Many genotypic and phenotypic characteristics are linked to the X chromosome. Some of these are caused by X-linked traits, whereas others are due to X chromosome inactivation. Drag the labels on the left to the appropriate category on the right. Calico cats have patches of black and orange fur X inactivation X-linked Color blindness is more common in men "Heterozygotes" can express the recessive phenotype Hemophilia Rett syndrome is not always fatal in females Barr bodies

X chromosome inactivation:

- Calico cats have patches of black and orange fur

- "Heterozygotes" can express the recessive phenotype

- Rett syndrome is not always fatal in females  

- Barr bodies

X linked traits:

- Color blindness is more common in men  

- Hemophilia  

Explanation:

X chromosome inactivation refers to the mechanism in which one X chromosome is randomly inactivated during early embryonic development in female mammals. The inactivated (silenced) X chromosome is condensed into a structure called Barr body. In cats, the gene encoding for the orange/non-orange fur coloring is X-linked, thereby X inactivation explains why most calico cats (i.e., those cats that have a color pattern with orange and black spots) are female. Moreover, Rett syndrome is a neurodevelopmental disorder caused by a mutation in the X-linked MECP2 gene, and therefore this disorder is much more serious in males. On the other hand, color blindness is more common in men because males have only one X chromosome. In the same way, hemophilia, which is a disorder caused due by a mutation in one gene required for synthesizing one clotting factor, is more common in males than in females because the gene responsible for this disorder is located on the X chromosome.

unicellular organisms, like bacteria, are able to perform all life functions within one single cell. multicellular organisms need many different types of cells to carry out the same life processes. each of these special types of cells has a different structure that it perform a specific function.