Question

which layer of the gl tract causes mixing contractions? a mucosa b submucosa c longitudinal muscles d circular muscles

Explanation:

The circular muscles of the gastrointestinal (GI) tract contract rhythmically to cause mixing contractions, known as segmentation contractions. These contractions help to mix food with digestive enzymes and move it back and forth in the lumen of the GI tract. The mucosa is the innermost layer involved in secretion and absorption, the submucosa contains blood vessels and nerves, and the longitudinal muscles are more involved in peristalsis (propulsive movements).

Answer:

D. Circular muscles