Evolution and systematics

Lophogastrids appear to be most closely allied to the strictly fossil pygocephalomorphs; indeed, species recognizable as lophogastrid relatives are known from the Pennsyl-vanian Period, about 325-286 million years ago. In these groups the sternites (ventral shields) are wide, with the thoracic legs being located on the outer edges of the somites.

The order Lophogastrida contains two extant families, the Lophogastridae with six genera, and the Eucopiidae with the single genus Eucopia. Many scientists now regard lophogastrids as a suborder of the order Mysidacea. They differ from the other mysid suborder in having gills on most thoracic appendages; no statocyst (organ governing the sense of balance) in the uropod; and no modifications of the anterior pleopods in the males. Some authors have suggested that any resemblance to other mysids is purely superficial and that the lophogastrids should have their own order. The latter classification is followed here.

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Diabetes 2

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Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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