Mesoderm produces

Options

A. Brain
B. Heart
C. Urinary b ladder
D. Middle ear.

Answer

To solve the question "Mesoderm produces," we will analyze each option given and determine which one is produced by the mesoderm layer.

### Step-by-Step Solution:

1. **Identify the Germ Layers**:
- The three primary germ layers in embryonic development are ectoderm, mesoderm, and endoderm. Each layer gives rise to different structures in the body.

2. **Analyze Each Option**:
- **Option A: Brain**: The brain develops from the ectoderm. Therefore, this option is incorrect.
- **Option B: Heart**: The heart is derived from the mesoderm. This option is correct.
- **Option C: Urinary Bladder**: The urinary bladder originates from the endoderm. Thus, this option is incorrect.
- **Option D: Middle Ear**: The middle ear also develops from the ectoderm. Therefore, this option is incorrect.

3. **Conclusion**:
- After analyzing all the options, the only structure produced by the mesoderm is the heart. Hence, the correct answer is **Option B: Heart**.

### Final Answer:
The mesoderm produces the heart (Option B).

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