A colossal and unusually symmetric cloud ring was captured by NASA’s Terra satellite hovering alone in the central Pacific ...

Eventually, enzymes for the synthesis of membranes and cell walls evolved, resulting in the formation of cells. Viruses, then, may have existed before bacteria, archaea, or eukaryotes (Figure 4 ...

According to Schleiden, however, the first phase of the generation of cells was the formation of a nucleus of "crystallization" within the intracellular substance (which he called the "cytoblast ...

By injecting a molecule that blocks the Shh signaling pathway on the 9th day of embryonic development -- just before feather buds appear on the wings -- the two researchers observed the formation ...

The widths of the lines show occasional as well as longer term changes of a few percent but no evidence for giant convection cells. These spectroscopic observations are more consistent with a ...