AQA 2024 AS BIOLOGY 7401/1 Paper 1 Specimen
01z.z1)zDescribezhowzyouzcouldzusezcellzfractionationztozisolatezchloroplastszfromzleafztissue.z[3zmarks]z-
zCORRECTzANSWER-1.zHowztozbreakzopenzcellszandzremovezdebris;
2.zSolutionziszcold/isotonic/buffered;
3.zSecondzpelletziszchloroplast;
01z.z2)z(Figurez1zshowszazphotographzofzazchloroplastztakenzwithzanzelectronzmicroscope.
Figurez1)
NamezthezpartszofzthezchloroplastzlabelledzAzandzB.
z [2zmarks]z-zCORRECTzANSWER-1.zAzstroma;
2.zBzgranum;
01z.z3)zCalculatezthezlengthzofzthezchloroplastzshownzinzFigurez1.
z [1zmark]z-zCORRECTzANSWER-(lengthzofzchloroplast/lengthzofzbar)um
01z.z4)zNameztwozstructureszinzazeukaryoticzcellzthatzcannotzbezidentifiedzusingzanzoptical
microscope.
z [1zmark]z-zCORRECTzANSWER-Mitochondrion/ribosome/endoplasmic
reticulum/lysosome/cell-surfacezmembrane
02z.z1)zAztechnicianzinvestigatedzthezeffectzofztemperaturezonzthezratezofzanzenzyme-controlled
reaction.zAtzeachztemperature,zhezstartedzthezreactionzusingzthezsamezvolumezof
substratezsolutionzandzthezsamezvolumezofzenzymezsolution.
Figurez2zshowszhiszresults.z
, Givezonezotherzfactorztheztechnicianzwouldzhavezcontrolled.
z [1zmark]z-zCORRECTzANSWER-Concentrationzofzsubstratezsolutionz/zofzenzyme
solutionz/zpH;
02z.z2)zCalculatezthezratezofzreactionzatz25zC.
z [2zmarks]z-zCORRECTzANSWER-1.z2.5/0.04;
2.zgzdm-3zminute-1z/zgzdm-3zs-1
;
02z.z3)zDescribezandzexplainzthezdifferenceszbetweenztheztwozcurves.
z [5zmarks]z-zCORRECTzANSWER-1.zInitialzratezofzreactionzfasterzatz37z°C;
2.zBecausezmorezkineticzenergy;
3.zSozmorezE-Szcollisions/morezE-Szcomplexes
formed;
4.zGraphzreacheszplateauzatz37z°C;
5.zBecausezallzsubstratezusedzup;
03z.z1)zFigurez3zsummariseszthezprocesszofzmeiosis.zThezcircleszrepresentzcellszandzthe
structureszwithinzeachzcellzrepresentzchromosomes.
DescribezandzexplainzthezappearancezofzonezofzthezchromosomeszinzcellzX.
z [3zmarks]z-zCORRECTzANSWER-1.zChromosomeziszformedzofztwozchromatids;
2.z(Because)zDNAzreplicationz(haszoccurred);
3.z(Sister)zchromatidszheldztogetherzby
centromere;
03z.z2)zDescribezwhatzhaszhappenedzduringzdivisionz1zinzFigurez3.
z [2zmarks]z-zCORRECTzANSWER-1.zChromosomeszinzhomologouszpair;
2.zOnezofzeachzintozdaughterzcellsz/zhaploid
01z.z1)zDescribezhowzyouzcouldzusezcellzfractionationztozisolatezchloroplastszfromzleafztissue.z[3zmarks]z-
zCORRECTzANSWER-1.zHowztozbreakzopenzcellszandzremovezdebris;
2.zSolutionziszcold/isotonic/buffered;
3.zSecondzpelletziszchloroplast;
01z.z2)z(Figurez1zshowszazphotographzofzazchloroplastztakenzwithzanzelectronzmicroscope.
Figurez1)
NamezthezpartszofzthezchloroplastzlabelledzAzandzB.
z [2zmarks]z-zCORRECTzANSWER-1.zAzstroma;
2.zBzgranum;
01z.z3)zCalculatezthezlengthzofzthezchloroplastzshownzinzFigurez1.
z [1zmark]z-zCORRECTzANSWER-(lengthzofzchloroplast/lengthzofzbar)um
01z.z4)zNameztwozstructureszinzazeukaryoticzcellzthatzcannotzbezidentifiedzusingzanzoptical
microscope.
z [1zmark]z-zCORRECTzANSWER-Mitochondrion/ribosome/endoplasmic
reticulum/lysosome/cell-surfacezmembrane
02z.z1)zAztechnicianzinvestigatedzthezeffectzofztemperaturezonzthezratezofzanzenzyme-controlled
reaction.zAtzeachztemperature,zhezstartedzthezreactionzusingzthezsamezvolumezof
substratezsolutionzandzthezsamezvolumezofzenzymezsolution.
Figurez2zshowszhiszresults.z
, Givezonezotherzfactorztheztechnicianzwouldzhavezcontrolled.
z [1zmark]z-zCORRECTzANSWER-Concentrationzofzsubstratezsolutionz/zofzenzyme
solutionz/zpH;
02z.z2)zCalculatezthezratezofzreactionzatz25zC.
z [2zmarks]z-zCORRECTzANSWER-1.z2.5/0.04;
2.zgzdm-3zminute-1z/zgzdm-3zs-1
;
02z.z3)zDescribezandzexplainzthezdifferenceszbetweenztheztwozcurves.
z [5zmarks]z-zCORRECTzANSWER-1.zInitialzratezofzreactionzfasterzatz37z°C;
2.zBecausezmorezkineticzenergy;
3.zSozmorezE-Szcollisions/morezE-Szcomplexes
formed;
4.zGraphzreacheszplateauzatz37z°C;
5.zBecausezallzsubstratezusedzup;
03z.z1)zFigurez3zsummariseszthezprocesszofzmeiosis.zThezcircleszrepresentzcellszandzthe
structureszwithinzeachzcellzrepresentzchromosomes.
DescribezandzexplainzthezappearancezofzonezofzthezchromosomeszinzcellzX.
z [3zmarks]z-zCORRECTzANSWER-1.zChromosomeziszformedzofztwozchromatids;
2.z(Because)zDNAzreplicationz(haszoccurred);
3.z(Sister)zchromatidszheldztogetherzby
centromere;
03z.z2)zDescribezwhatzhaszhappenedzduringzdivisionz1zinzFigurez3.
z [2zmarks]z-zCORRECTzANSWER-1.zChromosomeszinzhomologouszpair;
2.zOnezofzeachzintozdaughterzcellsz/zhaploid
