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Author: Aaron Mullally

This lesson will explain how a zygote develops into an embryo.

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Developing Effective Teams

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Terms to Know

After the morula forms it will implant on the endometrium of the uterus; the blastocyst contains an inner of layers of cells that become the embryo while the outer layer of cells form the placenta.


A stage of development of an individual formed from the inner cell mass of a blastocyst after it has implanted in the uterus.

Inner Cell Mass

A layer of the blastocyst which will develop into an embryo.


The fertilized egg which is the first cell of an individual.