15.2: Sponges and Cnidarians - Biology LibreTexts
2021年9月23日 · Animals included in phylum Porifera are parazoans and do not possess true tissues. These organisms show a simple organization. Sponges have multiple cell types that are geared toward executing various metabolic functions. Cnidarians have outer and inner tissue layers sandwiching a noncellular mesoglea.
Basal Animals: Poriferans and Cnidarians – College Biology II …
Sponges, or poriferans, are almost unique in being animals that do not possess true tissue. However, they do have cell types that perform specialized functions. The reason that we do not call these tissues is that sponge embryos do not undergo gastrulation during development.
15.2 Sponges and Cnidarians - Concepts of Biology - OpenStax
Sponges are similar to what might have been the ancestor of animals: colonial, flagellated protists. The cnidarians, or the jellyfish and their kin, are the simplest animal group that displays true tissues, although they possess only two tissue layers.
15.2 Sponges and Cnidarians – Concepts of Zoology – Hawaiʻi …
Cnidarians represent a more complex level of organization than Porifera. They possess outer and inner tissue layers that sandwich a noncellular mesoglea between them. Cnidarians possess a well-formed digestive system and carry out extracellular digestion in a digestive cavity that extends through much of the animal.
Phylum Cnidaria | OpenStax Biology 2e - Lumen Learning
Compare structural and organization characteristics of Porifera and Cnidaria; Describe the progressive development of tissues and their relevance to animal complexity; Identify the two general body forms found in the Cnidaria; Describe the …
Sponges (Porifera) do not have distinct tissues-- their whole body is organized as a single tissue. All other animals have distinct tissues that initially develop in separate layers. With the exception of the phylum Porifera (sponges), all animals have …
9: Porifera and Cnidaria - Biology LibreTexts
9.2: Phylum Porifera 9.3: Phylum Cnidaria 9: Porifera and Cnidaria is shared under a CC BY 4.0 license and was authored, remixed, and/or curated by LibreTexts.
Porifera, Cnidaria, and Ctenophora are the most primitive clade of metazoans. They distinguish themselves from the other metazoans by their lack of bilateral symmetry. Inside their clade, each phylum is clearly distinguished by its general features. Porifera have a cellular, rather than tissular, level of organization, without any true nervous or
Porifera, Echinodermata, and Cnidaria - Animal Classification
Poriferans, Echinoderms, and Cnidarians live in the water. Poriferans (phylum Porifera) are sponges. These aquatic, asymmetrial animals are also sessile (unlike most animals). They are simple creatures, having no tissues. They can reproduce sexually or …
Phylum Porifera and Cnidaria - SpringerLink
2016年2月2日 · The main features to recognize members of Porifera (sponges) and Cnidaria (corals, sea anemones, jellyfish) are presented. Some toxinological information is highlighted focusing on dangerous species like sea anemones and box jellyfish.