Heart is

Options

A. Ectodermal
B. Mesodermal
C. Endodermal
D. None of the above.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the origin of the heart in terms of embryonic layers. The options provided are ectodermal, mesodermal, endodermal, and none of the above.

2. **Identifying the Embryonic Layers**: In embryonic development, there are three primary germ layers:
- **Ectoderm**: The outer layer, which develops into structures such as the skin and nervous system.
- **Mesoderm**: The middle layer, which gives rise to various systems including the circulatory system, muscles, and bones.
- **Endoderm**: The innermost layer, which develops into the gastrointestinal tract and associated organs.

3. **Determining the Origin of the Heart**: The heart is a part of the circulatory system, which is derived from the mesoderm. Therefore, the heart originates from the mesodermal layer.

4. **Reviewing the Options**:
- A) Ectodermal: Incorrect, as the heart does not develop from the ectoderm.
- B) Mesodermal: Correct, as the heart originates from the mesoderm.
- C) Endodermal: Incorrect, as the heart does not develop from the endoderm.
- D) None of the above: Incorrect, since the correct answer is option B.

5. **Final Answer**: Based on the analysis, the correct answer is **B) Mesodermal**.

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