Biology · May / June 2026 · Paper 42 · Question 2

1

produced as rapidly as it is used ;

2

(idea that it) does not run out ;

any three from:

1

plants / producers / phytoplankton / algae (use light) to

photosynthesise ;

2

light energy is converted to, chemical energy / glucose ;

3

more, plants / producers / food / (chemical) energy / biomass (for the fish) ;

4

(so more / faster) production of new cells / (named) tissues (in fish) ; 5

AVP ;

nitrate ;

(needed for,) growth / repair (tissues) / AVP ;

eutrophication ;

any four from:

1

holes should be large ; ora

2

small / young / non-target / AW, fish escape

OR only, large / old / target, fish are caught ;

3

small / young / escaped, fish are able to, grow (to adults) / reach sexual maturity / reach breeding age ; ora

4

(small / young / escaped fish) can reproduce ; ora

5

(results in) larger / maintains, populations / number, of a fish (species) (in the wild) ; ora

any six from:

1

climate change / global warming / (enhanced) greenhouse effect ; 2

(climate change / changed environment / less genetic variation) means that species less able to adapt / evolve (fast enough) ; 3,4 named example of habitat destruction ;;

5

(habitat destruction / pollution) causes a lack of (named) / more competition for, resources (necessary for survival) ;

6

hunting (by humans);

7

overharvesting ;

8,9 named examples of pollutants ;;

10 (hunting / overharvesting / pollution / habitat destruction / climate change / competition for resources) causes a decrease in, the population size / number of a species ;

11 (decreased population size results in) less genetic variation (within the species) ;

12 (decreased population size results in) reduced reproduction / harder to find a mate ;

13 introduced / invasive / alien, species OR new predator ;

14 causes (too much) competition with (local) species (for resources) ; 15 disruption of, food chain / web OR description ;

16 example of consequence of disrupted ecosystem ;

17 disease that kills, whole / most of a, population (before the population can recover) / AW ;

18 AVP ;

any five from:

1

ref. to (female given) fertility drugs / LH and FSH / drugs for ovulation / drugs for egg production (AI or IVF) ;

2

ref. to screening / selecting / quality checking, sperm

(AI / IVF) / embryos (IVF) / eggs (IVF) ;

3

freeze, semen / sperm (AI or IVF) / embryos (IVF) / eggs (IVF) OR use sperm bank (AI) OR use sperm (AI or IVF) or eggs (IVF) or embryos (IVF) collected, far away / long ago ;

artificial insemination

4

semen / sperm / male gamete, collected / extracted ;

5

semen / sperm / male gamete, inserted into, vagina / uterus / (near) cervix / oviduct ;

6

ref. to (sperm insertion) at the time, of fertility / ovulation ; in vitro fertilsation

7

gametes / eggs and sperm, collected / extracted ;

8

fertilisation / described, occurs, outside the body / in a dish / in a laboratory / AW ;

9

embryo inserted in uterus ;

10 AVP ;