2026 TJC JC2 Prelim H2 Biology P1 (Ans)

1 [Turn over TEMASEK JUNIOR COLLEGE 2026 JC2 PRELIMINARY EXAMINATION Higher 2 ANSWERS BIOLOGY 9477/01 Paper 1 Multiple Choice 17 September 2026 1 hour Additional Materials: Multiple Choice Answer Sheet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, glue or correction fluid. Write your name, civics group and index number on the Answer Sheet in the spaces provided. Do not open this booklet until you are told to do so. There are thirty questions on 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 Answer Sheet. Read the instructions on the Answer Sheet very carefully. 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 23 printed pages and 1 blank pages.

2 1 Cell membranes in three different organisms adapted for different climates are shown below. Several regions of the world are known to have the following climates: • desert region is hot and dry • tropical region is warm and wet • temperate region is cool and moderate • arctic region is cold and dry Which of the following correctly matches the regions to each type of cell membrane? 1 2 3 A desert arctic temperate B arctic desert tropical C desert temperate arctic D tropical arctic desert 1 2 3 1 2 3

3 [Turn over 2 The photomicrograph shows part of a cell. Which row is correct? this cell contains 70s ribosomes this could be part of a plant cell the organelles shown could be used to make antibodies A    B    C    D    key  = correct  = not correct The answer is supposed to be A Double checked CIE 9700 N25/qp11

4 3 The diagram shows how nicotine is transported from blood plasma into a cell using a type of cotransporter mechanism. With reference to the figure above, which statement best describes the transport of nicotine? A The cotransporter protein generates a proton gradient by moving protons out of the cell by active transport. B The protons are transported through the cotransporter protein by facilitated diffusion. C The cotransporter protein uses the energy stored in the proton gradient to drive the movement of nicotine. D The cotransporter protein uses energy from ATP to transport protons with nicotine. 4 When the enzyme starch synthase has made a chain of more than 11 α-glucose units, a second enzyme, enzyme X, transfers about 7 units from the end of this 1,4 -linked chain to carbon 6 of a unit in the remaining part of the chain. In what ways is starch better suited to its role by the action of enzyme X? 1 The molecule is less soluble. 2 The molecule is more compact. 3 The osmotic effect of the molecule is reduced. 4 Break down of the molecule or further addition of glucose is quicker. A 1, 2, 3 and 4 B 1, 2 and 4 C 2 and 4 D 3 and 4 blood plasma protons move down their concentration gradient out of the cell cell surface membrane cytoplasm of the cell nicotine is transported against its concentration gradient into the cell cotransporter protein

5 [Turn over 5 In a healthy human, the mean value for the number of haemoglobin molecules in one red blood cell is 260 million . How many β-globin chains does one red blood cell contain in a healthy human? A 1.3 × 108 B 2.6 × 108 C 5.2 × 108 D 1.04 × 109 6 In beer -making, enzymes present in malting barley hydrolyse starch into sugar, ready for fermentation. The graph shows the production of sugar at three different temperatures over a period of 50 minutes. All other variables were kept constant. Which of these statements can be concluded from the results? 1 At 60°C, all starch is hydrolysed within 30 min. 2 At 70°C, the enzymes are denatured before hydrolysis is complete. 3 Sugar concentration remains at 10 a.u. until 5 min. 4 The optimum temperature for the enzymes is 50°C. A 1, 2 and 4 B 2 and 4 C 1 and 3 D 2 only sugar concentration/ a.u. 10 20 30 40 0 10 20 30 40 50 time/ min 60°C 70°C 50°C

6 7 A student carried out an experiment to investigate the effect of pH on an enzyme- catalysed reaction. The optimum condition for this enzyme is the acidic environment of the stomach at pH 1 to 2. After five minutes, the remaining substrate concentration was measured for each pH from pH 1 to 8. Which graph shows the effect of increasing pH on substrate concentration remaining after five minutes? A B C D substrate concentration remaining after 5 min substrate concentration remaining after 5 min substrate concentration remaining after 5 min substrate concentration remaining after 5 min 1 pH 2 3 4 5 6 7 8 1 pH 2 3 4 5 6 7 8 1 pH 2 3 4 5 6 7 8 1 pH 2 3 4 5 6 7 8

7 [Turn over 8 The diagram below shows a section through a part of a mitochondrion. Which letters correctly represent the locations of the processes? glycolysis Krebs cycle electron transport chain A R S T B U T R C R U T D T R S 9 The statements below relate to Calvin cycle. Which of the following statement(s) is/are correct? 1 Molecules of triose phosphate are required for the synthesis of nucleic acids. 2 The production of triose phosphate from glycerate -3-phosphate requires ATP and reduced NAD. 3 Reactions of the Calvin cycle occurs at a faster rate when stomata are closed. A 1, 2 and 3 B 1 and 2 C 2 and 3 D 1 only

8 10 The photomicrograph shows a stage of the cell cycle. Which stage is shown in the photomicrograph? A anaphase B interphase C metaphase D telophase 11 The following experiment was carried out. 1 Haploid cells, containing three chromosomes each, were grown in a medium containing radioactive thymine, so that all DNA was labelled. 2 Cells in early interphase were then transferred to a medium where the available thymine was not radioactive. 3 A single cell was immediately isolated and allowed to divide once. When the two daughter cells reached the next metaphase, they were fixed and their three chromosomes were inspected for radioactivity. Which diagram represents the distribution of radioactivity at metaphase in the two daughter cells? A B C D key radioactive chromatid daughter cell 1 daughter cell 2 normal chromatid

9 [Turn over 12 Stem cells are found in many tissues that require frequent cell replacement such as the skin, the intestine and the blood. However, within their own environments, a blood cell cannot be induced to produce a skin cell and a skin cell cannot be induced to produce a blood cell. Which statement explains this? A Different stem cells have only the genes required for their particular cell line. B Genes not required for the differentiation of a particular cell line are methylated. C Binding of repressor molecules prevents the expression of genes not required for a particular cell line. D Expression of genes not required for a particular cell line is controlled at translational level. 13 Which statements correctly describe features of stem cells that are essential for their role in cell replacement and tissue repair? 1 After mitosis of stem cells, the daughter cells can either remain as stem cells or follow a developmental pathway that leads to the formation of specialised cells. 2 Stem cells are different to all other body cells because they retain all of the genetic informatio