The blood consists of ameboid cells and haemoglobin dissolved in the plasma. Does th... Get solutions The ventral nerve cord has a swelling, or ganglion, in each segment, i.e. Just below the brain, the aortic arches look like a coil network wrapped around the esophagus or food pipe of the earthworm. 0 0 0. Ishan26. According to Doug Collicut, "In 1980, 370 million worms were exported from Canada, with a Canadian export value of $13 million and an American retail value of $54 million." An earthworm can be associated to have no heart or 10 pseudo hearts or aortic arches to be specific. In: Karaca A. It receives a pair commissural and dorsal intestines in each segment. Research from the Earthworms are sold all over the world; the market is sizable. Does the ventral nerve cord traverse the entire length of the body? Relevance. An unidentified Tasmanian earthworm shown growing a replacement head has been reported.Within the world of taxonomy, the stable 'Classical System' of Michaelsen (1900) and Stephenson (1930) was gradually eroded by the controversy over how to classify earthworms, such that Fender and McKey-Fender (1990) went so far as to say, "The family-level classification of the The families, with their known distributions or origins:From a total of around 7,000 species, only about 150 species are widely distributed around the world. d. How could absorption in the intestine … Biology Laboratory Manual (10th Edition) Edit edition. Aortic arches or Pseudo hearts are large muscular tubes and supply blood via alternate contraction and relaxation.The blood to different organ systems is carried via vessels. 4 years ago. The circulatory system comprising of three vessel system does the job for both Depending upon the species earthworms can grow up to Consider the hearts location it is located in the very upper region of the earthworm.If it had one aortic arch maybe it would have not survived as a species. These vessels are the aortic arches, dorsal blood vessels, and ventral blood vessels. If the rear of the worm is touched, a signal is rapidly sent forwards causing the longitudinal muscles in each segment to contract. These are the peregrine or cosmopolitan earthworms.Earthworms are classified into three main ecophysiological categories: (1) leaf litter- or compost-dwelling worms that are nonburrowing, live at the soil-litter interface and eat decomposing organic matter (Earthworm populations depend on both physical and chemical properties of the soil, such as temperature, moisture, pH, salts, This earthworm activity aerates and mixes the soil, and is conducive to mineralization of nutrients and their uptake by vegetation. An earthworm is a terrestrial invertebrate that belongs to the order Opisthopora.They exhibit a tube-within-a-tube body plan, are externally segmented with corresponding internal segmentation, and usually have setae on all segments. These nerves connect with the cricopharyngeal connective. Earthworms provide an excellent source of protein for fish, fowl and pigs but were also used traditionally for human consumption. On the surface, crawling speed varies both within and among individuals. Alternatively, if a “heart” is just an organ functionally similar to a human heart, then earthworms have up to 10 hearts (or 5 pairs of hearts). Segments 5-9 accommodate four pairs of spermathecal apertures. While, the other two pairs of lateral oesophageal hearts in 11 and 12 segments. At birth, earthworms emerge small but fully formed, lacking only their sex structures which develop in about 60 to 90 days.