The probability is 1/2. This is because half are likely to be carriers and 1/2 are likely to have hemophilia.
The general term of it all is Cytology, which means the study of the cells. This in turn is split into smaller sciences like Cytophysiology (Study of cell physiology and anatomy), Ctyopathology (Study of diseases effects on cells), and Cytochemistry (study of cell biochemistry).
Sexually because they are part of the animalia kingdom. Sexual reproduction allows genetically diversified offspring, but sexual reproduction requires two animals of the same species.
