Search results
Results From The WOW.Com Content Network
As soft-bodied invertebrates, they lack a true skeleton, but their structure is maintained by fluid-filled coelom chambers that function as a hydrostatic skeleton. [citation needed] Earthworms have a central nervous system consisting of two ganglia above the mouth, one on either side, connected to an axial nerve running along its length to ...
Earthworms store their partners' sperm in spermathecae ("sperm stores") and then the clitellum produces a cocoon that collects ova from the ovaries and then sperm from the spermathecae. Fertilization and development of earthworm eggs takes place in the cocoon. Leeches' eggs are fertilized in the ovaries, and then transferred to the cocoon.
However, 'earthworm' can be a source of confusion since, in most of the world, other species are more typical. For example, through much of the unirrigated temperate areas of the world, the "common earthworm" is actually Aporrectodea (=Allolobophora) trapezoides, which in those areas is a similar size and dark colour to L. terrestris.
lack a vascular blood system diffusion and osmosis circulate nutrients and waste products throughout the body. lack a skeleton hydrostatic pressure gives the body a supportive framework that acts as a skeleton. no segmentation; body wall epidermis and muscle; often syncytial; usually covered by a secreted cuticle; most are microscopic
Oligochaetes are well-segmented worms and most have a spacious body cavity (coelom) used as a hydroskeleton.They range in length from less than 0.5 mm (0.02 in) up to 2 to 3 metres (6.6 to 9.8 ft) in the 'giant' species such as the giant Gippsland earthworm (Megascolides australis) and the Mekong worm (Amynthas mekongianus).
A non-helical hydrostatic skeleton structure is the functional basis of the mammalian penis, [3] which fills the corpus cavernosa with blood to maintain physical rigidity during coitus. Helically reinforced hydrostatic skeleton structure is typical for flexible structures as in soft-bodied animals.
Being a morphological grouping rather than a true phylogenetic group, soft-bodied organisms vary enormously in anatomy. Cnidarians and flatworms have a single opening to the gut and a diffuse nerve system. The roundworms, annelids, molluscs, the various lophoporate phyla and non-vertebrate chordates have a tubular gut open at both ends.
Megascolecidae is a family of earthworms native to Madagascar, Australia, New Zealand, Asia, and North America. [2] At up to 2 meters in length, [3] their large size distinguishes the Megascolecidae from other earthworm families.