The ______controls the passage of food into the stomach.

Answer

**Step-by-Step Solution:**

1. **Understanding the Digestive Process**: The process of digestion begins in the mouth, where food is chewed and mixed with saliva to form a bolus.

2. **Formation of the Bolus**: The chewed food, combined with mucus from saliva, forms a soft mass called a bolus, which is essential for swallowing.

3. **Pathway of the Bolus**: After forming the bolus, it travels down the pharynx, which is a shared passageway for both food and air.

4. **Separation of Food and Air Pathways**: The pharynx leads to two different pathways: one to the esophagus (for food) and the other to the trachea (for air).

5. **Role of the Epiglottis**: To prevent food from entering the trachea (windpipe), there is a flap-like structure called the epiglottis. This structure closes off the trachea when swallowing, ensuring that food only enters the esophagus.

6. **Conclusion**: The epiglottis is crucial in controlling the passage of food into the stomach by directing it towards the esophagus and preventing it from entering the windpipe.

**Final Answer**: The **epiglottis** controls the passage of food into the stomach.

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