Phylum Platyhelminthes
Representative Animals: Flat worms, and Tapeworms
Habitat: Platyhelminthes usually live under water in sandy areas, but some can live on a host (e.g. the well known tapeworm) and others can live in soil. It depends on the class, family, genus and so forth.
Reproductive System: Platyhelminthes are able to reproduce both asexually and sexually. They reproduce asexually by means of regeneration. Most Platyhelminthes are hermaphroditic so that when they come across another flatworm they are able to copulate. This is an adaptation often found in animals who spend most of their lives alone. Flat worms have a particularly peculiar mating ritual called penis fencing. The loser of this match must become the responsible female and the winner will be the male.
Reproductive System: Platyhelminthes are able to reproduce both asexually and sexually. They reproduce asexually by means of regeneration. Most Platyhelminthes are hermaphroditic so that when they come across another flatworm they are able to copulate. This is an adaptation often found in animals who spend most of their lives alone. Flat worms have a particularly peculiar mating ritual called penis fencing. The loser of this match must become the responsible female and the winner will be the male.
Respiratory System: Platyhelminthes do not have a respiratory system but preform gas exchange by diffusion.
Digestive System: The Platyhelminthes also have a GVC. These animals also contain a mouth, pharynx and intestines that branch off from one another. Undigested food is then expelled out of the mouth and nitrogenous nutrients are diffused through the ectoderm.
Circulatory System: Platyhelminthes do not have a circulatory system but it is replaced by diffusion across different germ layers, including that of the GVC. Platyhelminthes also depend on the cilia that line the GVC to move fluid and nutrients throughout the body.
Type of Symmetry: Platyhelminthes are the first phylum to have strictly bilateral symmetry.
Type of Coelom: No coelom (acoelomate) .
Type of Body Plan: Platyhelminthes have true organs and are unsegmented.
Number of body layers: Three body layer - ectoderm, mesoderm and endoderm
Digestive System: The Platyhelminthes also have a GVC. These animals also contain a mouth, pharynx and intestines that branch off from one another. Undigested food is then expelled out of the mouth and nitrogenous nutrients are diffused through the ectoderm.
Circulatory System: Platyhelminthes do not have a circulatory system but it is replaced by diffusion across different germ layers, including that of the GVC. Platyhelminthes also depend on the cilia that line the GVC to move fluid and nutrients throughout the body.
Type of Symmetry: Platyhelminthes are the first phylum to have strictly bilateral symmetry.
Type of Coelom: No coelom (acoelomate) .
Type of Body Plan: Platyhelminthes have true organs and are unsegmented.
Number of body layers: Three body layer - ectoderm, mesoderm and endoderm
Specialized Cells: Platyhelminthes have a unique specialized cell called 'The Flame Cell'. 'The Flame Cell' is a specialized cell that functions similar to a kidney and remove unneeded toxins from the flatworm.