Which system helps in food degradation and absorption of nutrients?

The digestive system is essential because it is specifically responsible for the process of breaking down food into smaller, absorbable components. This system consists of various organs, including the mouth, esophagus, stomach, intestines, liver, pancreas, and gallbladder, each playing a vital role in digestion and nutrient absorption.

In the mouth, food is mechanically broken down by chewing and mixed with saliva, which contains enzymes that begin the digestion of carbohydrates. As food travels through the esophagus to the stomach, it is further mixed with gastric juices that help digest proteins. In the small intestine, the majority of nutrient absorption occurs, as the walls of this organ are lined with villi and microvilli that increase the surface area for absorption. The digestive system also incorporates accessory organs, like the liver and pancreas, which produce bile and digestive enzymes that aid in breaking down fats, carbohydrates, and proteins.

Understanding the functions of the digestive system clarifies why it is the correct answer in this context, as no other system listed is primarily involved in the degradation of food or the absorption of nutrients. The cardiovascular system facilitates the distribution of nutrients but does not engage in the digestive process itself, while the respiratory system is involved in gas exchange, not nutrient absorption.