2024 VS Prelim Bio Paper 2 QP and Ans

BIOLOGY PAPER 2 Friday 23 August 2024 1 hour 45 minutes VICTORIA SCHOOL PRELIMINARY EXAMINATION SECONDARY FOUR READ THESE INSTRUCTIONS FIRST Do not open this booklet until you are told to do so. Write your name, class and register number in the spaces provided at the top of this page. 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. Setters: L. Ruiting and Nur’Shifa M. This Question Paper consists of 23 printed pages (including this cover page). [Turn Over Name Class Register Number 6093/02 24/4P/6093/02 For Examiner’s Use Section Marks A / 70 B / 10 Total / 80 VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHO OL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHO OL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL V ICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHOOL VICTORIA SCHO OL

2 ©Victoria School 24/4P/6093/02 [Turn over Section A Answer all questions. 1 Scientists investigated how the diet of rabbits affected their digestion and absorption of protein. The scientists fed rabbits an identical mass of food but varied the percentage of protein in the food. The scientists measured the mean mass of protein fed to the rabbits that was absorbed, which they then expressed as a percentage value. The results are shown in Fig. 1.1. Fig. 1.1 (a) State and explain one conclusion that can be made about the absorption of the products of protein digestion as the percentage of protein increased in the rabbits’ food. ..………………..……………………..….......…………………….…………..…….…… …..………………....…………………………....…..…..………………….………..…… ……...……………………………………………………....…………………………….. ………….………………………………..………..………..…….…….………………[2] percentage protein in diet mean percentage of ingested protein absorbed 80 60 40 20 0 2.2 2.4 2.6

3 ©Victoria School 24/4P/6093/02 [Turn over (b) The digestive system of a rabbit is shown in Fig. 1.2. Fig. 1.2 The food eaten by a rabbit is digested mainly by microorganisms in its caecum. The caecum is a section of intestine attached between the ileum and the large intestine. The resulting semi-digested material leaves the anus of a rabbit as soft, caecal droppings. The rabbit then eats these caecal droppings. Use this information and Fig. 1.2 to suggest how eating its own caecal droppings helps a rabbit’s digestion and absorption of dietary protein. ………………………………..………….…..……..…...……..……………………….… ……………………………………….……………….…………....……………………… …………………………………….………..…...……...………..…….….……………… ……………………………………….…...………..……...…………..…….…….……… …………………………………………....……………………………...……….………. …………………………………………….…………………...……………….………[3] [Total: 5] ileum stomach caecum large intestine anus

4 ©Victoria School 24/4P/6093/02 [Turn over 2 Fig. 2.1 shows the life cycle of the plant Coffea arabica (C. arabica). This plant produces seeds which are used to make coffee. Fig. 2.1 (a) (i) Define self-pollination. ………………………………………………….…………………………………... ……………………………………….……………………………………………... ………………………………………………………..…………………..….…..[2] (ii) State t wo cellular processes that allow a seedling to grow into a mature flowering plant. 1……..….………………………………………………………………..….……... 2…………………………………………………………………………………. [2] flower X self-pollination & development dispersal seeds germination growth

5 ©Victoria School 24/4P/6093/02 [Turn over (b) Fig. 2.2 shows a drawing of the C. arabica flower. Fig. 2.2 (Source: Drawing by Mariam Marand) (i) The line SL in Fig. 2.2 represents the length of the style of the flower. On Fig. 2.2, label clearly the anther. [1] (ii) A pollen tube grows out from each compatible pollen grain. Describe the events thereafter which lead to the formation of structure X in Fig. 2.1 and its contents. ………………………………………………..………………..…………………… …………………………………………………..…………………………..……… ………………………………………………………..…………………………….. …………………………………………………….....…………………………….. ……………………………………………………….……………………………... ...……………………………..………………………..………………………....[4]

6 ©Victoria School 24/4P/6093/02 [Turn over (c) C. arabica plants produce a chemical called caffeine which in high concentrations is toxic to insects. Suggest why it is important to the plant to have different concentrations of caffeine in different parts of the plant. ……………………………………………………...……………………………………... ………………………..……….……………...……………………………..….……...[1] [Total: 10] 3 (a) Fig. 3.1 shows the genitourinary system of a man. Fig. 3.1 (i) Name the parts labelled D and E. D: …………………………………………………… E: …………………………………………………… [2] (ii) Explain the role of structure F in fertilisation. ………………………………………………………...…….…………………...… ……………………………………………………………….…...………………… ……………………………………………………………….……………………... ……………………………………………………………….…...………………… ……………………………………………………………….……………………... ………………......…………………………………………….………………....[3] F E D

7 ©Victoria School 24/4P/6093/02 [Turn over (b) A couple could produce gametes but still could not produce children. A doctor advised them to undergo an in-vitro fertilisation (IVF) treatment. Fig. 3.2 outlines the stages involved in the IVF treatment. Fig. 3.2 (i) Suggest one possible cause of infertility for this couple. the man..…………………………………………………………………………… ……………………………………………………………………………………… the woman….……………………………………………………………………… ……………….…………………………………………………….…………….[2] (ii) Of the six embryos placed into the uterus , only two embryos developed successfully. Suggest why some embryos are not able to develop in the uterus. ……………………………………………………………………………………… ……..……………………………………………………………………….……[1] ovarian stimulation egg retrieval and sperm collection fertilisation embryo culture embryo transfer pregnancy

8 ©Victoria School 24/4P/6093/02 [Turn over (iii) State if it is possible for the two embryos to be of different sexes. Explain your answer. ……………………………………………………………………………………… ……………………………………………………………………………………… ...…………………………………………………………………………………[2] (iv) Explain why it is important that the foetal blood system in the placenta is not continuous with the maternal blood system. ……………………………………………………………………………………… ……………………………………………………………………………………… ……………………………………………………………………………………… ………………………………………………………………………………