Hemophilia is a recessive sex-linked disorder (Xh). A man with hemophilia and a female carrier are concerned about their daughter inheriting the disorder. Use a punnett square explain to these parents the probability (percent chance) that their daughter could have the disorder.

The chances of a hemophilic man and a female carrier having a that one of their daughters inherits the disease are 25%.

Explanation:

Since hemophilia is a disease with a sex-linked recessive inheritance pattern —X chromosome— all males who acquire the altered gene will have hemophilia (Y), while a female should have both altered chromosomes (X) to manifest the disease.

If a hemophilic male and a female carrier of the hemophilia gene have children, the possibility of having a daughter with hemophilia can be seen by crossing.

Alleles                      Y

                   Y

X              X            XY

In the offspring, there are:

The hemophilic man and the carrier woman should know that they have a 25% chance of having a hemophilic daughter, or that 50% of their daughters may have the disease.

measuring light intensity

light meters can be used to measure light intensity. the meter is held at the soil surface and pointed in the direction of the maximum light intensity, and then the meter is read.

errors can be made when measuring light intensity by accidentally shading the light meter. the reliability of the results can be checked by taking many samples.