Diploblasts and Cnidarians Lecture Notes

These flashcards cover key vocabulary from the lecture notes on diploblasts and cnidarians, focusing on their definitions and significance in the animal kingdom.

Diploblasts

Organisms that have two embryonic germ layers: ectoderm and endoderm.

Cnidocytes

Specialized cells in cnidarians that contain cnidae, such as nematocysts, used for prey capture and defense.

Mesoglea

A non-cellular middle layer found between the ectoderm and endoderm in diploblastic organisms.

Polyp

One of the two body forms of cnidarians; usually sessile and tubular with a mouth facing upward.

Medusa

The free-swimming form of cnidarians, characterized by its umbrella shape and tentacles.

Cubozoa

Class of cnidarians known as box jellyfish, recognized for their cube-shaped medusae.

Scyphozoa

Class of cnidarians that includes true jellyfish, known for their large medusae.

Anthozoa

Subphylum of cnidarians that includes sea anemones and corals, which lack a medusa stage.

Hydrozoa

Class of cnidarians that can reproduce both asexually and sexually, includes hydras and Portuguese man o'war.

Ectoderm

The outermost of the two primary germ layers in diploblasts, giving rise to the epidermis.

Endoderm

The innermost germ layer in diploblasts, giving rise to the gastroderm.

Cnidae

The specialized organelles in cnidarians, such as nematocysts, used for capturing prey.

Radial symmetry

A body plan in which body parts are arranged around a central axis, characteristic of cnidarians.

Gastrovascular cavity

A central digestive cavity in cnidarians, also involved in circulation.

Asexual reproduction

A mode of reproduction where offspring are produced from a single organism, common in polyps.

Colonial behavior

The ability of some cnidarians to form colonies through asexual reproduction.

Bioluminescent

The ability of some organisms, including ctenophores, to produce and emit light.

Ecosystem

A biological community of interacting organisms and their physical environment.

Planula larva

The free-swimming larval stage of cnidarians that can develop into polyps or medusae.