Answer:
the spreading of something more widely.
Explanation:
Cells need both genes, and each cell inherits half of the genes from both cell parents.
The number 45 means that the subject has 44 normal autosomal chromosomes (22 chromosomes pairs) plus one (1) good sex chromosome (out of the normal homologous pair). The X0 means that the subject, usually a female, lacks one sister chromosome of the homologous X chromosome pair, or has a partial X sister chromosome.
