2024 RI H2 Bio P3 QP

© RI 2024 Preliminary Examination 9744/03 [Turn over RAFFLES INSTITUTION 2024 Year 6 Preliminary Examination Higher 2 BIOLOGY 9744/03 Paper 3 Long Structured and Free-response Questions 11th Sept 2024 2 hours Candidates answer on the Question Paper. Additional Materials: Writing paper. R E A D T H E S E I N S T R U C T I O N S F I R S T Write your index number, CT group & name in the spaces at the top of this page. Write in dark blue or black pen. You may use a HB pencil for any diagrams or graphs. Do not use staples, paper clips, glue or correction fluid. Section A Answer all questions in the spaces provided on the Question Paper. Section B Answer any one question in the writing paper provided. The use of an approved scientific calculator is expected, where appropriate. You may lose marks if you do not show your working or if you do not use appropriate units. At the end of the examination, hand in your essay question SEPARATELY. The number of marks is given in brackets [ ] at the end of each question or part question. This document consists of 19 printed pages. CIVICS GROUP CANDIDATE NAME INDEX NUMBER 4 S 0 3 2 Raffles Institution Internal Examination For Examiner’s Use Section A 1 / 30 2 / 11 3 / 9 Section B 4 or 5 / 25 Total / 75

2 © RI 2024 Preliminary Examination 9744/0 3 For Examiner’s Use Section A Answer all the questions in this section. 1 The human papillomavirus (HPV) is sexually transmitted and can cause the development of cervical intraepithelial neoplasia (CIN). Patients with CIN are o b s e r v e d t o h a v e a b n o r m a l growth of cells that line the cervix. This can lead to the development of cervical cancer. Fig. 1.1 shows the structure of the HPV. Fig. 1.1 (a) With reference to Fig. 1.1, compare the structure of HPV with a T4 bacteriophage. .……………………………………………………...…………………………………………………… .……………………………………………………...…………………………………………………… ………………………………………………………...…………………………………………………. …………………………………………………………...………………………………………………. .………………………………………………………..………………………………………………… ………………………………………………………..………………………………………………[3] capsid protein L1 histone capsid protein L2 genomic DNA

3 © RI 2024 Preliminary Examination 9744/0 3 [Turn over For Examiner’s Use A recent study assessed the impact of routine vaccination against HPV on the development of CIN. Fig. 1.2 shows the effect of HPV vaccination on the percentage of women found to have the most severe grade of CIN by cervical screening over the years. Fig. 1.2 (b) With reference to Fig. 1.2, e x p l a i n h o w t h e d a t a s u p p o r t s t h e s u g g e s t i o n t h a t v a c c i n a t i o n against HPV could lead to herd immunity. .……………………………………………………...…………………………………………………… .……………………………………………………...…………………………………………………… ………………………………………………………...…………………………………………………. …………………………………………………………...………………………………………………. .………………………………………………………..………………………………………………… ………………………………………………………..………………………………………………[3]

4 © RI 2024 Preliminary Examination 9744/0 3 For Examiner’s Use (c) Fig. 1.3 shows the number of cases of cervical cancer and death rate from cervical cancer in females of different ages in one year. Fig. 1.3 With reference to Fig. 1.3, ( i ) describe changes that occur in the number of cases of cervical cancer from the ages of 20–29 to 90–99. ………………………………………………………………………………….………………… ………………………………………………………………………………….………………… ………………………………………………………………………………….………………… ………………………………………………………………………………………..………..[2] ( i i ) suggest a reason for the decrease in the death rate from cervical cancer between ages 80–89 and 90–99. …………………………………………………………………………………………………… …………………………………………………………………………………………………[1]

5 © RI 2024 Preliminary Examination 9744/0 3 [Turn over For Examiner’s Use ( i i i ) Express as a simplest whole number ratio, the number of cases compared to death rate at ages 30–39. [1] ______________: ________ number of cases : death rate ( i v ) The human papillomavirus (HPV) is commonly associated with cases of cervical cancer. Many countries have a vaccination programme against HPV. Use information from Fig. 1.3 to suggest why females are given the vaccine in their teenage years. …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………[2] ( v ) The HPV vaccination programme is being extended to boys’ schools. Explain the advantages of: offering the HPV vaccine to boys, …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………[2] and carrying out the vaccination programme in schools. …………………………………………………………………………………………………… …………………………………………………………………………………………………[1]

6 © RI 2024 Preliminary Examination 9744/0 3 For Examiner’s Use ( v i ) Similar to HPV infections, infections caused by the bacterium, Chlamydia trachomatis, are also sexually transmitted. E x p l a i n w h y t h e H P V v a c c i n e w i l l n o t p r o t e c t g i r l s f r o m C. trachomatis. … . . … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … … . . …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………… …………………………………………………………………………………………………[3] (d) Like HPV, the human immunodeficiency virus (HIV) may lay dormant in the body for years without causing symptoms. HIV is an example of a virus that spreads from other animals to h u m a n s w h e r e i t c a u s e s disease. Chimpanzees can carry the simian immunodeficiency virus (SIV), which is similar to HIV. It is thought that chimpanzees who carry antibodies for SIV do not become ill if infected with HIV. This has been investigated by scientists who are developing potential vaccines for HIV. Tests were carried out to see if antibodies against SIV present in chimpanzees bind to HIV antigens. Test strips which contained several different HIV antigens were prepared. When samples are applied to the test strip, a line will appear in the control region. If the sample contains antibodies to the HIV antigens present on the strip, additional lines will also appear. Samples of chimpanzee faeces were collected from a number of sites in Gabon in central Africa. The faecal samples were prepared and then applied to the test strips. ( i ) Suggest why the investigators collected faecal samples from chimpanzees rather than blood plasma samples. ……………………………………………………………………………………………………. ………………………………………………………………………………………………....[1]

7 © RI 2024 Preliminary Examination 9744/0 3 [Turn over For Examiner’s Use The scientists collected 608 faecal samples from 224 individual chimpanzees. ( i i ) Describe how an investigator can prepare the faecal samples before applying them to the test strips. …………………………………………………………………………………………………… ……………………………………………