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.
The basic mollusk characteristics are the presence of an outer shell (except for some species), and a soft body that is bilaterally symmetrical. This article presents some amazing characteristics about the mollusk species.his phylum encompasses some of the highly-diverse animal species in the world. Mollusks are invertebrate animals, meaning that they lack the vertebral column. More information on mollusk characteristics is given in the following paragraphs.