Office of Training & Education 2. Â§1926.450 - SUBPART L. âUpdates the existing standard to include types of. scaffolds such as catenary and step and trestle. âAllows flexibility in the use of fall protection. systems to protect employees. âSimplifies language, eliminates duplicative, outdated provisions, consolidates overlapping. requirements.
Two whole shells, one closed and one open, of the marine bivalve Abra alba. Live marine venerid cockles, Austrovenus stutchburyi from New Zealand. A bivalve shell is part of the body, the exoskeleton or shell, of a bivalve mollusk.In life, the shell of this class of mollusks is composed of two hinged parts or valves. Bivalves are very common in essentially all aquatic locales, including saltwater, brackish water, and freshwater.wo whole shells, one closed and one open, of the marine bivalve Abra alba. Live marine venerid cockles, Austrovenus stutchburyi from New Zealand. A bivalve shell is part of the body, the exoskeleton or shell, of a bivalve mollusk.
Gastropods. About 70 percent of mollusk species are gastropods. Common gastropods include snails, abalones, sea cucumbers and slugs. They all move by rippling the muscles in their stomach foot, which is what gastropod means.ivalves. Clams, limpets, mussels, oysters and scallops are the most common types of bivalves, which also are mollusks. Bivalve means two shells, which is what these creatures have instead of a bone structure. Bivalves are filter feeders.