Contents
What do the Cnidaria and the ctenophora have in common?
Similarities Between Cnidaria and Ctenophora Both Cnidaria and Ctenophora consist of coelenterate animals with a hollow gut. Both Cnidaria and Ctenophora contain a mouth, which is surrounded by tentacles. Both cnidarians and ctenophores are diploblastic animals. Both cnidarians and ctenophores contain mobile organisms.
What are ctenophores related to?
Ctenophores have been classified as eumetazoans, often as the sister group of the cnidarians, but also as the sister group of the bilaterians.
What are Colloblast and what purpose do they serve for the ctenophores compare this to the cnidarians?
Colloblasts are unique, multicellular structures found in ctenophores. Like the cnidocytes of cnidarians, colloblasts are discharged from the animals’ tentacles, and are used to capture prey. However, unlike cnidocytes, which are venomous cells, colloblasts contain adhesives which stick to, rather than sting the prey.
What are 3 characteristics of ctenophores?
The general Characteristics of the Phylum Ctenophora are:
- Biradially symmetrical, with an oral – aboral body axis .
- Eight rows of ciliated “combs” or ctenes , controlled by an apical sense organ at the aboral pole.
- Incomplete gut (mouth but no anus ).
- No excretory, respiratory, or circulatory systems.
What are the similarities and differences between cnidarians and Ctenophora?
Both cnidarians and ctenophores are diploblastic animals. Cnidarians exhibit radial symmetry whereas ctenophores exhibit biradial symmetry. Both contain tentacles, surrounding their mouth. The main difference between cnidarians and ctenophores is their body symmetry.
Why do ctenophores resemble jellyfish?
Ctenophores, usually known as “comb jellies” may closely resemble jellyfish, but they form a completely distinct category. In Greek, their name means “comb bearer” (ktenos: comb, phoros: to carry). Why? Because they have 8 vertical strips bearing thousands of comb-like cilia running the length of their body.
What distinguishes cnidarians and ctenophores from being triploblastic?
They might be labeled as triploblastic animals due to the following reasons: Both cnidarians and ctenophores have a gelatinous middle layer surrounded by epidermis and internal gut lining. This body is diploblastic, but the presence of cells within the middle gelatinous layer is problematic.
Does Cnidaria have radial symmetry?
Both cnidarians and ctenophores now show various forms of symmetry in planes passing along the oral-aboral axis (Fig. 1). In some cnidarians, this takes the form of multiple planes of mirror symmetry, hence the moniker “radial symmetry”.
Why are phylum ctenophora classified separately from phylum Cnidaria?
Modern authorities, however, have separated the cnidarians and ctenophores on the basis of the following ctenophore characteristics: (1) the lack of the stinging cells (nematocysts) that are characteristic of cnidarians; (2) the existence of a definite mesoderm in the ctenophores; (3) fundamental differences in …
What characteristics to both corals and sea anemones have?
Corals, anemones and jellies are related and all classified in the phylum Cnidaria or “stinging needles.” The animals in this group are aquatic, possess stinging cells within their tissues and have a body plan characterized by radial symmetry, which allows all parts of their bodies to be equally receptive and …
What is the unique feature of phylum ctenophora?
Ctenophora Definition Ctenophores are free-swimming, transparent, jelly-like, soft-bodied, marine animals having biradial symmetry, comb-like ciliary plates for locomotion, the lasso cells but nematocytes are wanting.
Which are the distinguishing characters of phylum ctenophora?
General Characteristics of Phylum Ctenophora:
- Habitat: ADVERTISEMENTS:
- Habits: They feed on plankton, swim by cilia.
- Body Form: ADVERTISEMENTS:
- Symmetry: Symmetry is biradial (radial + bilateral).
- Germ Layers: They are diploblastic having ectoderm and endoderm.
- Level of Organisation:
- Appendages:
- Body Wall:
What are the similarities between Cnidaria and Ctenophora?
Similarities Between Cnidaria and Ctenophora Both Cnidaria and Ctenophora consist of coelenterate animals with a hollow gut. Both Cnidaria and Ctenophora contain a mouth, which is surrounded by tentacles. Both cnidarians and ctenophores are diploblastic animals. Both cnidarians and ctenophores contain mobile organisms.
How many species are there in the Cnidaria phyla?
It consists of two main phyla Cnidaria and Ctenophora and approximately 15000 species included. They are invertebrates and mostly marine organisms. There are freshwater species as well.
How are cnidarians different from other diploblastic animals?
The cnidarians are also called coelenterates since their body cavity is a hollow gut. They contain an incomplete digestive system and the mouth also serves as the anus. The cnidarians are diploblastic animals; hence, their body wall is made up of two cell layers: epidermis and the gastroderm.
How big is the body of a Ctenophora?
Ctenophora is a phylum of coelenterates, which consists of comb jellies. Ctenophores are exclusively marine animals that can be mostly identified in warmer seas. Typically, they float around the surface of the water. However, some ctenophores live in 3000 meters deep sea. Ctenophores have a pear-shaped body with a 5-20 mm diameter.