Question

A) A man and woman both have freckles and they are both heterozygous for the trait. They have three

children, and none have freckles. What is the predicted probability vs. actual results. Explain why real
examples do not always follow the Punnett square.

Answer 1

In Biology, a Punnett square predicts a 75% chance of children inheriting freckles if both parents are heterozygous, but actual genetic outcomes may vary due to random chance and small sample sizes.

Step-by-step explanation:

The subject of the question is Biology, and it pertains to genetics and the use of Punnett squares to predict the inheritance of traits. When both parents are heterozygous for a trait with simple dominance, such as freckles (represented by alleles 'Bb'), a Punnett square predicts a phenotypic ratio of 3:1 for the offspring. This means there is a 75% chance for offspring to exhibit freckles.

However, in real-life genetics, the predicted probabilities from a Punnett square might not always be reflected in actual results due to the influence of random chance, especially in small sample sizes such as human families. Although the predicted probability of each child having freckles is 75%, none of the three children have freckles, which is statistically possible but not the most likely outcome. The discrepancy between expected and actual results highlights how random segregation of alleles and statistical variability can influence genetic inheritance

Answer 2

When both parents are heterozygous for a trait, the Punnett square predicts a 25% chance of their children not having the trait. However, real examples can deviate from this probability due to genetic recombination during meiosis.

Step-by-step explanation:

Based on the given information, the parents are both heterozygous for freckles. When both parents are heterozygous for a trait, the Punnett square predicts that there is a 25% chance for their children to inherit two recessive alleles and not have freckles. However, in this case, all three of their children do not have freckles.

The actual results deviating from the predicted probability can be attributed to the concept of genetic recombination during meiosis. During meiosis, genetic material from the parents combine and may result in different combinations than what was predicted by the Punnett square. This can lead to variations from the expected outcomes.

Learn more about Heredity and Punnett square