Which of the following bodily systems is primarily involved in the absorption of nutrients?

The digestive system is primarily responsible for the absorption of nutrients. This system consists of various organs including the mouth, esophagus, stomach, small intestine, and large intestine, each playing a critical role in the process of digestion and nutrient absorption.

During digestion, food is broken down into its constituent nutrients—vitamins, minerals, carbohydrates, proteins, and fats. The small intestine, in particular, is where the majority of absorption occurs. Its large surface area, facilitated by villi and microvilli, allows for maximized nutrient uptake into the bloodstream. Once absorbed, these nutrients are then transported to the rest of the body via the circulatory system for use in energy production, growth, and cellular repair.

In contrast, while the respiratory system is essential for gas exchange (oxygen and carbon dioxide), it does not play a direct role in nutrient absorption. The circulatory system does transport absorbed nutrients but is not responsible for their absorption itself. The nervous system is chiefly involved in controlling bodily functions and processes but does not have a role in nutrient absorption. Thus, the digestive system is the correct answer, as it is specialized for the entire process of breaking down food and absorbing essential nutrients.