Mutations and rearrangements that occur by misalignment during DNA replication are frequent sources of genetic variation in bacteria. Dislocations between a replicating strand and its template at repetitive DNA sequences underlie the mechanism of these genetic events.
Cnidarians take on two basic forms, a medusa and a polyp. The medusa form is a free-swimming structure which consists of an umbrella-shaped body (called a bell), a fringe of tentacles that hang from the edge of the bell, a mouth opening located on the underside of the bell, and a gastrovascular cavity. The mesoglea layer of the medusa body wall is thick and jelly-like.
What is a Cnidarian? cnidarians, such as jelly fish, sea anemones, hydra, and corals, have tentacles surrounding their mouth. they are a hollow-bodied animal with two celled layers that are organized into tissues. the inner layer forms a digestive cavity where food is broken down.A jelly fish.n animal that exists in a mudusa or poylp state. ----------- A cnidarian is defined by the root of its name, cnida, which is Greek for stinging nettle. All cnidarians, therefore, have cnidocytes, which are the stinging, adhering, or entangling cells that allow them to eat, defend, or move.