Final answer:
The digestive system is made up of the gastrointestinal tract and accessory organs. The gastrointestinal tract includes the mouth, esophagus, stomach, small intestine, and large intestine. Accessory organs like the liver, pancreas, and gallbladder play a critical role in digestion by producing enzymes and other substances.
Step-by-step explanation:
The digestive system is a complex network of organs responsible for breaking down food, absorbing nutrients, and expelling waste. The gastrointestinal tract (GI tract) is a continuous tube that starts at the mouth and ends at the anus, which includes the esophagus, stomach, small intestine, and large intestine. Accessory organs, such as the liver, pancreas, and gallbladder, produce vital substances for digestion like enzymes. While food doesn't pass through these accessory organs, they play a crucial role in breaking down food so that nutrients can be absorbed by the body.
On a diagram of the digestive system (such as Figure 18.2.2), Isaac would label the following primary organs:
- The mouth initiates digestion by mechanical and chemical processes.
- The esophagus is a muscular tube that transports food to the stomach.
- The stomach further breaks down food with acid and digestive enzymes.
- The small intestine, including the ileum, absorbs nutrients into the bloodstream.
- The large intestine absorbs water and forms feces from undigested material.
- Accessory organs like the liver, pancreas, and gallbladder which provide digestive enzymes and other substances necessary for digestion.
Understanding the functions and locations of these organs is critical for grasping how the digestive system works as a whole.