram shows the chromatography results: Which row shows the correct results? sucrose cellulose products of complete hydrolysis of sucrose products of complete hydrolysis of cellulose A 4 3 1 2 B 3 4 2 1 C 1 2 3 4 D 2 1 4 3 absorbent paper solvent a mixture containing one or more types of molecules 1 2 3 4

4 © Hwa Chong Institution 2015 9648 H2 Biology / JC2 Preliminary Exams / Paper 1 3 The rate of reaction of a typical human enzyme was compared with the rate of reaction of a typical enzyme taken from bacteria that live in hot springs. The rates of reaction were measured over the same range of temperatures. The data obtained is shown in the following diagram. Which statement can be concluded? A Typical human enzymes fail to act at temperatures above 50 ºC as they are denatured due to disruption of covalent bonds. B The temperature coefficient for typical enzymes from bacter ia that live in hot springs is two for temperatures between 45ºC to 75ºC. C A denatured human enzyme would resume activity if reincubated at 20ºC. D Enzymes from bacteria that live in hot springs withstand temperatures up to 90 ºC as they have a low Km value. 4 A group of diploid cells with x amount of DNA and 36 chromosomes each is capable of undergoing mitosis and meiosis. During which stage(s) could a cell with 2x amount of DNA and 72 chromosomes be found? A anaphase of mitosis only B anaphase of meiosis I only C anaphase of mitosis and anaphase of meiosis I D anaphase of mitosis and anaphase of meiosis II temperature / ºC rate of reaction / arbitrary units human bacteria 100 80 60 40 20 0

5 © Hwa Chong Institution 2015 9648 H2 Biology / JC2 Preliminary Exams / Paper 1 5 The graph shows measurements during one mitotic cell cycle. What is the behaviour of chromosomes from X onwards as illustrated by curves 1 and 2? behaviour of chromosomes curve 1 curve 2 A separation of sister chromatids distance between the centromeres of sister chromatids distance between centromeres of chromosomes and poles of spindle B separation of sister chromatids distance between centromeres of chromosomes and poles of spindle distance between the centromeres of sister chromatids C separation of homologous chromosomes distance between centromeres of chromosomes and poles of spindle distance between the centromeres of homologous chromosomes D separation of homologous chromosomes distance between the centromeres of homologous chromosomes distance between centromeres of chromosomes and poles of spindle time / min distance / µm X 1 2

6 © Hwa Chong Institution 2015 9648 H2 Biology / JC2 Preliminary Exams / Paper 1 6 The diagram shows some of the events that take place during meiosis. 1 2 3 4 5 6 Which sequence of events is correct? A 6  5  3  2  4  1 B 6  3  5  4  2  1 C 3  2  6  4  1  5 D 3  6  2  4  5  1

7 © Hwa Chong Institution 2015 9648 H2 Biology / JC2 Preliminary Exams / Paper 1 7 Samples of DNA were taken from four individuals and processed as shown in the flowchart. original samples DNA sample 1 DNA sample 2 DNA sample 3 DNA sample 4 step X – separation of the DNA strands in samples 1 to 4 samples after step X DNA sample 1 DNA sample 2 DNA sample 3 DNA sample 4 step Y – mixing of some samples and treatment of mixed samples mixture of samples DNA samples 1 and 2 DNA samples 1 and 3 DNA samples 3 and 4 Which conclusion is correct? A Samples 1 and 2 are from individuals belonging to the same species. B Treatment at step X included cooling each of the original samples. C Treatment of mixed samples at step Y included the addition of DNA helicase. D Individuals belonging to samples 1 and 3 are more closely related than individuals belonging to samples 3 and 4.

8 © Hwa Chong Institution 2015 9648 H2 Biology / JC2 Preliminary Exams / Paper 1 8 Which statement(s) about RNA is / are correct? 1 It is less stable than DNA as it contains a ribose sugar that lacks a 2’ OH group. 2 It is able to form double-stranded regions with some areas of base pairing. 3 It is a polymer of purine and pyrimidine joined by phosphodiester bonds. 4 It is synthesised in the 5’ to 3’ direction where the 5’ -phosphate group of the growing RNA strand is joined to the 3’-hydroxyl group of an incoming nucleotide. A 2 B 1 and 4 C 2 and 3 D 1, 3 and 4 9 The diagram outlines the production of protein in a cell. Which statements are correct? 1 DNA involved has the base sequence TACGGCCTTCTGCCTGGGGGACTAACT. 2 RNA polymerase is active during step P and removal of exons by spliceosome occurs at step Q to give product R. 3 Bond T is synthesised by RNA found in structure S. 4 The mRNA shown will code for a protein containing eight amino acids. A 1 and 4 B 3 and 4 C 1, 2 and 3 D 1, 3 and 4 step P step Q product R structure S bond T nuclear membrane

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