Deena has been working as biology content writer and an ex researcher in biotechnology
The phylum Ctenophora takes its name from two Greek words, ktenos= comb and phora= bearing, as they possess eight comb like plates of locomotion. Ctenophora is a small phylum of marine animals, which are commonly known as comb jellies (sea walnuts) due to their jelly like consistncy and comb like locomotory organs. At night they are often bioluminescent. About 60 species of ctenophoran animals are known. The ctenophoran animals are closely allied to coelenterates.
Body is usually pear shaped (Example: Pleurobrachia) or ribbon like flat(Cestus).
General Characters of Phylum Ctenophora
- Marine, solitary, free swimming or pelagic.
- No polymorphism and no attached stages.
- Body transparent.
- Cell tissue grade of body organization.
Ctenophora Digestive System
Digestive system with mouth, stomach, complex gastrovascular canals and two aboral anal pores
- Symmetry biradial along an oral aboral axis.
- Body acoelomate and triploblastic, with an outer epidermis, inner gastrodermis and middle jelly like mesogloea with scattered cells and muscle fibres.
- External surface with eight vertical rows of comb plates of fused cilia of locomotion. Hence they are named comb jellies.
- A pair of long, solid, rectractile tentacles present.
Unique Features of Ctenophora
- Comb like ciliary plates for swimming.
- Special adhesive cells, the colloblasts for capturing the prey
- Two anal pores.
- Mesogloea with amoebocytes and smooth muscle cells
- Nematocysts absent. Instead, special adhesive and sensory cells, called colloblasts, present on tentacles, help in food capture. Skeletal,circulatory , respiratory and excretory organs absent.
- nervous system diffuse. Aboral ends bears a sensory organ, the statocyst.
- All monoecious(hermaphrodite). Gonads develop side by side on digestive canals and develop from endoderm.
- Development of ctenophores usually includes a characteristic cydippid larva.
- Alternation of generation and asexual reproduction absent.
- Regeneration and Paedogenesis common.
Classification of Phylum Ctenophora
- Class Tentaculata and Class Nuda
Phylum Ctenophora grouped into two classes: Class Tentaculata and Class Nuda
Sea Gooseberry (Pleurobrachia bachia) Feeding - Comb Jellyfish, Phylum Ctenophora
More about Animal Kingdoms
- Animal Kingdom Classification
Classification of Animal Kingdom: Non Chordata and Chordata
- Example of Chordata
Phylum Chordata with examples
- Example of Non Chordata
Non Chordata : Characteristics with Examples
- Phylum Porifera: General Characters and more
The Phylum Porifera include more than 5000 animal species, mostly marine, but includes about 150 fresh water inhabitants also. They found in all seas, wherever there are rocks, shells, submerged timbers, or coral to provide a suitable substratum.
- Phylum Cnidaria (Coelenterata): General Characters and more
Phylum Cnidaria (formely known as coelenterata) includes about 9000 species.Some are found in fresh water, but the grater number are marine. Coelenterates (Gr. koilos, hollow+enteron,gut).are the simplest of eumetazoans.
- Coral and Coral Reefs
Corals are animals belonging to the phylum Coelenterata. The corals in general have diverse shapes and sizes, but majority are colonial with very small polyps. A coral reef is a complex living community
- Phylum Platyhelminthes : General Characters
General Characters of Phylum Platyhelminthes
Ebong Napoleon. M. on December 04, 2019:
Fahad Afaque on October 18, 2018:
Aakash ingawale on August 07, 2018:
It is Very useful information
kanagavel on August 15, 2017:
Balveen Gaubrey on November 16, 2016:
Priya singj on November 09, 2016:
Good and helpful
nubdha ismayil on September 19, 2016:
Shivender kumar on July 06, 2016:
niharika on November 12, 2015:
maheen on October 09, 2015:
sumera khan on April 15, 2015:
M Irfan Riaz on January 15, 2015:
Very very god
gokul on October 04, 2014:
Arjun on September 14, 2014:
Arjun on August 05, 2014:
perveen on May 23, 2014: