One issue is to which President or Congress a particular year's deficit should be attributed. U.S. Congressional terms start on Jan. 1, Presidential terms later in January, and the fiscal year on Oct. 1, so none of them exactly match up.
These nephridia, which are called protonephridia, are branched tubules of ectodermal origin. They are closed at the internal ends by terminal cells, or solenocytes, and open to the exterior by means of excretory pores, or nephridiopores.
Helminth Parasites. The word âhelminthâ is a general term meaning âwormâ, but there are many different types of worms. Prefixes are therefore used to designate types: platy-helminths for flat-worms and nemat-helminths for round-worms.All helminths are multicellular eukaryotic invertebrates with tube-like or flattened bodies exhibiting bilateral symmetry.any helminths are free-living organisms in aquatic and terrestrial environments whereas others occur as parasites in most animals and some plants. Parasitic helminths are an almost universal feature of vertebrate animals; most species have worms in them somewhere.