Organogenesis

• When does the organogenesis in the frog begins?

  When the cells of the most dorsal region of the mesoderm condense to form a rod of cells called the notochord.
• The notochord cells produce chemical signals that redirect the fate of the ectodermal cells above it. What is the redirection that happens?

  Instead of forming epidermis, the cells above the notochord are instructed to become the cells of the nervous system. T
• At this stage, the embryo is called a neurula in which the cells change their shapes and rise up from the round body.
• What happens when the neural precursor cells elongate, stretch, and fold into the embryo?

  It forms the neural tube.
• It covers the neural tube.

  The future epidermal cells of the back.
• Explain what happens during organogenesis : neurulation.

  It start when cells of the most dorsal region of mesoderm condense to form a rod of cells called notochord. Notochord cells form chemical signals to redirect the fate of ectodermal cells above it to not form epidermis. The cells above the notochord become the nervous system cells. The cells change shapes, rise up from the round body. The embryo now becomes the neurula. The neural precursor cells elongate, stretch, fold and form a neural tube. The future epidermal cells of the back cover the neural tube.
• It covers the neural tube.

  The future epidermal cells of the back.