In the course of prenatal development of human beings, by the end of the period, the heart begins to beat, the arms and legs become more differentiated, the face starts to form, and the intestinal tract appears.

This occurs by the end of the Embryonic period.

Explanation:

The Embryonic period is the second stage of Prenatal Development. It occurs between the 3rd and 8th week. It is a stage in which the product, now known as an embryo, begins to take a more human-like form.

Some developments include:

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