The most common form of movement in the digestive tract is

The most common forms of movement in the digestive tract are as follows:

1. Peristalsis: forward propulsive movement, which is the most common form of movement in the digestive tract.

2. Segmented movement: Alternate contraction and relaxation of a certain segment of the digestive tract, which is a unique form of movement of the small intestine.

3. Receptive relaxation: Reflexive relaxation when the digestive tract accepts food, which is a unique form of movement of the stomach.

4. Tonic contraction: The slow, weak and continuous contraction of the smooth muscle of the digestive tract is the basic movement of the digestive tract.

Structure of the digestive system:

The entire digestion process of the digestive system includes three methods: mechanical digestion, chemical digestion and biological digestion. Mechanical digestion is the process of grinding, mixing and transporting food through the peristalsis of the digestive tract. Chemical digestion refers to the process in which various digestive enzymes in the digestive juice decompose substances with complex molecular structures in food into substances with relatively simple structures.

Biological digestion refers to the digestive process involving microorganisms in the intestine. These three digestion methods coordinate with each other, from front to back, and are fully mixed with the digestive juice to achieve complete digestion and absorption. After the residue is excreted from the body, the digestive process operates in a coordinated manner and is controlled by the nerves.

In the brain, there is a feeding center, a satiety center and a drinking center. The interaction between them determines the animal's appetite, drinking water and a series of other digestive processes.