This is a great human, mouse or fish eggs look very similar, around a 1 mm wide, however, each adult in the form of these organisms are widely different in size and appearance. The process of developmental biology is the study of an adult organism into fertilized eggs.
When the egg is fertilized by a single cell which constitutes a complete genome (half from the father and half from the mother), in its genome contains a number of instructions that tell how the single-cell growth and division is growing so that more cells. But then also need new cells from the genome, will tell them what organizations they will eventually develop into additional instructions. They do not want to be the same - if they are our own will be no eyes, ears, or any cell adhesive drop - it will be very inconvenient, to say the least.
Some cells have been told to become a thing, some need to be told to become something else. Understand the genetic instructions of a specific cell selection, and how they are interpreted by them (remember all cells from the beginning had the same instructions on the package bearing) is the basis of developmental genetics.
In its early developmental biology is linked to philosophical accounts of the time regarding the nature of matter. In this sense it is Hippocrates, who explains the development in terms of heat, moisture and freezing. About a century after Aristotle raises the first questions to embryologic development. Its solutions in many fields worked for this thinker would last until late in human thought, when in the seventeenth century to be reevaluated. Aristotle recognized as the first embryologist raises the issue of embryo formation. To do so, meets with two hypotheses. The first commonly called perform, argues that the structures of the embryo is preformed from the beginning and then you are simply enlarged. The second hypothesis proposes that the structures grow progressively over time, this is called epigenesist (epi = on, genesis = beginning) which favored Aristotle correctly. These theories were generated after observing incubated chicken eggs, which also involved primarily the role of the placenta and umbilical cord. Additionally Aristotle made ??observations on the different ways in animals born alive (viviparous) from eggs (oviparity) or by breaking eggs inside the mother (Ovoviviparity). It identified two main patterns of cell division, segmentation and segmentation holoblástica meroblástica. During the medieval period is not recognized so far no progress in this field of science.
The Developmental Biology is the branch of biology that deals with the study of the processes by which organisms grow and develop. Currently, it focuses on studying the genetic control of cell growth, cell differentiation and morphogenesis. The findings made by the Developmental biology can help us understand embryonic malformations (teratogenicity) and chromosomal alterations it suffers moments before his training. Further, understanding how to carry out cellular specialization during embryogenesis may provide information necessary to understand how stem cells specialize in certain tissues and organs, ...