Which of the following is the inner germ layer formed during embryonic development?

• A. Ectoderm
• B. Mesoderm
• C. Endoderm
• D. Periderm

Answer: (C)

Verified step by step guidance

1. Understand the concept of germ layers: During embryonic development, three primary germ layers are formed—ectoderm, mesoderm, and endoderm. These layers give rise to all tissues and organs in the body.
2. Identify the inner germ layer: The endoderm is the innermost germ layer, while the ectoderm is the outermost layer, and the mesoderm lies in between.
3. Learn the role of the endoderm: The endoderm develops into the lining of the digestive tract, respiratory system, and other internal structures such as the liver and pancreas.
4. Differentiate the other options: The ectoderm forms structures like the skin and nervous system, while the mesoderm forms muscles, bones, and the circulatory system. The periderm is not a germ layer but a temporary layer in the development of the skin.
5. Conclude that the correct answer is the endoderm, as it is the inner germ layer formed during embryonic development.