Biology · Oct / Nov 2025 · Paper 62 · Question 3

single clear outline with no shading ;

width of drawing greater than 93 mm ;

detail 1: 5 arms and enclosed shape in middle that doesn’t touch the edges ;

detail 2: indication of where colour changes on all limbs

length of line PQ: 93 ±1 (mm) ;

290 ;;

max two differences from:

spiny starfish

necklace starfish

/ Figure 3.2

/ Figure 3.3

spines / AW

AND smooth / scales / no spines ; light / bright, in centre

AND dark in centre ;

has five, ossicles / AW,

does not have five,

in the centre or has a

ossicles / AW, in the centre AND

central pentagon

or no central pentagon

shape

shape ;

no white ends to the

AND white ends to the limbs ;

limbs

more uniform shaped

AND less uniform shaped limbs ; limbs

straight limbs

AND bent / curved / AW, limbs ;

lines going down the

AND no lines going down the

arms

arms ;

max one similarity from:

(both have)

five, arms / AW ;

circle in the middle ;

dark arms / arms that are a different colour to the centre ;

tapering limbs ;

radial symmetry ;

any two from:

same region ;

same size of area / 20 m2, (sampled) ;

same day / same time of year / both in July / same date ;

depth measured at, same time of tide / high tide / when water at its highest ;

axes labelled with units ;

suitable linear scale on number of starfish axis and ranges given for depth axis and data occupies at least half the grid in both directions ; five accurate plots ± half a small square ;

bars of equal width ± half a small square with no gaps between them ;

10–19.9

total number of starfish photographed: 3428 ;

percentage in the 0.0–9.9m range: 10 (%) ;;