Core · structured questions. Each generated paper follows the 0610 Paper 3 · Theory format, with the same number and style of questions as the real exam, and comes with a Cambridge-style mark scheme.
Describe how the sequence of bases in a gene controls the protein made.
[3]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
length of DNA coding for a protein
a length of DNA that codes for a protein B1
1
(b)
alternative form of a gene
an alternative form of a gene B1
1
(c)
triplets code amino acids; mRNA; ribosome
the base sequence determines the amino acid sequence B1 mRNA copies the gene and goes to a ribosome B1 amino acids are joined in that order B1
3
Question 2Structured · 7 marksA* challenge
Insect-pollinated and wind-pollinated flowers have different features.
(a)
Describe two features of a wind-pollinated flower.
[2]
(b)
Define pollination.
[2]
(c)
Describe what happens after a pollen grain lands on the stigma.
[3]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
small, dull, no nectar; feathery stigmas; large anthers outside; light pollen
Any 2 of: small, dull petals; anthers hanging outside; feathery stigmas; large amounts of light pollen B2
2
(b)
transfer of pollen from anther to stigma
the transfer of pollen grains from the anther B1 to the stigma B1
2
(c)
pollen tube grows, nucleus fuses with ovule
a pollen tube grows down the style B1 into the ovule B1 the male nucleus fuses with the female nucleus (fertilisation) B1
3
Question 3Structured · 6 marks
Bacteria are useful in biotechnology and genetic modification.
(a)
Give two reasons why bacteria are useful for biotechnology.
[2]
(b)
Describe how pectinase is used to make fruit juice.
[2]
(c)
Explain why biological washing powders work at low temperatures.
[2]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
reproduce rapidly; make complex molecules; plasmids
Any 2 of: reproduce rapidly; can make complex molecules; contain plasmids; few ethical concerns B2
2
(b)
breaks down pectin in cell walls, more juice
pectinase breaks down pectin in plant cell walls B1 more juice is released and it is clearer B1
2
(c)
enzymes digest stains at low temperature
enzymes (proteases/lipases) digest stains B1 they work at low temperatures, saving energy B1
2
Question 4Structured · 11 marks
This question is about reproduction in flowering plants.
(a)
Define pollination.
[1]
(b)
Describe two differences between insect-pollinated and wind-pollinated flowers.
[2]
(c)
Describe what happens after a pollen grain lands on the stigma, leading to fertilisation.
[3]
(d)
Distinguish between self-pollination and cross-pollination.
[2]
(e)
Explain why cross-pollination is an advantage to a species if the environment changes.
[3]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
transfer of pollen from anther to stigma
the transfer of pollen grains from an anther to a stigma B1
1
(b)
insect: large coloured petals, nectar; wind: small dull, feathery stigma outside, anthers hang out
Any 2 of: insect-pollinated have large coloured / scented petals and nectaries, wind-pollinated have small dull petals; wind-pollinated have feathery stigmas / anthers hanging outside the flower; wind-pollinated produce large amounts of light pollen B2
2
(c)
pollen tube grows down the style; to the ovule through micropyle; male nucleus fuses with female nucleus
a pollen tube grows from the pollen grain down through the style B1 it enters the ovule (through the micropyle) B1 the male nucleus fuses with the female nucleus (fertilisation) B1
3
(d)
self: same flower/plant; cross: different plant of same species
self-pollination: pollen from the same flower or plant B1 cross-pollination: pollen from a different plant of the same species B1
2
(e)
more genetic variation; some offspring may have advantageous features; species more likely to survive
cross-pollination produces more genetic variation B1 some offspring are more likely to have features suited to the new conditions B1 so the species is more likely to survive (adapt) B1
3
Question 5Structured · 2 marks
Water is important to organisms.
State two roles of water as a solvent in organisms.
[2]
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Part
Answer and marking points
Marks
digestion; excretion; transport
Any 2 of: in digestion; transport of substances (e.g. in blood plasma/xylem); excretion of urea in urine B2
2
Question 6Structured · 3 marks
The liver plays a role in excretion.
(a)
Name the product formed when excess amino acids are deaminated.
[1]
(b)
Explain why the body cannot store excess amino acids.
[1]
(c)
State one other function of the liver.
[1]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
urea
urea B1
1
(b)
no storage; toxic
amino acids cannot be stored in the body B1
1
(c)
breaks down alcohol/drugs; glycogen storage; bile
Any 1 of: breakdown of alcohol/drugs; converting glucose to glycogen; making bile B1
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Original Cambridge-style practice questions written for mentorriyaz.in. These are not Cambridge past paper questions, and this site is not affiliated with or endorsed by Cambridge University Press & Assessment. Updated 2026-11-04. Paper generator · mentorriyaz.in