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What is the first organ to develop in the human embryo?
4 Answers
- Anonymous1 decade ago
Part of the answer to your question involves how you define "organ". If you mean "a fully differentiated structural and functional unit in an animal that is specialized for some particular function" that would probably be the placenta, which is actually extraembryonic and supplies developing embryo with nutrients from the mother.
Next would be the heart; there is beating heart tissue by approximately three weeks after fertilization.
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