DHS Prelim P1 P2

Name Index No. Civics Group ____________________________________________________________________________ DUNMAN HIGH SCHOOL SENIOR HIGH 2009 PRELIMINARY EXAMINATION General Certificate of Education Advanced Level YEAR SIX H1 BIOLOGY (8875) BIOLOGY 8875 / 01 PAPER 1 Multiple Choice 25 September 09 (Friday) 1 hour Additional Materials: Multiple Choice Answer Sheet ____________________________________________________________________________ READ THESE INSTRUCTIONS FIRST. Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid. Write your name, civics group and index number on the Answer Sheet in the spaces provided unless this has been done for you. There are thirty 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 the soft pencil on separate Answer Sheet [optical answer sheet (OTAS)] provided. 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. Calculators may be used. Do not open this booklet until you are told to do so. This question paper consists of 14 printed pages and 2 blank pages (including this cover page).

2 Section A: Multiple Choice Questions (30 marks) Answer all questions. 1 Which molecules, found in cell surface membranes, contribute to cell recognition? A cholesterol and glycolipids B cholesterol and phospholipids C glycolipids and glycoproteins D phospholipids and glycoproteins 2 Equal quantities of a 5% st arch solution were added to equa l quantities of different solutions. After 5 minutes at room temperature, th e solutions were tested with iodine in potassium iodide solution and the depth of colour was recorded using a colorimeter (with an arbitrary scale of 1 to 5, 5 being the darkest blue). The results are given in the table. solution colorimeter reading 1 saliva and dilute HCl 4 2 saliva and dilute NaHCO3 1 3 dilute HCl only 4 4 saliva at 100oC 5 5 saliva at 20oC 3 This experiment suggests that saliva contains a biologically active substance that __________. A hydrolyses starch in acid conditions B is denatured by hydrochloric acid C is promoted in its action by high temperatures D may be activated by hydrogencarbonate ions

3 3 Which of the following food samples r equires the largest amount of oxygen to oxidize it completely? A 1 g of amino acid B 1 g of fat C 1 g of monosaccharide D 1 g of polysaccharide 4 Which is the longest phase in the cell cycle of human liver cells? A prophase B anaphase C cytoplasmic cleavage D interphase 5 Down’s syndrome can exist in two forms. Classic Down’s syndrome affects all cells, while the mosaic form arises from the presence of two or more cell types in the body with differences in the chromosome number and structure. How does the mosaic condition arise? A non-disjunction of chromosomes in mitosis in early foetal development B non-disjunction of chromosomes in mitosis during formation of ova C non-disjunction of chromosomes in mitosis during formation of sperm D translocation of chromosomes at maturation of ovum or the sperm

4 6 An experiment is carried out to show that DNA replication is semi-conservative. Escherichia coli cells whose DNA contains only ‘heavy’ nitrogen (15N) are grown in a culture medium containi ng the normal isotope of nitrogen (14N) and allowed to divide three times. What will be the percentage of DNA molecules containing both forms of nitrogen after the third division? A 12.5% B 25% C 50% D 100% 7 Pyrimidine bases contain 4 carbon atoms and purine bases contain 5. How many carbon atoms does adenosine triphosphate contain? A 8 B 9 C 10 D 11 8 Transfer RNA __________. A forms hydrogen bonds between its codon and the anticodon of an mRNA in the A site of a ribosome B binds to its specific amino acid in the active site of an aminoacyl-tRNA synthetase C uses GTP as the energy source to bind its amino acid D is produced in the nucleolus

5 9 The table shows a comparison between the genomes of a prokaryote and a eukaryote. prokaryote eukaryote genome length (base pairs) 4,640,000 12,068,000 number of proteins 4,300 6,200 proteins with roles in metabolism 650 650 proteins with roles in energy release 240 175 proteins with roles in protein synthesis 410 750 Which feature of eukaryotes accounts for t he differences in the number of proteins with roles in protein synthesis? A The DNA of a eukaryote has histones. B The DNA of a eukaryote has introns. C The DNA of a eukaryote has more base pairs. D The DNA of a eukaryote is separated from the ribosomes by membranes. 10 Which best describes the correct order (from earliest to latest) in the control of gene expression in protein synthesis? A polyribosome, promoter, spliceosome, primary transcript B spliceosome, promoter, primary transcript, polyribosome C promoter, primary transcript, spliceosome, polyribosome D primary transcript, spliceosome, promoter, polyribosome 11 How is the coordinated transcription of genes involved in the same pathway regulated? A The genes are transcribed in one tr anscription unit, although each gene has its own promoter. B The genes are located in the same region of the chromosome, and enzymes deacetylate the entire region so that transcription may begin. C The genes all respond to the same general transcription factors, though they may respond to different specific transcription factors. D The genes have the same combination of control elements in the enhancer that bind with the particular activators present in the cell.

6 12 What do telomeres control? A cell adhesion B cell aging C cell fusion D cell differentiation 13 In a dihybrid cross of heterozygotes, what proportion of t he offspring will be phenotypically dominant for both traits? A 1/16 B 3/16 C 1/4 D 9/16 14 The base height of the dingdong plant is 10 cm . Four genes contribute to the height of the plant, and each dominant allele contributes 3 cm to height. If you cross a 10 cm plant (quadruply homozygous recessive) with a 34 cm plant, how many phenotypic classes will there be in the F 2? A 4 B 5 C 8 D 9

7 15 The family tree shows the inheritance of a skin condition. What is the genetic basis of the skin condition? A autosomal dominant B autosomal recessive C sex-linked dominant D sex-linked recessive 16 In a classic experiment on photosynthes is, R. L. Hill dem onstrated that an illuminated in vitro suspension of isolated chloroplasts could produce oxygen in the presence of a hydrogen acceptor such as methylene blue. In this case methylene is reduced. Which one of the following com pounds replaces methylene blue in the intact photosynthesising plant? A adenosine triphosphate (ATP) B carbon dioxide C nicotinamide adenine dinucleotide phosphate (NADP) D ribulose bisphosphate (RuBP)

8 Absorption spectra Chlorophyll a Chlorophyll b Carotenoids Action spectrum A 1 4 3 2 B 2 1 3 4 C 3 2 4 1 D 4 2 1 3 17 Three of the graphs below show the absorpt ion spectra of photosynthetic pigments. One graph shows the action spectrum of photosynthesis for a plant containing the pigments. All the x axes show wavelengt h. Three of the y axes s how light absorption. One y axis shows the rate of photosynthesis. Which of the following identifies the four graphs?

9 18 What are the structures labelled X and Y and what are their main functions? Structure X Function of X Structure Y Function of Y A granum photolysis of water stroma f