Secretion is the process of elaborating, releasing, and oozing chemicals, or a secreted chemical substance from a cell or gland.In contrast to excretion, the substance may have a certain function, rather than being a waste product.ecretion is the process of elaborating, releasing, and oozing chemicals, or a secreted chemical substance from a cell or gland.
The oldest shark fossils. The oldest fossilized evidence of prehistoric sharks comes from shark-like scales that date to 455 million years ago during the Ordovician Period, in Colorado. Some paleontologists do not agree that these scales are sufficiently shark-like to pronounce them sharks.
Dragon's teeth. Dragon's teeth or dragon's tooth first appeared in Greek mythology; once planted, each tooth grew into a fully armed warrior. This gave rise to the phrase to sow dragon's teeth, used as a metaphor to refer to doing something that has the effect of fomenting disputes. Later uses of the term are: 1  Dragon's teeth (fortification), anti-tank obstacles. 2  Dragon's Teeth: A Novel, an 1878 realist novel.  The Dragon's Teeth, a 1939 mystery novel.