2021 EJC Promo JC1 P1 Bio (Q)

©EJC 2021 9744/01/J1H2PROMO/2021 [Turn over EUNOIA JUNIOR COLLEGE JC1 Promotional Examinations 2021 General Certificate of Education Advanced Level Higher 2 H2 Biology Paper 1 Multiple Choice 9744/01 05 October 2021 1 hour Additional Materials: Multiple Choice Answer Sheet READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use paper clips, glue or correction tape/fluid. Write your name, civics group and registration number on the Answer Sheet in the spaces provided. There are thirty Multiple Choice 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 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 18 printed pages.

2 ©EJC 2021 9744/01/J1H2PROMO/2021 1 Raffinose is a trisaccharide which can be degraded by enzymes. The results of two different enzymatic incubations are shown here: enzyme used products sucrase melibiose and fructose galactosidase galactose and sucrose Which statements are consistent with the results shown above? 1 Raffinose is composed of two different monosaccharides. 2 Melibiose is a dissaccharide. 3 Acid hydrolysis of raffinose would yield glucose. 4 The products of raffinose digestion by sucrase and galactosidase will each yield an orange- red precipitate when heated with Benedict's reagent. A 1 and 3 only B 2 and 4 only C 2, 3 and 4 only D 1, 2, 3 and 4 2 In triglyceride molecules, where are carbon-carbon double bonds located? A between fatty acids and glycerol B within fatty acids and within glycerol C within fatty acids only D within glycerol only

3 ©EJC 2021 9744/01/J1H2PROMO/2021 [Turn over 3 Which correctly matches the functional and structural features of cellulose, collagen, glycogen and triglyceride? key: ✓= true ✗= false function structure fibrous molecule held together by hydrogen bonds branched chains A cellulose triglyceride support energy source   ✓    B collagen cellulose strengthening support       C collagen glycogen strengthening storage       D glycogen triglyceride storage energy source       4 Which row about the structure of proteins is correct? primary structure tertiary structure quaternary structure A is the number of amino acids present in a protein is the result of cross bonding between all the amino acids in the primary structure is the polypeptides that link together to form a protein B is the order of amino acids present in a protein encoded by DNA is the shape formed by folding of a polypeptide and held together by hydrogen bonds contains two types of polypeptide that interact forming the shape of a protein C is the result of translation of an mRNA molecule by a ribosome into a chain of amino acids is the result of ionic and hydrogen bonds, disulfide bridges and hydrophobic interactions between amino acids is formed by four polypeptides and an additional reactive group attached to the protein D is the sequence of amino acids in a protein coded by an mRNA molecule is formed as a result of interaction of the side chains of amino acids in the primary structure is formed by the linking together of more than one polypeptide to form a protein

4 ©EJC 2021 9744/01/J1H2PROMO/2021 5 During the development of HIV, the polyprotein is hydrolysed by a HIV protease enzyme, producing several smaller peptides. This viral enzyme is the target of new anti-AIDS drugs. Which feature is essential for the success of these drugs? A A complex structure that inhibits many types of viral and non-viral enzymes. B A molecule containing a heavy metal atom that is a non-competitive inhibitor of enzymes. C A protein that can act as a competitive inhibitor of protease enzymes. D A specific structure that inhibits only HIV protease. 6 The graphs show how the concentration of different components of an enzyme-catalysed reaction (e.g. substrate, active sites) changes with time. Which graph represents enzymes with empty active sites?

5 ©EJC 2021 9744/01/J1H2PROMO/2021 [Turn over 7 The diagram shows a stage micrometer scale viewed through an eyepiece containing a graticule. Each small division of the stage micrometer scale is 0.1 mm. The stage micrometer scale is replaced by a slide of a plant cell. What is the actual length of the nucleus in the plant cell? A 8 µm B 25 µm C 200 µm D 0.8 mm

6 ©EJC 2021 9744/01/J1H2PROMO/2021 8 The electron micrograph shows a cell structure in a eukaryotic cell. Which statement(s) about this cell structure is/are correct? 1 ATP is synthesised in this cell structure. 2 The cell structure is made of protein molecules. 3 The cell structure replicates during interphase of the cell cycle. A 3 only B 1 and 2 only C 1 and 3 only D 2 and 3 only 9 Which description of cell surface membrane permeability is correct? A An increase in the concentration of cholesterol molecules in the cell surface membrane can increase its permeability to hydrophilic substances. B Cell surface membrane permeability to large hydrophilic molecules is high and can be increased by membrane transport proteins involved in facilitated diffusion. C The permeability of the cell surface membrane to ions increases as the proportion of saturated fatty acid chains in the phospholipids increases. D Without the presence of carrier and channel membrane proteins, the cell surface membrane has a low permeability to large polar molecules.

7 ©EJC 2021 9744/01/J1H2PROMO/2021 [Turn over 10 The diagram below shows part of the cell surface membrane of an animal cell. Which statement(s) correctly describe(s) the movement of molecule(s) across this membrane? 1 Oxygen diffuses through molecules M. 2 Water may move through L via osmosis. 3 L has hydrophilic R groups that may allow facilitated transport of water. 4 Water may pass through M via osmosis. A 4 only B 1 and 3 only C 1, 2 and 3 only D All of the above 11 When living pancreatic cells were placed in a solution of a red stain called neutral red, the cytoplasm became red. The cells were then removed from the solution of neutral red. The red stain in the cytoplasm moved into vesicles, which were exported from the cell, eventually leaving the cell colourless. In another experiment, a respiratory inhibitor was placed into the solution and the cell remained colourless. Which transport mechanism(s) could explain how the red stain entered and left the cells? A active transport B osmosis and exocytosis C facilitated diffusion and endocytosis D active transport and exocytosis

8 ©EJC 2021 9744/01/J1H2PROMO/2021 12 The following statements describe various nucleic acids in eukaryotes. 1 a polynucleotide of variable length formed by a process which involves complementary base pairing 2 a small polynucleotide with a specific three-dimensional shape 3 a large polynucleotide with a specific shape associated with proteins 4 a large polynucleotide with supercoiled sections associated with proteins Which row correctly matches the description to the function of the nucleic acid? carrier of specific amino acids catalyst of protein synthesis carrier of coded information long-term storage of coded information A 2 4 3 1 B 3 2 4 1 C 2 3 1 4 D 1 3 2 4 13 Which sta