I would like you to review the scheme of the formation of the complex of axial organs in lancelets. Draw the stage

The scheme of the formation of the complex of axial organs in lancelets can be explained as follows:

1. During embryonic development, lancelets undergo a process known as gastrulation, which begins with the formation of the blastula.

2. The blastula then undergoes invagination, which is the folding inward of one side of the blastula to form a structure called the gastrula.

3. In the gastrula, three germ layers are formed: the ectoderm, mesoderm, and endoderm. These germ layers give rise to different tissues and organs in the organism.

4. The notochord, one of the key axial organs in lancelets, is formed from the mesoderm. The notochord develops along the dorsal side of the embryo and serves as a support structure. It also plays a role in determining the axial orientation of the developing embryo.

5. The intestinal tube, which forms the digestive system, is derived from the endoderm. It develops from a region of the gastrula called the archenteron. The archenteron eventually becomes the gut or digestive tract of the organism.

6. The nerve tube, also known as the neural tube, is formed from the ectoderm. It develops along the dorsal side of the embryo, just above the notochord. The neural tube gives rise to the central nervous system, including the brain and spinal cord.

To represent the stage of formation of axial organs in lancelets, we can draw a schematic diagram as follows:

[Diagram]

In the diagram, we can label the notochord, intestinal tube, and nerve tube at their respective positions. Additionally, it would be helpful to include labels for the germ layers (ectoderm, mesoderm, and endoderm) to indicate their role in the formation of these organs.

By understanding the process of embryonic development and the formation of these axial organs, students can gain a comprehensive understanding of the complex biological processes that occur during lancelet development.