Anatomy and Physiology II Practice Test

Which of the following is not an organ of the digestive system?

1. Stomach

2. Spleen

3. Pancreas

4. Colon

The correct answer is: Spleen

The spleen is not considered an organ of the digestive system. Instead, it is part of the lymphatic system and primarily functions in filtering blood, recycling iron, and helping in the immune response by producing white blood cells. In contrast, the stomach, pancreas, and colon are all integral components of the digestive system. The stomach plays a crucial role in breaking down food using gastric juices. The pancreas aids digestion by producing enzymes that help break down carbohydrates, fats, and proteins, and it also regulates blood sugar levels through hormone production. The colon, or large intestine, is involved in the absorption of water and electrolytes and the formation and storage of feces. Each of these organs directly participates in the digestion and absorption of nutrients, establishing their essential roles in the digestive system while highlighting the spleen's distinct function outside of this system.