Question 1
Which statement about asexual reproduction is correct?
- It involves two parents
- It involves the fusion of gametes
- The offspring are genetically identical to the parent
- It produces a lot of variation
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Answer: C (1)
Question 2
Describe what happens in fertilisation and what happens to the zygote afterwards.
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- nucleus of a male gamete fuses with the nucleus of a female gamete (1)
- to form a zygote (1)
- the zygote divides (by cell division) and develops into an embryo (1)
Question 3
A wind-pollinated flower has anthers that hang outside the flower and a large feathery stigma. Explain how these two features help the flower to be pollinated.
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- anthers hang outside the flower / on long filaments (1)
- so pollen is easily blown away / carried by the wind (1)
- feathery stigma has a large surface area (1)
- so it can catch pollen from the air (1)
- allow stigma hangs outside the flower so it can catch pollen
Question 4
Describe how fertilisation takes place in a flowering plant after a pollen grain has landed on the stigma.
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- a pollen tube grows from the pollen grain (1)
- down through the style to the ovary / into the ovule (1)
- the nucleus of the male gamete fuses with the nucleus of the female gamete (egg cell) (1)
Question 5
A student sets up three test tubes of cress seeds to investigate the conditions needed for germination. Tube 1 has damp cotton wool at room temperature. Tube 2 has dry cotton wool at room temperature. Tube 3 has damp cotton wool in a refrigerator. All three tubes are kept in the dark. Only the seeds in tube 1 germinate. State what the student can conclude and give two variables that should be kept the same.
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- water is needed for germination (1)
- a warm / suitable temperature is needed for germination (1)
- same type / number of seeds (1)
- same amount of cotton wool / same time / same light (1)
- allow any sensible control variable
Question 6
Explain why a germinating seed can grow even though it is buried in soil and cannot yet photosynthesise.
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- the seed contains stored food / starch / oil (1)
- enzymes break down the food reserves (1)
- to release energy by respiration / provide materials for growth until leaves can photosynthesise (1)
Question 7
Compare the structure of an insect-pollinated flower with a wind-pollinated flower and explain how each is adapted for pollination.
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| Level | Marks | What the answer does |
|---|---|---|
| 3 | 5–6 | A detailed and accurate comparison of both flower types, with several structures described and the adaptations clearly explained in terms of pollination. Both types are covered in balance. |
| 2 | 3–4 | Some accurate description of structures and some explanation, but the answer may be unbalanced or have limited explanation of how each feature helps pollination. |
| 1 | 1–2 | A few simple statements about the flowers, with little or no explanation. The comparison may be missing. |
Indicative content
- insect-pollinated: large, brightly coloured, scented petals to attract insects
- insect-pollinated: nectaries make nectar as food for insects
- insect-pollinated: anthers and stigma inside the flower so insects brush against them
- insect-pollinated: pollen is sticky or spiky so it sticks to insects; stigma is sticky
- wind-pollinated: small, dull petals (no need to attract insects), no nectar or scent
- wind-pollinated: anthers hang outside on long filaments so wind can blow pollen away
- wind-pollinated: pollen is light and made in large amounts
- wind-pollinated: large feathery stigma outside the flower to catch pollen from the air
Question 8
A gardener takes cuttings from a rose plant that has large red flowers. State what the gardener can expect about the new plants and explain why.
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- the new plants will have large red flowers / will be the same as the parent (1)
- they are genetically identical to the parent / clones (1)
- because they are produced by asexual reproduction / only one parent / no gametes involved (1)