ISSA Nutritionist Practice Exam

The primary function of the large intestine is to?

1. Digest food

2. Absorb water and electrolytes

3. Produce bile

4. Filter blood

The correct answer is: Absorb water and electrolytes

The primary function of the large intestine is to absorb water and electrolytes from the indigestible food matter that passes through it. As food is processed in the digestive tract, it becomes fluid and is somewhat fermented by bacteria in the large intestine. The large intestine reabsorbs a significant amount of water and essential minerals back into the body, leading to the formation of solid waste (feces). This absorption process is crucial for maintaining fluid and electrolyte balance in the body, which is vital for overall health. The other options refer to functions that do not primarily occur in the large intestine. The digestion of food mainly takes place in the stomach and small intestine. Bile is produced in the liver and stored in the gallbladder, not generated by the large intestine. Filtering blood is a primary function of the kidneys, not the large intestine. Therefore, the focus on water and electrolyte absorption accurately captures the main role of the large intestine in the digestive system.