Which system is primarily involved in the absorption of nutrients from food?

The digestive system is primarily responsible for the absorption of nutrients from food. This system includes various organs such as the mouth, esophagus, stomach, small intestine, and large intestine.

During the digestive process, food is broken down into smaller components through mechanical and chemical means. The small intestine is particularly crucial, as its extensive surface area, enhanced by villi and microvilli, allows for maximum nutrient absorption into the bloodstream. Nutrients such as carbohydrates, proteins, fats, vitamins, and minerals are absorbed here and then transported throughout the body to provide energy and support cellular functions.

In contrast, the other systems mentioned have different roles. The endocrine system regulates bodily functions through hormones, the nervous system handles signaling and responses, and the circulatory system transports blood, which can include nutrients but isn't primarily responsible for their absorption. Each of these has essential functions but does not directly engage in the absorption processes as the digestive system does.