Which are the primary functions of the digestive system?

Which are the primary functions of the digestive system?

• A. Ingestion, secretion, motility, digestion, absorption, elimination
• B. Ingestion, filtration, respiration, absorption
• C. Digestion, excretion, hearing, vision
• D. Ingestion, digestion, respiration, circulation

Answer: (A)

The digestive system’s job is to convert food into nutrients the body can use and to remove what isn’t absorbed. The main functions line up in six connected steps: ingestion (taking food into the mouth), secretion (releasing fluids like saliva, stomach acid, bile to help digestion), motility (moving the contents along the GI tract through movements such as peristalsis), digestion (breaking down food mechanically and chemically), absorption (taking nutrients into the bloodstream), and elimination (getting rid of indigestible waste as feces). Together, these processes handle everything from initial intake to final disposal, supported by the stomach, intestines, and accessory organs like the liver and pancreas. The other options mix in functions from other systems (filtration by the kidneys, respiration by the lungs, hearing and vision by sensory organs, circulation by the heart and vessels), which aren’t primary roles of the digestive tract. While waste management is a common theme, the strongest match for the digestive system’s scope is the sequence that covers bringing in food, processing it, taking up nutrients, and expelling leftovers.

The digestive system’s job is to convert food into nutrients the body can use and to remove what isn’t absorbed. The main functions line up in six connected steps: ingestion (taking food into the mouth), secretion (releasing fluids like saliva, stomach acid, bile to help digestion), motility (moving the contents along the GI tract through movements such as peristalsis), digestion (breaking down food mechanically and chemically), absorption (taking nutrients into the bloodstream), and elimination (getting rid of indigestible waste as feces). Together, these processes handle everything from initial intake to final disposal, supported by the stomach, intestines, and accessory organs like the liver and pancreas.

The other options mix in functions from other systems (filtration by the kidneys, respiration by the lungs, hearing and vision by sensory organs, circulation by the heart and vessels), which aren’t primary roles of the digestive tract. While waste management is a common theme, the strongest match for the digestive system’s scope is the sequence that covers bringing in food, processing it, taking up nutrients, and expelling leftovers.