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.
Peristalsis in the Digestive System. Peristaltic waves are produced by contractions of smooth muscles. One set of smooth muscles contract behind the chewed food to keep it from moving back into the mouth. Another set of smooth muscles then pushes the food forward along the digestive tract.