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.
Molluscs and annelids also share a eucoelomate body cavity; i,e,. the coelom is completely lined with mesoderm tissue. A major difference between them is that annelids are segmented and have a closed circulatory system whereas molluscs are not segmented and have an open circulatory system.Phylum: Mollusca - [soft body] snails, bivalves, squid and octopi. Molluscs are a diverse group with over 50,000 described species.nnelids are characterized by having elongate, conspicuously segmented body. Unlike the molluscs with their reduced coelom, annelids have a large coelom that is divided by septa between individual segments. Extreme segmentation believed to be an adaptation for burrowing in soil.