ACE Personal Trainer Practice Exam 2026 - Free Personal Trainer Practice Questions and Study Guide

The correct answer is that the removal of carbon dioxide from blood is not a function of the digestive system. The primary role of the digestive system is to break down food into smaller components that can be absorbed into the body for energy and nutrition.

Ingestion and movement of food involves the intake of food through the mouth and the process of moving it through the digestive tract. Mechanical preparation and chemical digestion are critical processes that occur mainly in the mouth, stomach, and small intestine, where food is physically broken down and chemically transformed. Absorption of digested food takes place predominantly in the small intestine, where nutrients move into the bloodstream and are transported to various parts of the body for use.

In contrast, the removal of carbon dioxide from blood is primarily a function of the respiratory system, which involves processes such as breathing and gas exchange within the lungs. Therefore, this option does not pertain to the digestive system's functions, which focus solely on processing food and extracting nutrients.