Human heart develops from embryonic :

Options

A. ectoderm
B. mesoderm
C. endoderm
D. all of these

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks from which embryonic layer the human heart develops.

2. **Understand the Embryonic Layers**: There are three primary germ layers in the embryo:
- Ectoderm (outer layer)
- Mesoderm (middle layer)
- Endoderm (inner layer)

3. **Determine the Function of Each Layer**:
- Ectoderm primarily forms the skin and nervous system.
- Endoderm forms internal organs such as the digestive tract and respiratory system.
- Mesoderm is responsible for forming the heart, muscles, and skeleton.

4. **Identify the Correct Layer for Heart Development**: The human heart is known to develop from the mesoderm, which is the middle layer of the embryo.

5. **Timing of Heart Development**: The heart begins to form around 18 to 19 days after fertilization and is the first functional organ to develop in the embryo.

6. **Conclusion**: Therefore, the correct answer to the question is that the human heart develops from the mesoderm.

**Final Answer**: The human heart develops from the embryonic mesoderm.

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