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## What is the probability of the parents having a child that is heterozygous?

The chance of either parent being a heterozygote is 1/4, as calculated above. Then, the probability that both parents are heterozygotes, and the probability that two heterozygotes will have a heterozygous child, is 1/4 x 1/4 x 1/2 = **1/32**.

## What is the probability that two parents heterozygous for a particular trait will have a child that is homozygous recessive for that trait?

If both parents carry only one copy of a recessive gene, the likelihood of a child bearing the recessive trait is one in four. The probability rises to **two in four** if one parent is homozygous recessive for the gene — for example, ww — and the other parent is heterozygous.

## What is the probability of two heterozygous parents having a child with a homozygous recessive genotype?

If a heterozygous person has children with a normal (homozygous recessive) person, each child has a **50% chance** of inheriting the disease.

## When a child is heterozygous for a trait?

When you’re heterozygous for a specific gene, it means **you have two different versions of that gene**. The dominant form can completely mask the recessive one, or they can blend together. In some cases, both versions appear at the same time. The two different genes can interact in various ways.

## How do you find the percentage of heterozygous?

The percentage of heterozygous individuals (carriers) in the population. Answer: Since 2pq equals the frequency of heterozygotes or carriers, then the equation will be as follows: 2pq = (2)(.

…

- The frequency of the recessive allele. …
- The frequency of the dominant allele. …
- The frequency of heterozygous individuals.

## What is the probability of the parents having a child that is homozygous for this trait?

There is a 50% chance that the children will be heterozygous (Aa) and a **25% chance** that they will be homozygous dominant (AA). Children with either of these genotypes will have this trait expressed in their phenotypes.

## What happens if both parents are heterozygous?

If both parents are heterozygous (Ww), there is **a 75% chance that any one of their offspring will have a widow’s peak** (see figure). A Punnett square can be used to determine all possible genotypic combinations in the parents.

## What is the chance that a heterozygous parent passes on a recessive allele?

A person with a single gene disorder has a 50/50 chance of passing the mutated allele to a child who will become a carrier. If both parents have a heterozygous recessive mutation, their children will have **a one-in-four chance** of developing the disorder. The risk will be the same for every birth.

## What is the probability that both recessive genes will be contributed to the child for a specific trait?

However, they can pass the abnormal gene to their children. If you are born to parents who both carry the same autosomal recessive gene, you have a **1 in 4 chance** of inheriting the abnormal gene from both parents and developing the disease. You have a 50% (1 in 2) chance of inheriting one abnormal gene.

## What is the phenotypic ratio for the offspring of the two parents who are both heterozygous for PKU?

If they are both heterozygous, then one-quarter of their children would have PKU, so the probability that their first child will have PKU is 1/4, and the probability of their being heterozygous and of their first child having PKU is 4/9 × 1/4 = 4/36 = **1/9**, which is the answer to the question.

## When an individual heterozygous for a trait is crossed with an individual homozygous recessive for the trait the offspring produced will?

Mendelian Genetics

Question | Answer |
---|---|

When an individual heterozygous for a trait is crossed with an individual homozygous recessive for the trait, the offspring produced will? | All have the same genotype |

If a characteristic is sex-linked, the gene for it is found on? | A Sex chromosome |