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.
The chestnut and silver lamprey are parasitic in their adult stage and feed on body fluids and blood of fish. They can leave a deep wound in the fish that they feed on but rarely kill the host fish as the sea lamprey does. The American brook and the northern brook lamprey are not parasitic on fish and do not feed in their adult life stage. The invasive sea lamprey is the largest of the lamprey in the Great Lakes and can attain a size of two feet. The two native parasitic chestnut and silver lamprey can reach a size of one foot. The two native non-parasitic American brook and northern brook lamprey reach a maximum size of about six inches.