4. Quickly sketch an embryo then label and define anterior, dorsal, ventral and posterior. 5. How do embryos use proteins to identify the different sections?

Explanation:

The term ventral refers to the anterior (front) aspect of the embryo, while dorsal refers to the posterior (back) of the embryo.

Differentiation of cells in the embryo is brought about by both internal cellular factors as well as extracellular factors that act on the cell from the outside. A collection of physiological mechanisms guide cells to it particular pathway during development. This is made possible by the cell’s natural ability to control what genes are expressed and translated into proteins. Every cell contains DNA within the nucleus, which holds the blueprint to build different proteins in the cell. Different signals can cause embryonic cells to select specific parts of the DNA which can then be used to synthesize proteins, eventually building different cell types.