Phylum Annelida
Representative Animals: leeches, earthworms
Habitat: Mostly found in soil. Leeches are often found in fresh water, though certain species can be found in salt water or even in damp soil.
Reproductive System: Annelida reproduce sexually. They are hermaphroditic, meaning they have both male and female reproductive organs. Their clitelum creates mucus that is used both to help with copulation and to create a cocoon for egg incubation.
Respiratory System: Annelida do not have a respiratory system but rather perform gas exchange using diffusion.
Digestive System: Phylum annelida have a complete digestive system, meaning it has two separate holes for the mouth and anus. Annelida have the following digestive organs: Pharynx, esophagus, calciferous glands, crop, gizzard, and intestine.
Circulatory System: The annelida has a closed circulatory system - it is the first phylum to have this. It uses its 5 aortic arches to pump blood through the dorsal blood vessel the blood then returns to the heart via the ventral blood vessel.
Reproductive System: Annelida reproduce sexually. They are hermaphroditic, meaning they have both male and female reproductive organs. Their clitelum creates mucus that is used both to help with copulation and to create a cocoon for egg incubation.
Respiratory System: Annelida do not have a respiratory system but rather perform gas exchange using diffusion.
Digestive System: Phylum annelida have a complete digestive system, meaning it has two separate holes for the mouth and anus. Annelida have the following digestive organs: Pharynx, esophagus, calciferous glands, crop, gizzard, and intestine.
Circulatory System: The annelida has a closed circulatory system - it is the first phylum to have this. It uses its 5 aortic arches to pump blood through the dorsal blood vessel the blood then returns to the heart via the ventral blood vessel.
Type of Symmetry: Annelids, like Platyhelminthes, have bilateral symmetry.
Type of Coelom: Annelids are Coelomates meaning they have a fluid filled cavity between the endoderm and mesoderm. Having a coelom is an advantage to the circulatory system because it makes it easier for nutrients to move throughout the body.
Type of Body Plan: segmented and metamerism. Metamery is a term used to decribe when the the body segment are placed in groupings to help the animal better perform life functions.
Number of body layers: Species within phylum annelida have 3 body layers: ectoderm, mesoderm and endoderm.
Specialized Cells: Earthworms have specialized cells that create setae on the ventral side of the earthworm. Setae are found on the ventral side of annelids (not leaches) and help with movement by providing grip.
Type of Coelom: Annelids are Coelomates meaning they have a fluid filled cavity between the endoderm and mesoderm. Having a coelom is an advantage to the circulatory system because it makes it easier for nutrients to move throughout the body.
Type of Body Plan: segmented and metamerism. Metamery is a term used to decribe when the the body segment are placed in groupings to help the animal better perform life functions.
Number of body layers: Species within phylum annelida have 3 body layers: ectoderm, mesoderm and endoderm.
Specialized Cells: Earthworms have specialized cells that create setae on the ventral side of the earthworm. Setae are found on the ventral side of annelids (not leaches) and help with movement by providing grip.