Embryology

Embryology literally means the study of embryos, the immature organisms contained within the coverings of an egg or within the body of the mother. Embryology is a field of biology that focuses on the development of new individuals from germ cells.

Vertebrate Embryology

Fertilization

Instead of either of the male or female seed components containing a tiny baby, they are each just a cell. When they come together, the new cell, the fertilized egg - swells and changes.

Gastrulation and The Embryonic Period

This zygote divides continually and the cells it becomes dance out a whole extravaganza of movements. The steps of this dance are known to all vertebrates. Whether frog or mouse, human or bird, the dance is nearly the same, right up until the basic form is created. As the cells swirl through their formations, each splits - and they all keep dividing, like the Sorcerer’s apprentice, until there are thousands and then millions and then billions of cells. The dance becomes an extravaganza with whole choruses of cells moving like dancers in a scene from a greatest ballet filmed in an MGM musical with an unlimited budget. Sheets of cells fold and flip to form an intricate tube. Troops of cells disappear to make a crevice, while another multiplying group piles into a bulge. Head to tail, the formations move to bring a shape to the vertebrate embyo.

See also

• Ontogeny
• Embryogenesis
• Recapitulation theory
• Neuroembryology

References

• UNSW Embryology Large resource of information and media

Further reading

• Scott F. Gilbert. Developmental Biology. Sinauer, 2003. ISBN 0-87893-258-5.
• Lewis Wolpert. Principles of Development. Oxford University Press, 2006. ISBN 0-19927-536-X.