PSY290H5 Chapter Notes - Chapter 9: Neural Tube, Neural Plate, Axon Guidance
Document Summary
A fertilized egg is totipotent that is, the cell has the ability to develop into any class of cell in the body. These new cells are said to be multipotent: most developing cells will eventually become unipotent they can develop into only one type of cell. The development of the neural plate is induced by chemical signals from an area of the underlying mesoderm layer an area consequently referred to as the organizer. Tissue taken from the dorsal mesoderm of the embryo and implanted beneath the ventral ectoderm of another embryo induces the development of an extra neural plate on the ventral surface of the host. Two factors govern migration in the developing neural tube: time and location. In a given region of the tube, subtypes of the neurons arise on a precise and predictable schedule and then migrate together to their prescribed destinations. Many glial cells eventually turn into neurons. Gap junctions between cells are prevalent during brain development.
