In a monohybrid cross between 2 heterozygous individuals, a phenotypic ratio of (2:1) emerges due to__________________?
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Answer: B. Dominant lethal genes in homozygous individuals
Explanation
A two to one ratio often signals homozygous dominant lethal alleles. Individuals carrying the lethal combination fail to survive embryogenesis. This altered Mendelian ratio reflects differential mortality among specific genotype classes. Standard monohybrid heterozygous crosses typically produce a three to one phenotypic ratio. Lethal genes cause the death of an organism possessing them. Homozygous dominant genotypes may disrupt essential developmental pathways entirely.
Geneticists study lethal alleles to understand embryonic development and lethal mutations. Such genetic anomalies help explain unexpected deviations in breeding outcomes. Crop researchers monitor population ratios to detect recessive or dominant lethal factors. Lethal genes in heterozygotes would eliminate the entire population rapidly. Dominant epistasis produces a twelve to three to one ratio instead. None of the above is incorrect because the correct mechanism is listed.
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- Agriculture
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- Agriculture
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- medium
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