Glands of vertebrates are originated from :-

Options

A. Ectodermal
B. Endodermal
C. Mesodermal
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the origin of glands in vertebrates. It's important to identify the germ layers involved in the development of these glands.

2. **Identifying Germ Layers**: In vertebrates, there are three primary germ layers: ectoderm, mesoderm, and endoderm. Each of these layers contributes to the formation of different tissues and organs in the body, including glands.

3. **Glands from Ectoderm**: The ectoderm is responsible for forming certain glands. Examples include:
- Pituitary gland
- Pineal gland

4. **Glands from Mesoderm**: The mesoderm also contributes to gland formation. An example is:
- Adrenal cortex

5. **Glands from Endoderm**: The endoderm gives rise to several important glands, including:
- Thyroid gland
- Parathyroid glands
- Pancreas
- Thymus

6. **Conclusion**: Since glands in vertebrates originate from all three germ layers (ectoderm, mesoderm, and endoderm), the correct answer to the question is "all of these."

7. **Final Answer**: Glands of vertebrates are originated from: **All of these (ectodermal, endodermal, mesodermal)**.

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