Biology · May / June 2021 · Paper 42 · Question 6

prediction:

set, A / in bag, will lose less, mass (than set B) ;

explanation:

because high(er) humidity (in A) ;

less steep diffusion gradient / AW (in A) ;

less transpiration (in A) ;

any three from:

water evaporates ;

from (surface of) mesophyll / into air spaces ;

water vapour, diffuses / described ;

through stomata (out of leaf) / AW ;

balance / scale / AW ;

stop-clock / timer / AW ;

;; letter description

name of tissue P

a protective transparent layer that

upper epidermis allows light to reach inner tissues

Q

conducts water from the stem

xylem

R

contains many interconnected air

spongy mesophyll spaces

S

transports sucrose and amino acids

phloem

T

traps the most light energy to

palisade mesophyll synthesise carbohydrates

;;