Biology · May / June 2025 · Paper 62 · Question 1

25 and 25 (cm3) ;

102 ±1 (mm) ;

table drawn with a minimum of three columns and a header line ;

suitable headings with correct units for concentration and length ;

five correct lengths recorded that match the salt solution concentration ;

S1: 8 (mm) and S2: 5 (mm) (S3 matches candidate’s measurement) ;

any one from:

the higher the concentration (of salt), the, more / faster, osmosis occurs ; the higher the concentration (of salt) the more water, is lost / moves out ; water move out of the, potato / disc(s), in salt solution(s) ;

water moves into the, potato / disc(s), when there is no salt / in pure water / in 0 mol dm3 ;

the solute concentration of the potato (cell(s)) is between 0.5 mol dm3 and 0 mol dm3 ;

length (of discs) ;

any one from:

change / difference, (in one disc) too small (to, measure / see) / ora ; one disc may not be, representative / typical ;

decreases / reduces, percentage error / AW ;

reduces the effect of anomalous results ;

solution: iodine (solution)

and

conclusion: starch present ;

Outline is a single clear line with no shading ;

Size –at least half the available space used ;

Detail 1: midrib as a double line for at least half its length ;

Detail 2: four bumps across the base of the leaf (two on either side of the petiole and two bulges at the edges) ;

PQ = 63 ± 1 (mm) ;

(×) 1.6 ;;

one difference from: ;

(potato / Fig. 1.5)

(tomato / Fig. 1.6)

more veins

OR

fewer veins

veins more

OR

veins less branched

branched

(outline / side / edge

AND (outline / side / edge

is)

is)

smooth / even / not

uneven / lobed / wavy

lobed

/ jagged / bumpy

single / undivided /

AND divided

not lobed ,leaf

leaf / leaflet / lobed (at

bottom)

symmetrical

AND not

symmetrical / irregular

shape

one similarity from: ;