Question

Description

Human chromosomes are classified as either autosomes or sex chromosomes, and the inheritance patterns of traits vary depending on the type of chromosome they are located on. Why is this the case?

Instructions

Read Chapter 5 in Essentials of Genetics, then respond to the prompt below:

Prompt:

In humans (and most animals), sex is determined using the X-Y system. The basis of this system is that the number of X chromosomes and Y chromosomes determines whether the individual will be male or female. A male will contain one X and one Y chromosome, while a female will contain two X chromosomes.

For this discussion, consider how the number of X chromosomes affects the inheritance of traits that are carried on the X chromosome. Does this make one sex more likely to display certain characteristics? Why or why not?

Answer 1

1. The chromosomes are of two types. autosomes and sex chromosomes. The sex chromosomes are the chromosomes whose genes are passed from parents to the offsprings. So the inheritance pattern of a trait will always depend on the sex chromosome.

2. In human X chromosome contains hundreds of other genes. Because females have two copies of the X chromosome, whereas males have only one (they are hemizygous), diseases caused by genes on the X chromosome, most of which are X-linked recessive, predominantly affect males.

The X chromosome determines the sex and gives the female characteristics, more the copy number of X, more the character has the female characteristics.