IGCSE Biology
1. Plant breeders wanted to produce a better variety of tomato by selective breeding.
Two plants, of the varieties Tangella and Piranto, were crossed.
(a) Some flowers of each variety were covered with cellophane bags.
The diagram shows a covered flower and a brush.
(i) Explain why some flowers were covered with cellophane bags during the selective breeding.
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(2)
(ii) Suggest why a brush was needed.
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(2)
(b) Information about each variety of tomato is shown in the table.
Which features of Piranto would the plant breeders wish to see in the new breed of tomato?
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(1)
(Total 5 marks)
2. The diagrams show stages in the transfer and copying of the gene for growth hormone.
(a) (i) Name the donor and recipient organisms for this gene transfer.
donor
Two plants, of the varieties Tangella and Piranto, were crossed.
(a) Some flowers of each variety were covered with cellophane bags.
The diagram shows a covered flower and a brush.
(i) Explain why some flowers were covered with cellophane bags during the selective breeding.
..........................................................................................................................
..........................................................................................................................
..........................................................................................................................
..........................................................................................................................
(2)
(ii) Suggest why a brush was needed.
..........................................................................................................................
..........................................................................................................................
..........................................................................................................................
..........................................................................................................................
(2)
(b) Information about each variety of tomato is shown in the table.
Which features of Piranto would the plant breeders wish to see in the new breed of tomato?
....................................................................................................................................
(1)
(Total 5 marks)
2. The diagrams show stages in the transfer and copying of the gene for growth hormone.
(a) (i) Name the donor and recipient organisms for this gene transfer.
donor