Escherichia coli (commonly abbreviated E. coli) is a Gram-negative, rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms (endotherms).Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans.The harmless strains are part of the normal flora of the gut, and can benefit their hosts by producing vitamin K2, and by preventing the establishment of pathogenic bacteria within the intestine.ost E. coli strains are harmless, but some serotypes can cause serious food poisoning in humans. The harmless strains are part of the normal flora of the gut, and can benefit their hosts by producing vitamin K2, and by preventing the establishment of pathogenic bacteria within the intestine.
In flowering plants the gametophytes are very reduced in size, and are represented by the pollen and the embryo sac. The sporophyte produces spores (hence the name) by meiosis, a process also known as reduction division that reduces the number of chromosomes in each spore mother cell by half.The resulting meiospores develop into a gametophyte.n flowering plants the gametophytes are very reduced in size, and are represented by the pollen and the embryo sac. The sporophyte produces spores (hence the name) by meiosis, a process also known as reduction division that reduces the number of chromosomes in each spore mother cell by half.
Unlike animals, the diploid stage (the one with two sets of chromosomes) in plants does not produce gametes. Rather, this stage produces spores via meiosis and is therefore known as the sporophyte (spore-producing plant).The sporophyte is the stage most familar to us, as seen in the following image.nlike animals, the diploid stage (the one with two sets of chromosomes) in plants does not produce gametes. Rather, this stage produces spores via meiosis and is therefore known as the sporophyte (spore-producing plant). The sporophyte is the stage most familar to us, as seen in the following image.