2017 TYS Answers (ThatBioTutor).docx

Credit:WrittenbythecollectiveeffortofourtutorsatThatBioTutor. Youarewelcometosharethesewithanyoneyou’dlike!Justdon’tsellthemforprofit:) TYSAnswers2017(ThatBioTutorEdition) IMPTNOTE:- Fordifferencesbetween2023and2024syllabus,seethislisthere.- *Shadedblack=outofsyllabusfrom2024onwards Question Ans Question Ans1 C 21 D2 A 22 D3 A 23* B4 D 24 C5 B 25 A6 D 26 A7 C 27 B8 B 28 A9 B 29 B10 C 30 D11 A 31 B12 A 32* C13 C 33* A14 B 34 C15 C 35 C16 A 36 A17 C 37 C18 B 38 D19 A 39 A20 A 40 B *23:OptionA, hairerectormuscles,outofsyllabus,buttheotheroptionsareinsyllabus Stillwantmore?www.thatbiotutor.com- www.instagram.com/thatbiotutor/-www.youtube.com/@thatbiotutor- www.tiktok.com/@thatbiotutor

Credit:WrittenbythecollectiveeffortofourtutorsatThatBioTutor. Youarewelcometosharethesewithanyoneyou’dlike!Justdon’tsellthemforprofit:) Q1.(a)● Itisthemaintenanceofaconstantinternalenvironment,● Usingnegativefeedbacktocounteractchangesinthesystemtorestoretheset-point. (b)● Aductlessglandthatsecreteshormonesdirectlyintobloodstream,● whichtravelto,andalterstheactivityofoneormorespecifictargetorgans. (c)(i) ● A:Glycogen● B:Glucagon (ii)● Duringexercise,muscularcontractionsdemandlargeamountsofenergygeneratedbyaerobicandanerobicrespiration,● Bothofwhichinvolvesoxidisingglucose,hencemusclecellsuseupalotofbloodglucoseandcauseitsconcentrationtofall. Stillwantmore?www.thatbiotutor.com- www.instagram.com/thatbiotutor/-www.youtube.com/@thatbiotutor- www.tiktok.com/@thatbiotutor

Credit:WrittenbythecollectiveeffortofourtutorsatThatBioTutor. Youarewelcometosharethesewithanyoneyou’dlike!Justdon’tsellthemforprofit:) Q2.(a)● Cisoneofthelargeintercellularairspacesthatdecreasetheoveralldensityoftheleaf,sothatitislessdensethanwaterandallowstheleaftofloat. (b)● Theyarepositionednearthetopoftheleaf,justbeneaththeupperepidermis,sotheycanreceivemaximumsunlightforphotosynthesis. (c)● Chlorophyllinchloroplastsabsorblightenergyandconvertsitintochemicalenergy,● whichisusedtoconvertcarbondioxideandwaterintoglucoseandoxygen.● Usinghydrogenatomsandchemicalenergy, carbondioxideisreducedtoformglucoseduringphotosynthesis. (d) Stillwantmore?www.thatbiotutor.com- www.instagram.com/thatbiotutor/-www.youtube.com/@thatbiotutor- www.tiktok.com/@thatbiotutor

Credit:WrittenbythecollectiveeffortofourtutorsatThatBioTutor. Youarewelcometosharethesewithanyoneyou’dlike!Justdon’tsellthemforprofit:) Q3.(a)● Ittakesupthefirsttrophiclevelinthefoodweb,itmakesitownfoodfrominorganicmaterialslikecarbondioxide,andpassesenergyupthefoodwebtotherestoftheorganisms. (b)● Trophiclevel2:74(9+36+29)● Trophiclevel3:10(4+6)● Trophiclevel4:2 (c) Stillwantmore?www.thatbiotutor.com- www.instagram.com/thatbiotutor/-www.youtube.com/@thatbiotutor- www.tiktok.com/@thatbiotutor

Credit:WrittenbythecollectiveeffortofourtutorsatThatBioTutor. Youarewelcometosharethesewithanyoneyou’dlike!Justdon’tsellthemforprofit:) Q4.(a)● Beforetheexperiment,weigheachplantusinganelectronicbalance.Afterevery24hours,weigheachplantagain.● Subtracteachday’snewwe