What does epigenesis suggest about the embryo?

• A. It forms through external environmental factors.
• B. All structures develop from an existing structure in a simple way.
• C. All parts are present in potential form in the egg.
• D. It randomly assembles during gestation.

Answer: (C)

Epigenesis is a biological theory that emphasizes the gradual development of an embryo through a series of steps, leading to the formation of complex structures. The concept suggests that during embryonic development, the various parts of an organism do not pre-exist in a fully formed state but instead emerge progressively from an undifferentiated state.

The idea that "all parts are present in potential form in the egg" aligns with the principles of epigenesis because it acknowledges that while the genetic material contains the instructions for development, the actual structures arise through a process of differentiation, resulting from interactions between genes, cellular environments, and external factors throughout development.

This understanding contrasts with the notion that structures simply develop from existing ones in a straightforward manner or that they randomly assemble during gestation, both of which do not capture the dynamic and interactive nature of embryonic development as proposed by epigenesis. The theory places emphasis on the complexity and ordered progression of development, which supports the notion that an embryo's potential structures are inherently guided by genetic and epigenetic factors rather than being pre-formed.