Biology · May / June 2025 · Paper 41 · Question 3

pollen tube ;

any three from:

pollen tube grows / AW (and enters ovule / ovary) ;

pollen / male, nucleus travels down (pollen) tube / style ;

(pollen and ovule) nuclei fuse ;

ref. to ovule ;

any three from:

1

lack of (named) pollinators ;

2

idea that plant is isolated / AW ;

3

uses less, pollen / energy ;

4

increased chance of, fertilisation / pollination / offspring ;

5

idea of (less genetic diversity is) beneficial if plant is well-adapted to its environment ;

6

AVP ;

any three from:

1

less / no, genetic variation ;

2

less likely to, survive / adapt to, changes in the environment ; 3

less resilience against disease / disease spreads more quickly ; 4

(increased risk of) extinction ;

5

ref. to likelihood of genetic disease ;

any two from:

mutation ;

random, mating / pollination ;

random fertilisation ;

AVP ;

any four from:

1

ref. to nuclear division ;

2

production of genetically identical cells ;

3

(copies of / replicated) chromosomes separate ;

4

chromosome number is maintained (in each daughter cell) / AW ; 5,6 named roles of mitosis ;;

stem (cells) ;