Thursday 9 June 2022 – Afternoon A Level Biology B (Advancing Biology) H422/01 Fundamentals of biology

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Thursday 9 June 2022 – Afternoon A Level Biology B (Advancing Biology) H422/01 Fundamentals of biology Time allowed: 2 hours 15 minutes * H 4 2 2 0 1 * INSTR... UCTIONS • Use black ink. You can use an HB pencil, but only for graphs and diagrams. • Write your answer to each question in the space provided. If you need extra space use the lined pages at the end of this booklet. The question numbers must be clearly shown. • Answer all the questions. • Where appropriate, your answer should be supported with working. Marks might be given for using a correct method, even if your answer is wrong. INFORMATION • The total mark for this paper is 110. • The marks for each question are shown in brackets [ ]. • Quality of extended response will be assessed in questions marked with an asterisk (*). • This document has 40 pages. ADVICE • Read each question carefully before you start your answer. © OCR 2022 [601/4720/9] DC (CE/JG) 301318/6 OCR is an exempt Charity Turn over SECTION A You should spend a maximum of 40 minutes on this section. Write your answer for each question in the box provided. Answer all the questions. 1 Stomatal conductance is a measure of the rate of diffusion of water vapour through the stomata of a leaf. Which of the environmental factors would cause an increase in stomatal conductance? A Decrease in temperature B Increase in humidity C Increase in wind speed D Reduced light intensity Your answer [1] 2 The photomicrograph shows a section through the stem of a sunflower, Helianthus annuus. Which of the options correctly identifies what is shown in the photomicrograph? A It shows phloem tissue in longitudinal section. B It shows phloem tissue in transverse section. C It shows xylem tissue in longitudinal section. D It shows xylem tissue in transverse section. Your answer [1] 3 Which part of a chloroplast contains the enzymes required for the light-independent reaction? A Granum B Inner membrane C Intergranal lamella D Stroma Your answer [1] 4 Which of the options would not prevent a climax community from forming? A Animal grazing B Coppicing C Pine forest plantation D Volcanic eruption Your answer [1] 5 Which nitrogenous base pairs with adenine during DNA replication? A Cytosine B Guanine C Thymine D Uracil Your answer [1] 6 The structure of a polymer is shown below. HOCH2 H OH O H HO CH OH H O CH2 H OH O CH2 H H OH OH O H HO CH OH H O H HO CH OH H 29 repeating units Which type of bond is broken down during the hydrolysis of this polymer? A Ester B Glycosidic C Peptide D Phosphodiester Your answer [1] 7 Water forms pleural fluid, a lubricant that reduces the friction between the lungs and the thoracic cavity during ventilation. Which of the statements about the properties of water explains its function as a lubricant? A A large amount of energy is required to change its temperature. B A large amount of energy is required to change liquid water into a vapour. C Adhesion allows water molecules to bond to surfaces. D It is a solvent. Your answer [1] 8 A scientist used a colorimeter during an investigation to measure the concentration of glucose in samples of urine. Which of the statements is/are correct? 1 The scientist used Benedict’s solution as a reagent. 2 The scientist checked the zero value of the colorimeter with distilled water to reduce systematic error. 3 The scientist assessed repeatability by repeating the measurements and calculating a mean. A 1, 2 and 3 are correct B Only 1 and 2 are correct C Only 2 and 3 are correct D Only 1 is correct Your answer [1] 9 Chelating agents are chemical compounds that target and react with metal ions in the body allowing them to be excreted. A chelating agent has been shown to reduce tissue damage caused by a protease enzyme in snake venom by preventing zinc ions (Zn2+) binding to the enzyme. Which of the statements about the protease enzyme is correct? A The chelating agent is a cofactor for the protease enzyme. B The chelating agent is a competitive inhibitor of the protease enzyme. C Zn2+ is a cofactor for the protease enzyme. D Zn2+ is a competitive inhibitor of the protease enzyme. Your answer [1] 10 The reaction shows the breakdown of ATP to release energy. ATP ADP + Pi Which type of reaction is involved in the breakdown of ATP? A Condensation B Hydrolysis C Oxidation D Phosphorylation Your answer [1] 11 Flow cytometry can be used to determine the concentration of bacterial cells in a sample by comparing fluorescently-stained bacterial cells with a known concentration of fluorescent beads by recording the number of events. An event occurs when a single cell or particle is detected by the flow cytometer. The results are shown in the table. Number of events Fluorescent beads 1500 Bacterial cells 3500 Concentration of bacterial cells = number of cell events × concentration of beads The known concentration of fluorescent beads is 15 000 per cm3. Which option shows the correct concentration of bacterial cells in 1 cm3 of the sample? A 6.4 × 103 B 1.6 × 10–4 C 3.5 × 104 D 2.9 × 10–5 Your answer [1] 12 The following scattergram was plotted using a set of data obtained during a practical investigation. Dependent variable Independent variable Which option describes the correlation shown between the independent and dependent variable? A No correlation B Strong positive correlation C Weak negative correlation D Weak positive correlation Your answer [1] 13 A student investigating the effect of ageing on short-term memory collected data from two groups of adults of different age ranges. Each group contained 15 adults. The student analysed their data with a Student’s unpaired t-test and used a critical values table at a 5% significance level to determine whether to reject their null hypothesis. What is the correct number of degrees of freedom used by the student when using the critical values table? A 14 B 15 C 28 D 30 Your answer [1] 14 Researchers studying a population of mona monkeys, Cercopithecus mona, noticed that one of the 490 monkeys had black fur rather than the usual grey and white fur. The researchers concluded that the monkey with black fur had a homozygous recessive genotype. What is the correct method to estimate the percentage of the mona monkey population who were heterozygous for fur colour? A Chi squared test B Hardy-Weinberg principle C Spearman’s rank correlation coefficient D Student’s paired t-test Your answer [1] 15 Which of the options is a correct definition of the genetic term it describes? A Genotype is the genetic composition of an organism. B Heterozygous is having two different genes of an allele. C Locus is an organism’s observable characteristics. D Phenotype is the position of a gene on a chromosome. Your answer [1] 16 A group of students were investigating the inheritance of eye colour in Drosophila melanogaster, fruit flies. • The gene for eye colour is sex-linked. • The allele, R, for red eyes is dominant. • The allele, r, for white eyes is recessive. The students carried out the following cross and observed the eye colour of the offspring. × XRY XrXr Which of the options about the eye colour of the offspring is correct? A All female offspring will have white eyes. B All male offspring will have white eyes. C All the offspring, male and female, will have red eyes. D Of the female offspring, 50% will have white eyes and 50% will have red eyes. Your answer [1] 17 The evolution of language in humans is a difficult topic for scientists to study. Which of the statements about the methods used to study language evolution is/are correct? 1 Genes known to be involved in speech and language can be studied. 2 Scientists can make comparisons with other species. 3 Scientists can study similarities in cytochrome c. A 1, 2 and 3 are correct B Only 1 and 2 are correct C Only 2 and 3 are correct D Only 1 is correct Your answer [1] 18 DNA ligase is an enzyme used in genetic engineering to produce human proteins from bacterial cells. Which of the statements about DNA ligase is/are correct? 1 It is used to join ‘sticky ends’ of DNA fragments. 2 It is a type of restriction enzyme. 3 It produces a single strand of DNA (cDNA) from mRNA. A 1, 2 and 3 are correct B Only 1 and 2 are correct C Only 2 and 3 are correct D Only 1 is correct Your answer [1] 19 The thermoregulatory centre has a role in controlling body temperature. Which structure contains the thermoregulatory centre? A Adrenal gland B Hypothalamus C Pancreas D Pituitary gland Your answer [1] 20 Which statement explains how the release of thyroxine helps to raise body temperature in cold conditions? A It causes an increase in metabolic rate. B It causes contraction of erector muscles in hair follicles. C It causes vasoconstriction. D It causes vasodilation. Your answer [1] 21 Which hormone is released by the kidney? A Antidiuretic hormone (ADH) B Erythropoietin C Glucagon D Insulin Your answer [1] [Show More]

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