Cold Spring Harbor Laboratory
Dna From the Beginning: Sex Linked Hemophilia in the Royal Romanov Family
An animated pedigree clearly explains the way hemophilia was inherited in the Romanov family. Interpreting pedigrees and sex-linked crosses should be much easier to understand after going through this tutorial.
Khan Academy
Khan Academy: X Linked Inheritance
Find out about the chromosomal basis of sex determination, X and Y chromosomes, and X-linkage.
Cold Spring Harbor Laboratory
Dna From the Beginning: Chromosomes Carry Genes
Thomas Hunt Morgan will explain the research he did to determine that some traits are linked to the sex of an individual.
University of Arizona
The Biology Project: Human Biology
This site provides basic information on human genetics and reproduction using tutorials, simulations, images and quizzes. There are also links to other worthwhile sites.