Results and Discussions
Autor: moto • January 28, 2013 • Essay • 661 Words (3 Pages) • 1,146 Views
Results and Discussion
Phylum Porifera has 8,000 describes species, 98% of which are marine and the remaining occur most abundantly in shallow freshwater. These animals are composed of loose masses of cells that are poorly organized into tissues which is evident in the non-distinction of their organ systems. Sponges are usually attached to a substrate by a pedal disk.
The body of a sponge consists of three layers: the pinacoderm, mesohyl layer and the choanocyte layer. The pinacoderm is perforated with numerous, minute incurrent ostia through which water enters. The water then goes straight to the body cavity, spongocoel after passing through a complex canal system. Poriferans exhibit three types of canal organization: the asconoid, syconoid and leuconoid. The simplest among the three is the asconoid which basically consists of incurrent pores, a spongocoel and an osculum. The second type of canal system, syconoid is more complex than the asconoid. It exhibits in-folding and out-folding of the body wall, reducing the spongocoel. This type of organization increases the surface area of the choanocyte layer making the movement of water inside the sponge more proficient. Leuconoid, the third type is the most efficient canal system. In this type of canal organization, the spongocoel virtually disappears and the body walls folds inward and outward further to form numerous flagellated chambers. The mesohyl layer is a supporting layer made up of a gelatinous matrix containing collagen.
Results and Discussion
Phylum Porifera has 8,000 describes species, 98% of which are marine and the remaining occur most abundantly in shallow freshwater. These animals are composed of loose masses of cells that are poorly organized into tissues which is evident in the non-distinction of their organ systems. Sponges are usually attached to a substrate by a pedal disk.
The body of a sponge consists of three layers: the pinacoderm, mesohyl layer and the choanocyte layer. The pinacoderm is perforated with numerous, minute incurrent ostia through which water enters. The water then goes straight to the body cavity, spongocoel
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