Form 12: Predicting Phenotypic Ratios & Percentages
In this engaging exercise, students will explore the principles of Mendelian genetics by predicting phenotypic ratios and percentages in various genetic crosses, using Punnett squares and real-world examples to deepen their understanding of inheritance patterns and variations.
Questions
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MultiChoice
What is a phenotypic ratio?
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MultiChoice
What is the expected phenotypic ratio from crossing two heterozygous organisms (Aa x Aa)?
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MultiChoice
What percentage of offspring will show the dominant trait in a cross between two heterozygous parents (Bb x Bb)?
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MultiChoice
What percentage of offspring will show the recessive trait in a cross between two heterozygous parents (Bb x Bb)?
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MultiChoice
What is the phenotypic ratio when a heterozygous organism (Aa) is crossed with a homozygous recessive organism (aa)?
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MultiChoice
If 100% of offspring show the dominant phenotype, which cross could have produced them?
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MultiChoice
What percentage of offspring will show the dominant trait from a TT x Tt cross?
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MultiChoice
If a cross produces 50 black mice and 50 white mice (where black is dominant), what was the likely cross?
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MultiChoice
In pea plants, yellow seeds (Y) are dominant over green seeds (y). If two Yy plants cross and produce 400 seeds, how many are expected to be yellow?
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MultiChoice
In the same cross (Yy x Yy producing 400 seeds), how many seeds are expected to be green?
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MultiChoice
If a cross produces 75% round seeds and 25% wrinkled seeds, what were the parental genotypes?
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MultiChoice
If both parents are homozygous recessive (aa x aa), what percentage of offspring will show the dominant phenotype?