Describe the function and components of the mucosal barrier of the stomach. Protects the stomach from autodigestion Components Thick coating of bicarbonate-rich mucus Tight junctions of the epithelial cells Plasma membrane of gastric glands are impermeable to HCl.
World Range & Habitat. Sea lampreys, Petromyzon marinus, are found only in the Mediterranean and North Atlantic, in the coastal seas off the North East USA, Nova Scotia, southern Greenland, the UK, Ireland and Scandinavia. They are also found in the Great Lakes and enters inland freshwater rivers and streams to breed.
Annelids are found worldwide in all types of habitats, especially oceanic waters, fresh waters, and damp soils. Most polychaetes live in the ocean, where they either float, burrow, wander on the bottom, or live in tubes they construct; their colours range from brilliant to dull, and some species can produce light.