Cambridge AssessmentInternational EducationCambridge International AS A LevelCANDIDATENAMECENTRECANDIDATENUMBERNUMBERBIOLOGY9700/42Paper 4 A Level Structured QuestionsFebruary/March 20232 hoursYou must answer on the question paper.No additional materials are needed.INSTRUCTIONS.Answer all questions.Use a black or dark blue pen.You may use an HB pencil for any diagrams or graphs.Write your name,centre number and candidate number in the boxes at the top of the page.Write your answer to each question in the space provided.Do not use an erasable pen or correction fluid.Do not write on any bar codes.You may use a calculator.You should show all your working and use appropriate unitsINFORMATION.The total mark for this paper is 100.The number of marks for each question or part question is shown in brackets ]This document has 28 pages.Any blank pages are indicated.DC(CE/SG)315750/3©UCLES2023[Turn over21 (a)Fig.1.1 is a drawing of a longitudinal section(LS)of a human kidney.Fig.1.1Use the letters A,B,C and D in Fig.1.1 to complete Table 1.1.Each letter may be used once,more than once or not at all.For each description,list all the letters that are correct.Table 1.1descriptionregion ofkidneylocation of loops of Henlelocation of Bowman's capsuleslocation of glomerulicontains urine at final concentration[4(b)The volume and water potential of the urine produced by the kidney vary according to thewater potential of the blood.This is a result of osmoregulation.Describe the role of aquaporins in osmoregulation.3(c)Describe the role of the brain in osmoregulation when the water potential of the bloodincreases above the set point.[Total:10]©UCLES20239700/42/FM23