I’ll tell about species also in aquasciences. First of all we’ll look over poriferans. Poriferans are commonly reffered to as sponges. They are animals of the phylum Porifera. They are primitive, sessile mostlymarine, water dwelling, filter feeders that pump water through their bodies to filter out particles of food matter.
Phylum Porifera is huge phylum that contains about 2500 species which lives in seas, lakes and rivers. Poriferans’ first examples ara belong to 600 million before present day. They’re the most primitive of multi pore animals and they have not improved tissue system. Sponges were being accepted as a plant untill 1830 by the researchers. At the end of the careful studies in following years, they were included in Kingdom Animalia. Poriferans have not an organ and a true tissue.
Choanocytes (also known as "collar cells") function as the sponge's digestive system and are remarkably similar to the protistan choanoflagellates.The collars are composed of microvilli and are used to filter particles out of the water. The beating of the choanocytes’ flagella creates the sponge’s water current.
Sponges have three body types: asconoid, syconoid and leuconoid;
Asconoid sponges are tubular with a central shaft called the spongocoel.The beating of choanocyte flagella forces water into the spongocoel through pores in the body wall. Choanocytes line the spongocoel and filter nutrients out of the water.
Syconoid sponges are similar to asconoids. They have a tubular body with a single osculum, but the body wall is thicker and more complex than that of asconoids and contains choanocyte-lined radial canals that empty into the spongocoel. Water enters through a large number of dermal ostia into incurrent canals and then filters through tiny openings called prosopyles into the radial canals. There food is ingested by the choanocytes. Syconoids do not usually form highly branched colonies as asconoids do. During their development, syconoid sponges pass through an asconoid stage.
Leuconoid sponges lack a spongocoel and instead have flagellated chambers, containing choanocytes, which are led to and out of via canals.
A sponge’s form can change as per conditions that it lives in. They accommodate to the ambient.
They can reproduce sexual and also asexual. They have not a special reproduction organ. Sexual reproduce is made by sex pores. Asexual reproduction is made by gemmation.
Sponges have no true circulatory system; however the water current is used for circulation. Dissolved gases are brought to cells and enter the cells via simple diffusion. Metabolic wastes are also transferred to the water through diffusion. Sponges pump remarkable amounts of water.
An example for Phylum Porifera:
Verongia aerophoba (Schmidt)
Famillia: Verongiidae
Eng: Tube sponge
Color: Their color is bright yellow.
Where they found: The reefs are their main living place. They can be seen near algae. Usually can be seen shallow waters. They’re appeared in Mediterranean and Agean Sea.
Characteristics: Their bodiesare as a column and their height is about 20 cm . The pores perform their staminal actions. Aerophoba means “don’t like air”. When they are injured or coming out of water, their colors turn into brown or black.
Nutrients: Their nutrients are plankton in the water, very small organisms and organic materials.
Pictures:
Resources: here, here and Derin Mavi Atlas (Deep Blue Atlas)
Pic1 (top-right): members.fotunecity.com
Pic2 (top-left): users.tamuk.edu
Pic3 (bottom-left): www.asturnatura.com
Pic4 (bottom-center): www.drm-drustvo.si
Pic5 (bottom-right): www.taucher.net
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