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Rhetorical Analysis Of Earthworms

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Introduction The Common Earthworm, Lumbricus terrestris, is a terrestrial invertebrate found abundantly across the United States. Physically, it has a red-brown color, can measure in length up to fourteen inches, and can weigh up to .39oz. The body of the earthworm is made up of ring-like segments, annuli, and covered in small bristles, setae, that help the worm to move and burrow (National Geographic, 2017). The earthworm uses peristaltic waves as its form of locomotion (Kuroda et al, 2014). Within the segments, the earthworm has two types of muscles, circular and longitudinal. The contraction of the circular muscles causes the segment to become shorter, while the contraction of the longitudinal muscles causes the segment to lengthen. The resulting pattern in all segments of the earthworm’s body causes it to move forward in a wave-like pattern, with one segment moving after another (Piearce, 1983). There are kinetics involved in the locomotion of earthworms that are directly related to its morphology. Research conducted by scientists from the zoological department at Cambridge University on the locomotory reflexes in the earthworm found that the tactile sense organs on the ventral surface of the earthworm affect the longitudinal contractions. Therefore, when an earthworm moves over an irregular surface, its tension reflexes are altered depending on the certain environment (Gray & Lissmann, 1938). Our research question is: How does the locomotion of an earthworm vary

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