MOOC Advertisement

Learn More:
Get An Introduction to Reproduction

Learn more about the the science of reproduction. Dr. Teresa Woodruff, creator of Repropedia, is offering a free online course exploring the world of reproduction.

Get Started!


Hyperploidy is a state in which cells contain one or more extra chromosomes. Humans normally have 46 chromosomes per cell, but if a human has 47 or more chromosomes per cell, then that person is hyperploid. Trisomy 21 (commonly called Down Syndrome) is one example of hyperploidy because there are three copies of chromosome 21.