 Classification: Kingdom: Animalia Phylum: Ctenophora ( comb-jellie) Ctenophora principals characteristics: * Characterized for 8 rows of combs; * Formed by plates of closely-spaced cilia that are fused at the bases and used for locomotion; * Each single comb within a row is made up of several thousand cilia; * The Ctenophora habitat is only marine and localized worldwide; * Composed of about 150 species, which most of these are poorly known; * Most have Colloblasts - secrete a sticky substance for catching animals to prey capture; * Symmetry is biradial (but in some animals the internal canals characteristics and position of the tentacles can change in a combination of radial and bilateral); * Diploblastic; (but in some adults body at the middle layer contain cells and the derivation of these middle layer of cell are controversies if is ectodermal or endodermal - affecting if is diploblastic or triploblastic); * Complete gut; wastes exit via anal pore and mouth; * They are carnivorous, and prey on a variety of planktonic animals; Diversity: The Ctenophora's phylum are composed of about 150 species. were "previous" divided in two classes, Tentaculata and Nuda. the ctenophora diversity is still uncertain can't be divided in subgroups. Coast species - 3 most common Orders:
  http://jellieszone.com/pleurobrachia.htm
  http://tolweb.org/tree?group=Ctenophora&contgroup=Animals
  http://jellieszone.com/beroe.htm * Deiopea kaloktenota > can found near to the surface of the oceans - extremely transparent *Oceanic ctenophores tend to be much more fragile that coastal species, because they do not need to tolerate wave action or the turbulence and sediment load of coastal waters.  http://www.lifesci.ucsb.edu/~biolum/organism/pictures/deiopea.html * "still-undescribed" > highly pigmented ( 1000 meters)  http://www.lifesci.ucsb.edu/~biolum/organism/pictures/tortugas.html Curiosity: Ctenophora luminesce or bioluminescence:
Ctenophora cycle life: * Is a sample life cycle. Most of the Ctenophores species are hermaphroditic ( a singles ctenophore produce eggs and sperms). Eggs and sperm are typically released directly into the water through the mouth and the eggs are fertilized externally and develop. Self fertilization is possible, but it's not clear how often that happens. Physiology: > representative type: Pleurobrachia
Respiration and Excretion: * occur through the body surface; * no respiratory system; * no coelomic cavity; Nervous and Sensory Systems: * consisting of a subepidermal plexus concentrated around the mouth, this structure holds a statolith that sits on 4 clumps of large sensory cilia (the balancers) and determines orientation of the comb jelly; and beneath the comb plate rows, that can maintain proper vertical orientation or change swimming direction. Ecology: * Ctenophores make up a significant component of the plankton. Famously, the ctenophore Mnemiopsis, which was introduced into the Black sea prior to the 1980s, proved to be a major pest. The species feeds on zooplankton, including juvenile fish and their eggs, resulting in dramatic declines of fish populations in the region and in a big ecological damage. * The fact of the Ctenophores, specially the type of is common member of planktons, which had small size (a few mm) and transparency make relatively inconspicuous, so even though they are not uncommon, in
general they are little known; Curiosities:
Video: Pictures: http://www.astrobio.net/albums/origins/aif.jpg  http://jellieszone.com/images/beroe2.jpg   www.microscopy-uk.org.uk/ mag/imgmay98/comb2n.jpg www.at-sea.org  1.bp.blogspot.com/.../ Comb+Jellies-718238.jpg   www.asknature.org/images/ uploads/strategy/6a3  www.discoverlife.org/.../ Ctenophore Work Citation:
AES 112 - Animal Biology | ||||
