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Planarian Sensory Organs

Submitted by alexispena on Fri, 11/10/2017 - 10:36

Planarians have a nervous system composed of two main nerve chords running from their head to their tail, and connected by transverse nerves. Although basic, planarians have been shown to exhibit decision making behavior by processing external stimuli.  Planarians are able to process external stimuli by their sensory organs, eye spots and auricles. The eyespots are located on the head of the planarians and are used to detect light. The behavior in response to the change in light is called phototaxis. Planarians exhibit negative phototaxis, moving away from the light source. Auricles are on the side of the planarians head, and contribute to its triangular shape. The auricles contain chemoreceptors which respond to chemical stimuli. The auricles can play a role in finding food or the detection of changes in habitat. Both their photoreceptors and auricles help them make decisions about their environment. 



Well done in writing your paragraph, the only suggestion would be one change "Planarians are able to process" to Planarians can process.

This is a very well formatted paragraph that is easy to follow. One adjustment you could make is you say "planarians are able to process external stimuli by their sensory organs, eyespots and auricles," however you only go into more depth on the eyespots and auricles. As a reader if you go into depth on 2 of the topics I expect you to go into depth on the third.