SAJC 2023 H2 BIO P1 QP

Civics Group Index Number Name (use BLOCK LETTERS) ST. ANDREW’S JUNIOR COLLEGE 2023 JC2 PRELIMINARY EXAMINATIONS H2 BIOLOGY 9744/01 Paper 1: Multiple Choice Monday 18th September 2023 1 hour Additional Materials: Multiple Choice Answer Sheet (OTAS) READ THESE INSTRUCTIONS FIRST Do not open this booklet until you are told to do so. Write your name, civics group and index number on the multiple choice answer sheet in the spaces provided. There are 30 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 multiple choice Optical answer sheet. INFORMATION TO CANDIDATES Each correct answer will score one mark. A mark will not be deducted for wrong answer. Any rough working should be done in this booklet. At the end of the examination, submit both question paper and multiple choice answer sheet. This document consists of 22 printed pages [Turn over] H2

2 SAJC / H2 Biology 9744/1 JC2 Prelim 2023 Answer all questions 1 A new fossil unicellular organism was discovered in rocks 150 million years old. Scientists studied the cell structure of several samples under the electron microscope. Which features suggest it was a eukaryote and not a prokaryote? 1 The nucleus was enclosed by a nuclear envelope with nuclear pores and contained two nucleoli. 2 The cisternae of rough endoplasmic reticulum were covered with ribosomes. 3 Oval organelles 1-2 μm long, in which the inner membrane was folded. 4 The cell wall was an extracellular structure, oval in shape. A 1 and 2 only B 1 and 4 only C 1, 2 and 3 only D 2 and 3 only 2 The following are a series of organic molecules and the chemical processes that occur to convert them into different molecules. Which of the rows, A to D, is correct?

3 SAJC / H2 Biology 9744/1 JC2 Prelim 2023 3 The graphs show the rate of uptake of sugars by a culture of animal cells, under different conditions. How are the sugars taken up by the cells when air is bubbled through the culture? 3-carbon sugar 6-carbon sugar A active transport active transport B active transport diffusion C diffusion active transport D diffusion diffusion

4 SAJC / H2 Biology 9744/1 JC2 Prelim 2023 4 The figure shows the metabolic pathways leading to synthesis of five amino acids: aspartate, lysine, methionine, threonine and isoleucine. E1 to E8 represent different enzymes involved in these pathways. Which of the options is an example of end-product inhibition? A aspartate inhibits E3 and E4 B lysine inhibits E1 and E6 C isoleucine inhibits E7 D methionine inhibits E8

5 SAJC / H2 Biology 9744/1 JC2 Prelim 2023 5 Down’s syndrome can be caused by a triso