Final answer:
During embryonic development, gastrulation is the step where the endoderm, mesoderm, and ectoderm germ layers are produced. These layers eventually develop into various structures and systems within the body including internal organs, bones, muscles, and the nervous system. Gastrulation marks a key event in embryogenesis, leading to organogenesis and the formation of a functional organism.
Step-by-step explanation:
Gastrulation is a step during embryonic development when the three germ layers: the endoderm, mesoderm, and ectoderm are produced. Specifically, Option 3: Endoderm, Option 4: Mesoderm, and Option 5: Ectoderm are correct, as these are the layers formed during gastrulation. The endoderm will develop into the internal organs and digestive system, the mesoderm gives rise to structures such as bones, muscles, and heart, and the ectoderm forms the skin and nervous system cells.
During the process of gastrulation, the blastula folds in on itself to form these layers, and this marks a crucial step in the formation of the body plan. These embryonic germ layers are foundational for the subsequent process of organogenesis, which is the development of the organs from these layers. This complex process sets the stage for the rich diversity of tissue types and organ systems that will form within a developing organism.