1 In-text citations in parenthesis, with only the author's last name and page number included (Smith, p. 4). 2  Double-spaced lines, but with no extra line breaks between each citation. 3  Footnotes (superscripted) also used to provide non-essential information.
Muscularis: The muscularis is responsible for segmental contractions and peristaltic movement in the GI tract. The muscularis is composed of two layers of muscle: an inner circular and outer longitudinal layer of smooth muscle.
The GI tract contains four layers: the innermost layer is the mucosa, underneath this is the submucosa, followed by the muscularis propria and finally, the outermost layer-the adventitia. The structure of these layers varies, in different regions of the digestive system, depending on their function.