NYGH 2018-S3EOY-IP Bio P2 Section A

Class Register Number Name NANYANG GIRLS’ HIGH SCHOOL End-of-Year Examination 2018 Secondary Three IP BIOLOGY Paper 2 Theory Paper 1 hour 45 minutes Friday 5 October 2018 1000 – 1145 Additional materials: Nil READ THESE INSTRUCTIONS FIRST Do not open this document until you are told to do so. Write your name, register number and class in the spaces at the top of this page. Section A Answer all questions. Write your answers in the spaces provided on the question paper. At the end of the examination, 1. fasten all your work securely together; 2. tick 8 Either or 8 Or in the grid-box to indicate the question answered. You are advised to spend no longer than 1 hour on Section A, and no longer than 45 minutes on Section B. The intended number of marks is given in the brackets [ ] at the end of each question or part question. The use of an approved scientific calculator is expected, where appropriate. EXAMINER’S USE Paper 1 (30 marks) Paper 2 Section A (40 marks) 1 (7 marks) 2 (8 marks) 3 (7 marks) 4 (9 marks) 5 (9 marks) Section B (30 marks) 6 (10 marks) 7 (10 marks) tick: 8 Either (10 marks) tick: 8 Or (10 marks) TOTAL (100 marks) Setter: LZJ This document consists of 11 printed pages and 1 blank page. NANYANG GIRLS’ HIGH SCHOOL [Turn over A

2018 End-of-Year Examination Secondary Three 2 Nanyang Girls’ High School IP Biology Section A Answer all questions. Write your answers in the spaces provided. 1 Fig. 1.1 shows an electron micrograph of a blood clot. Fig. 1.1 [adapted from Principles of Anatomy and Physiology, 14th Edition, Tortora et. al.] (a) Name the structures C and D. C ………………………… D ………………………… [2] (b) Explain how a blood clot is formed. …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… ………………………………………………………………………………………………...[3] (c) Sometimes blood clots can form inside a coronary artery. Explain how the blockage may affect the heart. …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… ………………………………………………………………………………………………...[2] [Total: 7] D C

2018 End-of-Year Examination Secondary Three 3 Nanyang Girls’ High School IP Biology [Turn over 2 Some people are unable to hydrolyse lactose (milk sugar) and have a condition known as lactose intolerance. Fig. 2.1 shows what happens in the intestine of a person who is lactose intolerant if they eat food containing large amounts of lactose. Fig. 2.1 [adapted from Biology November 2016/P4] (a) Write a word equation for the hydrolysis of lactose. ………………………………………………………………………………………………...[2] bacteria produce hydrogen, methane and carbon dioxide from stomach diarrhoea and gas not drawn to scale bacteria digest lactose to simple sugars movement of water molecules build-up of gas and water large intestine small intestine lactose molecule

2018 End-of-Year Examination Secondary Three 4 Nanyang Girls’ High School IP Biology (b) In the large intestine, the hydrolysis of lactose by the bacteria produces hydrogen gas. The gas is absorbed into the blood and removed through the lungs. Lactose intolerance can be monitored by measuring the hydrogen gas concentration in the exhaled air of a person. People who were lactose intolerance consumed the following milk products: • milk treated with lactase immediately before drinking • milk treated with lactase two days before drinking • yoghurt made by bacteria that hydrolysed the lactose in the milk • untreated milk The hydrogen gas concentration in the exhaled air was measured hourly for five hours following the consumption of each milk product. The average results are shown in Fig. 2.2. Fig. 2.2 [adapted from Biology November 2016/P4] (i) Based on the results in Fig. 2.2, complete Table 2.1. Table 2.1 graph milk product consumed W X Y Z [1] 0.0 2.5 3.5 4.5 5.0 1.0 3.0 4.0 1.5 2.0 0.5 time / hour W X Y Z hydrogen gas concentration in the exhaled air / parts per million (ppm) 10 0 20 30 40 60 50

2018 End-of-Year Examination Secondary Three 5 Nanyang Girls’ High School IP Biology [Turn over (ii) Suggest one impact of severe diarrhoea caused by lactose intolerance on the human health. …………………………………………………………………………………………… …………………………………………………………………………………………[1] (iii) Use the results in Fig. 2.2 to explain why milk product Z is the best for people with lactose intolerance. …………………………………………………………………………………………… …………………………………………………………………………………………… …………………………………………………………………………………………… …………………………………………………………………………………………[2] (c) Villi are found in the small intestine. Describe and explain two ways in which a villus is adapted for the absorption of digested food. 1. ………………………………………………………………………………………………… …………………………………………………………………………………………………… 2. ………………………………………………………………………………………………… ………………………………………………………………………………………………...[2] [Total: 8]

2018 End-of-Year Examination Secondary Three 6 Nanyang Girls’ High School IP Biology 3 (a) Both the Golgi apparatus and the rough endoplasmic reticulum (rER) are part of the internal network of membranes in cells. Describe two structural features that distinguish Golgi apparatus from the rough endoplasmic reticulum (rER). …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… ………………………………………………………………………………………………...[2] (b) The inner and outer membranes of a mitochondrion have a fluid mosaic structure similar to other cell membranes. Suggest one way in which the structure of the inner membrane may differ from that of the outer membrane resulting in a less permeable inner membrane. …………………………………………………………………………………………………… ………………………………………………………………………………………………...[1]

2018 End-of-Year Examination Secondary Three 7 Nanyang Girls’ High School IP Biology [Turn over (c) An experiment was carried out to trace the route of amino acids in animal cells. The cells were incubated for 5 minutes in a medium containing radioactively labelled amino acids. The radioactive amino acids were then washed off and the cells were incubated in a medium containing non-radioactive amino acids. Samples of the cells were taken at 5, 10 and 45 minutes after the start of the experiment and the sites of radioactivity in the cells were determined. The results are shown in Table 3.1. Table 3.1 organelle percentage of total radioactivity / % at 5 minutes at 10 minutes at 45 minutes rough endoplasmic reticulum 80 15 5 Golgi apparatus 10 65 25 secretory vesicles 0 5 70 (i) Explain why most of the radioactive amino acids move to the rough endoplasmic reticulum (rER) after 5 minutes. …………………………………………………………………………………………… …………………………………………………………………………………………[1] (ii) Using the data from Table 3.1, describe and explain the changes in the percentage of radioactivity in the Golgi apparatus over the course of the experiment. …………………………………………………………………………………………… …………………………………………………………………………………………… …………………………………………………………………………………………… …………………………………………………………………………………………… …………………………………………………………………………………………… …………………………………………………………………………………………[3] [Total: 7]

2018 End-of-Year Examination Secondary Three 8 Nanyang Girls’ High School IP Biology 4 Cystic fibrosis is a genetic disease which affects the 3-dimensional (3D) conformation of a protein that is responsible for the transport of chloride ions across cell membranes. Fig. 4.1 shows how a normal protein channel allows the transport of chloride ions to occur, which does not occur in cystic fibrosis protein channel. Fig. 4.1 [adapted from OCR Biology 2017/B2] (a) With r