Question

How is the stomach involved in the circulatory and nervous systems?

Answer 1

Hint: Stomach is an organ involved in digestion and forms a part of the alimentary system. Circulatory system includes the blood vascular system and lymphatic system, which transports various substances from one part of the body to another. Nervous system controls and coordinates different activities of various body parts.

Complete answer:
Different organ systems in the body interact with each other and depend on one another to function. Stomach is the widest organ of the alimentary canal. It stores food for some time, ultimately breaking up the food and mixing the pieces with gastric juice. Alcohol, aspirin, some lipid-soluble drugs, moderate amounts of sugar and water are absorbed by the stomach wall. These absorbed substances are passed from the stomach wall into the circulatory system i.e., blood and lymph through its mucous membrane. The absorbed food material is transported by blood to different parts of the body cells where these nutrients are used for energy, growth and repair. Stomach is dependent on blood to transport the absorbed nutrient, thus interconnecting the two.

Nervous system controls and coordinates the activities of various organs. The activities of the alimentary canal come under two types of nervous controls: intrinsic nervous system (enteric nervous system) and extrinsic nervous system (parasympathetic and sympathetic nerves). The enteric nervous system controls functions like secretion and motility. It is also known as the second brain of the stomach. The extrinsic nervous system can modify activities of the intrinsic system in response to reflex activity initiated by gastro-intestinal tract.

Note: Proteins and fats are partially digested by stomach which are passed on to the small intestine for further digestion. The sight, smell and presence of food in the gastro-intestinal tract act as the stimuli for the secretion of saliva. This happens by the simulation of the vagus nerve.