http://www.physorg.com/ en-us Physorg.com internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine. A key item in the developmental agenda of a plant leaf is the establishment of an axis that makes a leaf's top half distinct from its bottom half. This asymmetry is crucial for the leaf's function: it ensures that the leaf develops a flattened blade that is optimized for photosynthesis, with a top surface specialized for light harvesting and a bottom surface containing tiny pores that serve as locales for gas exchange. http://www.physorg.com/news155132111.html Biology Sun, 01 Mar 2009 12:15:57 EST news155132111 Plant cells communicate via microscopic channels called plasmodesmata that are embedded in their cell walls. For the stem cells in the plants' growing tips, called "meristems," the plasmodesmata are lifelines, allowing nutrients and genetic instructions for growth to flow in. http://www.physorg.com/news154101168.html Biology Tue, 17 Feb 2009 13:53:14 EST news154101168 In plant pollen grains, sperm cells, which carry the genetic material to be passed on to progeny, are cocooned within larger "companion" cells that are called pollen vegetative cells. These companions provide sperm with energy and nourishment, and push them towards their targets during fertilization. http://www.physorg.com/news153064281.html Biology Thu, 05 Feb 2009 13:51:37 EST news153064281 Two molecular biologists at Cold Spring Harbor Laboratory have uncovered important new details about how a gene mutation causes a cellular editing error that results in a devastating disease called pontocerebellar hypoplasia (PCH). The new findings were published online, ahead of print, on January 25th in the journal Nature Structural and Molecular Biology. http://www.physorg.com/news152373171.html Biology Wed, 28 Jan 2009 13:55:59 EST news152373171 Researchers at Cold Spring Harbor Laboratory (CSHL) announced today the discovery of a new class of small RNAs. At the same time, they reported that their discovery suggests the presence of a strikingly novel biochemical pathway for RNA processing in which these and possibly other small RNAs are produced. The research, which is part of a multinational project called ENCODE, also provided information concerning the biological function of the new short RNA class. http://www.physorg.com/news152211180.html Biology Mon, 26 Jan 2009 17:04:05 EST news152211180 How can moss help us to treat Alzheimer's disease? What can the lamprey immune system tell us about evolution? Can genetic studies of snapdragon populations help with efforts to conserve rare species? What can quail teach us about human aging, reproduction, and hereditary diseases? Will studies of choanoflagellates unravel the origins of animals? http://www.physorg.com/news146491986.html Biology Fri, 21 Nov 2008 12:13:06 EST news146491986 For the first time, a new edition of a major textbook will be simultaneously released in print and free online in a novel approach to publishing that permits the textbook to reach a wider audience. http://www.physorg.com/news143373479.html Biology Thu, 16 Oct 2008 10:57:59 EST news143373479 A variety of organisms -from bacteria and fungi to plants and animals -have biological rhythms, where the timing and duration of fundamental biological processes is naturally adjusted to allow them to adapt and survive, even under fluctuating environmental conditions. In recent years, significant advances have been made to understand the molecular basis of these rhythms and how they translate into modifications in cellular physiology and organismal behavior. http://www.physorg.com/news139743481.html Biology Thu, 04 Sep 2008 10:38:01 EST news139743481