When a sperm cell with an X-chromosome fertilizes an egg, what is the sex of the offspring?

When a sperm cell carrying an X-chromosome fertilizes an egg, the resulting genotype of the offspring will be XX, which is characteristic of females. In mammals, including humans, the sex of the offspring is determined by the combination of sex chromosomes inherited from the parents.

In this case, the egg always contributes an X-chromosome, and when it is fertilized by a sperm carrying an X-chromosome, both contribute an X chromosome, leading to a female offspring. This process is part of the fundamental principles of genetics, particularly the inheritance of sex-linked traits. Understanding this mechanism is essential for studying reproduction and genetics in livestock and other animals.