Question

In humans, having two eyebrows is a completely dominant trait. The recessive trait is

expressed as having a single connected eyebrow. If a two parents who are heterozygous for
the eyebrow trait had an offspring, what is the probability that their child would express the
dominant phenotype?
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Answer 1

The probability that the offspring of two heterozygous parents will express the dominant phenotype of having two separate eyebrows is 75%.

Step-by-step explanation:

In humans, having two eyebrows is a dominant trait, while having a single connected eyebrow is the recessive trait. If two parents are heterozygous for the eyebrow trait and we represent the dominant allele for two eyebrows as 'E' and the recessive allele for a connected eyebrow as 'e', each parent's genotype is Ee. When these parents conceive a child, the probability that the offspring expresses the dominant phenotype of two eyebrows can be determined using a Punnett square.

A Punnett square is a diagram that is used to predict an outcome of a particular cross or breeding experiment. It shows how the alleles from each parent combine and what genotypes and phenotypes can be expected in their offspring. In this case, when we cross two heterozygous parents (Ee x Ee), the potential genotypes of the offspring are EE (homozygous dominant), Ee (heterozygous), and ee (homozygous recessive).

The possible combinations and their corresponding probabilities are as follows:

1/4 chance of being homozygous dominant (EE)

1/2 chance of being heterozygous (Ee)

1/4 chance of being homozygous recessive (ee)

Since both the homozygous dominant (EE) and heterozygous (Ee) genotypes result in the dominant phenotype of having two eyebrows, we add their probabilities together to determine the overall chance of expressing the dominant phenotype:

1/4 (EE) + 1/2 (Ee) = 3/4 or 75%

Therefore, there is a 75% probability that the offspring of two heterozygous parents will express the dominant phenotype of having two separate eyebrows.

Answer 2

The baby would most likely carry that trait

Explanation

The chances of the child to be similar in a way could happen or not. The probability rate wouldn't be close to either parent even thought most of the time the child takes after the mother.