Fu Hua Sec 2024 Prelim 6093 Paper 2 QP

[Turn Over Candidate Name: Class: Index No.: FUHUA SECONDARY SCHOOL Secondary Four Express PRELIMINARY EXAMINATION 2024 4E Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School Fuhua Secondary School BIOLOGY 6093/02 Paper 2 Candidates answer on the Question Paper No Additional Materials are required. DATE 22 August 2024 TIME 1115 – 1300 DURATION 1 hour 45 minutes READ THESE INSTRUCTIONS FIRST Write your name, class and index number on all the work you hand in. Write in dark blue or black pen. You may use an HB pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, glue or correction fluid. Section A Answer all questions. Write your answers in the spaces provided. Section B Answer one question. Write your answers in the spaces provided. The use of an approved scientific calculator is expected, where appropriate. The number of marks is given in brackets [ ] at the end of each question or part question. FOR EXAMINER’S USE PARENT’S SIGNATURE Section A Section B Total /70 /10 /80 Setter(s): Mr Joshua Tan Vetter(s): Mr Owen Tan, Mr Nicholas Liu This document consists of 18 printed pages, including this page.

2 Section A Answer all questions. 1 Pectin, a type of carbohydrate, is one of the components of cell walls which are essential to maintaining the structure of plant cells. Tomatoes are firm when unripe but soften when ripening due to the hydrolysis of these cell wall components by enzymes , including polygalacturonase. The activity of polygalacturonase can be described as follows: pectin mono-galacturonate (a) Using the ‘lock and key’ hypothesis, describe the action of polygalacturonase. …………………………………………………………………………………………………….. …………………………………………………………………………………………………….. …………………………………………………………………………………………………….. …………………………………………………………………………………………………….. …………………………………………………………………………………………………….. …………………………………………………………………………………………………….. ………………………………………………………………………………………………. [4] The activity of polygalacturonase can be triggered by ethylene, which is released as a gas by some ripening fruits. An experiment was carried out to investigate the effect of spraying a liquid form of ethylene on the ripenin