Do cnidarians have radial or bilateral symmetry?
Cnidarians are generally believed to be radially symmetrical animals, but some cnidarians, such as the sea anemone Nematostella, display bilateral symmetry with an oral-aboral axis and a directive axis, which is orthogonal to the oral-aboral axis.
Why do Cnidaria have radial symmetry?
The body parts of a radially symmetrical animal are arranged around a central axis so that each part extends from the center. The animal can be cut along the axis in more than one plane to produce identical halves. Radial symmetry allows them to reach out in all directions. Cnidarians have two tissue layers.
Are cnidarians asymmetrical?
Cnidarians in both groups have an external radial symmetry, yet internal asymmetries and bilaterality are displayed in many groups.
What kind of symmetry do cnidarians have quizlet?
radial symmetry
What type of symmetry do humans have?
bilateral symmetry
What type of symmetry do Ctenophores have?
Ctenophores do not have radial or bilateral symmetry, they have rotational symmetry.
Do Ctenophores have a complete gut?
Ctenophores, one of the most basal branches in the tree of life, have been found to have a through-gut, complete with mouth and anus. Basal animals are surprisingly complex and simplification has been rampant in animal evolution.
Do Ctenophores have hydrostatic skeleton?
Body Covering: Epidermis, collenchyme (contains true muscle cells), Support: Hydrostatic “skeleton”. Digestive System: Digestive cavity open at one end. Animal is a carnivore.
What symmetry do sponges have?
asymmetrical symmetry
Which invertebrates has a mantle and a foot?
Mollusks are a phylum of invertebrate animals defined by their distinct body structure — a head, a visceral mass, a mantle and some kind of foot. The mantle protects the mollusk’s body in place of a skeletal structure, and the “foot” has taken on many adaptions across the mollusca species.
Do all molluscs have a mantle?
All mollusks have a thin layer of tissue called a mantle which covers their internal organs. The mantle produces the mollusk’s shell. Clams, oysters, snails, and octopuses are all mollusks.