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Question
A person first crossed pure-bred pea plants having round-yellow seeds with pure-bred pea plants having wrinkled-green seeds and found that only A-B type of seeds were produced in the F1 generation. When F1generation pea plants having A-B type of seeds were cross-bred by self-pollination, then in addition to the original round-yellow and wrinkled-green seeds, two new varieties A-D and C-B type of seeds were also obtained.
(a) What are A-B type of seeds?
(b) State whether A and B are dominant traits or recessive traits.
(c) What are A-D type of seeds?
(d) What are C-B type of seeds?
(c) Out of A-B and A-D types of seeds, which one will be produced in (i) minimum numbers, and (ii) maximum numbers, in the F2 generation?
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Solution
(a) A-B type of seeds are round-yellow.
(b) A (round) and B (yellow) are dominant traits.
(c) A-D type of seeds are round-green.
(d) C-B type of seeds are wrinkled-yellow.
(e) In the F2 generations, (i) A-D type seeds will be produced in minimum numbers; (ii) A-B type of seeds will be produced in maximum numbers.
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