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The Morula and Blastocyst

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Script: By 3 to 4 days after fertilization, the dividing cells of the embryo assume a spherical shape and the embryo is called a morula.

By 4 to 5 days, a cavity forms within this ball of cells and the embryo is then called a blastocyst.

The cells inside the blastocyst are called the inner cell mass and give rise to the head, body, and other structures vital to the developing human.

All ages referenced to fertilization, not last menstrual period.

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The Morula and Blastocyst
( 5 days)

Amnion and Germ Layers
( 7 days)

The Folding of the Embryo
( 3 weeks)

The Heart in Action
( 4 weeks, 4 days)

Hand Plates and Cartilage
( 5 weeks, 6 days)

Hand Movement
( 6 weeks, 6 days)