What happens in the digestive system when eating a cheese sandwich?

As you bite into the sandwich, your teeth break down the bread and cheese into smaller pieces. The proteins in the sandwich begin to break down into amino acids, while the carbohydrates break down into simple sugars.

2. The esophagus:

The esophagus carries the chewed food from the mouth to the stomach through peristaltic contractions. These are rhythmic muscle contractions that push the food down the esophagus.

3. The stomach:

The stomach is a J-shaped organ that churn the food mechanically and secretes acids such as hydrochloric acid, and enzymes like pepsin, which start the digestion process of carbohydrates, fats and proteins, to form a semi-liquid substance called chyme.

4. The small intestine:

The small intestine is the longest part of the digestive system. Here, the chyme is mixed with various digestive juices from the pancreas, liver and the intestinal walls, including bile, pancreatic juice, and intestinal juices, which further breaks down the carbohydrates, proteins, and fats into simpler molecules. The bile helps in the digestion of fats while enzymes such as amylase, protease, and lipase completes the digestion of carbs, proteins and fats respectively.

5. The large intestine:

The undigested material (called stool) is passed to the large intestine, where water is absorbed and electrolytes are balanced. Here beneficial bacteria break down the remaining food to release energy and produce vitamins such as Vitamin K and certain B vitamins.

6. The rectum:

The rectum is the final part of the digestive system and when stool builds up here, it triggers the sensation to defecate. The waste products that are not needed by the body are expelled as stool through the anus during bowel movements.