Following fertilization, the single celled embryo undergoes a number of mitotic divisions to produce a ball of cells called a blastula or blastoderm. Although these cells are all genetically identical, they gradually begin to express different gene products that reflect the regions of the adult body they will form. In my first lecture I discuss how these initial patterns of gene expression arise. In Drosophila, a maternally supplied transcription factor called Bicoid plays a particularly important role. Bcd RNA is anchored at the anterior end of the egg but is …

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Stem cells are cell with remarkable ability to develop into many different cell types in the body and also can self renew to produce more stem cells. In other words when a stem cell divide it can either form a specialized cell ( differentiation ) , such as a blood cell, a Heart cell a brain cell or can remain as a stem cell.
Two important features like indefinite ability to divide to form a specialized cell and self renewal, differentiates a stem cell from any other …

Recent work done in the lab of Eric olson in colloboration with Dr Hesham Sadek has shown significant similarities in the way young mice and fishes regenerate lost cardiac cells after an injury.
As time pass by cells die, we tend to lose cells and loss of cells could be bcoz of aging , physical or ischemic injury, Toxication or chemotherapy and due to any of the degenerative diseases. However organs tend to make up for lost cells to regain normal function and this regneration process can be again be achieved …