Severe cases can even lead to death. Best way to protect yourself from getting the flu? Get an annual flu shot. When is flu season? The flu season occurs in the fall and winter, but the virus can stay active year-round. Is the flu virus contagious? Yes, it is very contagious. You can have the flu for 1 to 4 days before you start feeling sick.
Some mollusks have bilateral symmetry. Mollusks include gastropods such as snails, bivalves such as oysters, and cephalopods such as squid. Some bivalves have bilateral symmetry. Some mollusks have bilateral symmetry. Mollusks include gastropods such as snails, bivalves such as oysters, and cephalopods such as squid.
Mollusks are members of the phylum mollusca. Mollusks have been evolving in the sea for over 600 million years and there are more than 100 000 mollusks species. The mollusks phylum includes tiny snails, squid, octopus, clams, oysters, abalone, and cuttlefish.They are considered to be the most intelligent of the invertabrate species.he study of mollusks is called malacology. There are four main classes in the phylum mollusca, gastropods, bivalve, cephalopod and Polyplacophora. Gastropods include nudibranches, slugs and snails. They compose over one third of the mollusk group and most are single spiral shells but some have no shells.