MATTHEW CASTELLANOSKRISTOPHER JAMES

GEOFFREY SCOTT

Comb Jellies

Radial Symmetry Revisited

-Phylum:Ctenophora-Exclusive marine

group of about 100 species

- Comb jellies are radially symmetrical and similar in appearance to cnidarians but possess eight rows of ciliary combs

Characteristics of Ctenophora

1)Radially or biradial Symmetrical. 2)Body multicellular, few tissues, some organs and organelles. 3)Body contains an internal cavity and a mouth and anal pores. 4)Swims by means of plates of cilia (the combs)

Characteristics continued

5)Reproduction mostly sexual as hermaphrodites, occasionally asexual. 6)Has a well developed subepidermal nerve net. 7)Has a distinct larval stage which is planktonic. 8)Lives in marine environments. 9)All are carnivorous.

COMB JELLIES continued

The phylum Ctenophora is a small phylum containing about 90 species of generally small and delicate animals known as Comb Jellies. Many species are quite and many are also almost transparent, a few species can be very beautiful as they have the ability to produce green and blue coloured light. There are between 100 and 150 species of Ctenophora known to science.

COMB JELLIES continued(again)

All ctenophores are hermaphroditic (meaning they possess both male and female reproductive organs), a very few species can reproduce asexually. Eggs and sperm are shed into the water and after fertilisation an ovoid larvae develops called a Cydippid larvae. This free swimming larvae grows naturally into a new Comb Jelly in most species. In the laterally flattened species such as Cestum there is a sort of metamorphosis.