A cross between a parent who is heterozygous for a trait and a parent who is homozygous recessive would result in what possible percentage for their offspring?
100% chance of being homozygous dominant
50% chance of being heterozygous and a 50% chance of being homozygous recessive
25% chance of being homozygous recessive and a 75% chance of being heterozygous
50% chance of being homozygous dominant, 25% chance of being homozygous recessive and a 25% chance of being heterozygous
A cross between a parent who is heterozygous for a trait and a parent who is homozygous recessive would result in what possible percentage for their offspring?
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To understand this, let’s break it down step-by-step.
1. Identify the genotypes: The heterozygous parent (let’s call it Aa) has one dominant allele (A) and one recessive allele (a). The homozygous recessive parent (aa) has two recessive alleles.
2. Set up a Punnett square: This will help us visualize the crossing of these two parents. The alleles from each parent are placed on the top and sides of the square.
A a
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a | Aa | aa |
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a | Aa | aa |
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3. Analyze the results: From the Punnett square, we can see the possible offspring:
– Two squares show the heterozygous genotype (Aa).
– Two squares show the homozygous recessive genotype (aa).
4. Calculate percentages:
– 50% of the offspring will be heterozygous (Aa).
– 50% will be homozygous recessive (aa).
Thus, the correct answer is:
50% chance of being heterozygous and a 50% chance of being homozygous recessive.
This means that if you cross a heterozygous parent with a homozygous recessive parent, half of the offspring will be heterozygous and half will be homozyg