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A number of different alleles have been discovered at the 'C' locus in white clover plants - VCE - SSCE Biology - Question 21 - 2011 - Paper 1
Question 21
A number of different alleles have been discovered at the 'C' locus in white clover plants. These plants prevent self-fertilisation by allele incompatibility. A fema... show full transcript
Worked Solution & Example Answer:A number of different alleles have been discovered at the 'C' locus in white clover plants - VCE - SSCE Biology - Question 21 - 2011 - Paper 1
Step 1
The cross likely to produce the greatest number of viable seeds is:
Answer
To determine which cross produces the greatest number of viable seeds, we analyze the allele compatibility of each cross.
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Cross W: The plant has genotype C₄C₂ and produces pollen with allele C₄C₈. Here, C₄ will not fertilize a female gamete containing C₄. However, C₂ can potentially fertilize a female gamete that does not contain C₂.
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Cross X: The genotype is C₄C₃, producing C₁C₇ pollen. The allele C₄ may not fertilize female gametes containing C₄, but C₃ can potentially fertilize many combinations unlike others.
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Cross Y: With the genotype of C₇C₈, pollen of C₂C₈ may have restrictions with its compatibility but shows potential with more combinations.
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Cross Z: The genotype of C₄C₈ showing pollen C₆C₈ creates limitations as the C₄ pollen can’t fertilize C₄ female gametes.
By analyzing these compatibility restrictions and the diversity of alleles, Cross X (B) is likely to yield the greatest number of viable seeds, as it allows for versatile fertilization opportunities with the least restrictions.