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Describe the stages of cellular development prior to tissue stages. Your response should be approximately one paragraph in length and include the key words: cleavage, morula, blastula, blastocoel.

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Answer:

Morula (cleavage stage) >> blastoderm (blastula surrounded by the blastocoel)

Step-by-step explanation:

The morula is an early-stage embryo stage (3 to 4 days after fertilization). During this stage, the embryo is composed of a globular solid mass of 16 to 32 cells (i.e., blastomeres) that are formed by cleavage of the zygote. The morula stage precedes the blastocyst stage (4 to 5 days after fertilization), a distinctive stage of a mammalian embryo with over 100 cells. In the rest of the animals, it is referred to as a blastula. A blastoderm is a post-cleavage embryo consisting of a solid layer of epithelial tissue that makes up the blastula, which surrounds a fluid-filled cavity called the blastocoel.

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