Biology · May / June 2021 · Paper 61 · Question 2

axes: labelled with units as time (after exercise) / minutes

and pulse rate / beats per minute or bpm ;

scale: evenly scaled and plots occupying half of the grid in one direction ;

plots: all correct ± half a small square ;

line: smooth curve (through at least 4 plots) or plot points joined with ruled lines ;

any two from:

pulse rate decreases as time increases / AW ;

biggest decrease in pulse rate is in first, one / two, minute(s) / initially ;

plateaus or levels off / returns to pre-exercise pulse rate / returns to 62 (bpm) (at 4 mins) ;

60.26 (%) ;;;

pulse rate ;

120 bpm is an anomalous result / AW ;

(idea that anomalous / AW data), should not be included in an average ;

similarity, max one from ;

both have, a wall / layers

both have, central space / lumen / AW

both contain blood (cells)

differences, max two from ;;

artery wall is thicker / vein wall is thinner

inner surface of artery more irregular / AW ora

lumen AW, smaller in artery / ora

vein (overall) is bigger / ora

artery (overall or lumen) circular / AW, and vein irregular (in shape) / AW