In biochemistry, a consecutive series of chemical reactions (where the product of one reaction is the reactant of the next reaction) form metabolic pathways. These reactions are often catalyzed by protein enzymes.hemical reactions happen at a characteristic reaction rate at a given temperature and chemical concentration.
The digestive system of an ascarid consists of four parts: Alimentary Canal, Mouth, Pharynx, and Intestine. The alimentary canal compromises a short pharynx or esophagus representing the foregut, a long intestine or mod-gut, and a short rectum or hind gut.he stomodeum consists of the âmouth and lipsâ, buccal cavity, and the pharynx (esophagus). Each of these regions are used extensively in taxonomy as well as classification of nematodes, and for providing as indication of feeding habit or trophic group.
The muscularis mucosa allows for movement of the mucosa independent of the wall of the digestive tract, thereby increasing its contact with food. In most of the alimentary canal, the muscularis mucosa consists of an inner circular and outer longitudinal layer of smooth muscle.The Submucosa: The submucosa consists of moderately dense irregular connective tissue. It contains blood and lymph vessels and nerve plexi.n most of the digestive tract, the muscularis externa consists of an inner circular and outer longitudinal layer of smooth muscle. The inner circular layer is arranged in a tight spiral, and its contraction results in the mixing of food by constricting the lumen of the tube.