During embryonic development , endoskeleton and muscle develop from which germinal layer :
(a) Ectoderm
(b) Endoderm
(c) Mesoderm
(d) Blastopore

Options

A. Ectoderm
B. Endoderm
C. Mesoderm
D. Blastopore

Answer

To determine which germinal layer gives rise to the endoskeleton and muscles during embryonic development, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Germ Layers**:
- During embryonic development, there are three primary germ layers: ectoderm, mesoderm, and endoderm.
- Ectoderm is the outer layer, mesoderm is the middle layer, and endoderm is the inner layer.

2. **Analyze the Options**:
- **Option A: Ectoderm**: This layer primarily develops into the skin and nervous system. It does not contribute to the formation of muscles or the endoskeleton.
- **Option B: Endoderm**: This layer forms the lining of the digestive tract and some organs. It is not responsible for developing muscles or the endoskeleton.
- **Option C: Mesoderm**: This middle layer is crucial for the development of muscles, bones, and various connective tissues. It is responsible for forming the endoskeleton.
- **Option D: Blastopore**: This is not a germ layer but an opening that forms during early embryonic development. It can develop into either the mouth or anus but does not contribute to muscle or endoskeleton formation.

3. **Conclusion**:
- Since the mesoderm is responsible for the development of muscles and the endoskeleton, the correct answer is **(c) Mesoderm**.

### Final Answer:
(c) Mesoderm