Cnidarians and Ctenophores Review

These flashcards cover key concepts related to Cnidarians and Ctenophores, focusing on their anatomy, life cycles, ecological roles, and relationships.

What type of symmetry do phylum Cnidaria typically exhibit?

Primary radial symmetry or biradial symmetry.

What specialized cells do Cnidarians have that contain stinging organelles?

Cnidocytes.

What are the two main body types of Cnidarians?

Free-swimming medusae and sessile polyps.

What is the term for the extracellular matrix found in Cnidarians?

Mesoglea.

Name the four traditionally recognized classes of Cnidarians.

Hydrozoa, Scyphozoa, Cubozoa, and Anthozoa.

What ecological role do reef-building corals provide?

They provide food and economic value, with 25% of marine life depending on reefs.

What body plan do polyps have?

Tubular body with the mouth directed upward, surrounded by tentacles.

How do colonial polyps differ from solitary polyps?

Colonial polyps may have specialized functions such as feeding, reproduction, or defense.

What characteristic is unique to the class Staurozoa?

They lack a medusa stage and have a solitary, stalked body.

Describe the digestive process in Scyphozoans.

They catch prey with tentacles and use their gastrovascular cavity to digest it with enzymes.

What defines the class Cubozoa?

The medusa form is dominant, and the polyp stage is tiny.

What is the significance of Cnidarian mutualism with Zooxanthellae?

The algae provide nutrients to the corals, while the corals offer a habitat.

What happens to corals under environmental stress?

They may experience bleaching, losing their symbiotic algae.

How do Ctenophores primarily move?

Using eight rows of comb-like plates of cilia.

What type of cells do Ctenophores use to capture food?

Epidermal glue cells called colloblasts.

What type of reproductive strategy can some anemones exhibit?

They can reproduce asexually by processes including budding and pedal laceration.

What is a defining feature of pelagic hydroids?

They typically have a polyp stage and a free-swimming medusa stage.

What is the role of the gastrovascular cavity in Cnidarians?

It acts as the stomach, aiding in the capture and digestion of prey.

What do hydrozoans primarily consist of?

Most are marine and colonial, having both polyp and medusa forms.