A Reproductive Lexicon


Ownership of this website has been transferred from Northwestern University to Michigan State University.
Please note that some site information may be inaccurate while adjustments to reflect this organizational change are made.

MOOC Advertisement

Learn More:
Get An Introduction to Reproduction

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

Get Started!

egg activation

Egg activation refers to a series of events that occur in the egg after it is fertilized by a sperm. These events include completion of meiosis, initiating the block to polyspermy, and translation of specific mRNAs from the egg that are necessary for embryonic development prior to the maternal to zygotic transition. In all animal species studied to date, a rise in calcium levels within the egg triggers all events of egg activation.