Biography:

Mr. Hdeib has a Master degree in Biology (Biotechnology), including the fundamental of molecular biology and modern plant and animal biotechnology, Recombinant DNA technology, cloning, transformation, tissue culture, DNA fingerprinting and other genetic engineering techniques, biodiversity. He graduated from Al Balq'a Applied University Faculty of graduated studies, Department of Biotechnology, Working experience: Lecturer for Genetics Molecular biology for undergraduate students at Al Balq'a Applied University Faculty of graduated studies, Department of Biotechnology. Supervisor for Biology and General Science at the Ministry of Education Jordan Teacher for Biology and General Science at the Ministry of Education Jordan.

Abstract:

Under: Cutting Edge Evolutionary Science. The Evolution of the Cell. THE EVOLUTION: From Molecules to Life

Cells occupy a halfway point in the scale of biological complexity. We study them, on one hand, how they are made from molecules and, on the other, how they cooperate to make an organism as complex as human being. The first cell had to arise from a non-cell; the question is how did it happen?. Living cells probably arose on earth about 3.5 billion years ago by spontaneous reactions between molecules in an environment that was far from chemical equilibrium. From our knowledge of present-day organisms and the molecules they contain, it seems likely that the development of the directly autocatalytic mechanisms fundamental to living systems began with the evolution of families of RNA molecules that could catalyze their own replication. With time, one of these families of cooperating RNA catalysts developed the ability to direct synthesis of polypeptides. Finally, as the accumulation of additional protein catalysts allowed more efficient and complex cells to evolve, the DNA double helix replaced RNA as a more stable molecule for storing the increased amounts of genetic information required by such cells. How did diversity among cells happen? A vast part of Earth's biodiversity is microbial, thus studying single celled organisms is useful for understanding life in general. Cell division is an important property for life, however, there are differences in the mechanisms by which prokaryotes and eukaryotes divide. Bacteria divide by "binary-fission". Eukaryotic cells, on the other hand, divide by different mechanisms: mitosis and meiosis, during these processes replicating of genetic information occurs, in reality, "replication" is not perfect, as there are errors in copying genetic information. These replication errors are partly responsible for genetic variation -- the very "stuff" of evolution. There is also cytoplasmic inheritance (i.e. inheritance of components of the cytoplasm, such as organelles), and this may not necessarily be equally distributed to the daughter cells. Thus, there may also be variations in structural inheritance, which also takes part in evolution. Competition within and between species ("intra-specific competition" and "inter-specific competition", respectively). With replication errors and other sources of variation, individuals may arise with slightly better or slightly different molecular machinery to adapt to changing conditions.