owing: From the mouth, the food passes into the throat.

i. Identify the two important passage ways from the throat and explain
where each leads.
ii. Finally, the food must be propelled into the stomach. Explain what
peristalsis is and how it allows food to move into the stom

1 answer

i. From the throat (pharynx), there are two important passageways:

  1. Esophagus: This is a muscular tube that leads from the throat down to the stomach. The esophagus carries food from the pharynx to the stomach through a process of muscular contractions. After swallowing, food enters the esophagus and is directed to the stomach for further digestion.

  2. Trachea: This is the airway that leads to the lungs. It branches into the bronchi, which direct air into each lung. While food does not enter the trachea during swallowing, it is a critical passageway for air and opens up at the larynx (voice box) when breathing.

ii. Peristalsis is a series of wave-like muscle contractions that moves food through the digestive tract, including the esophagus. When food is swallowed, it creates a bolus (a rounded mass). The muscles of the esophagus and surrounding areas contract and relax in a coordinated manner to push the food downward into the stomach.

The process of peristalsis involves:

  • Contraction: The circular muscles behind the bolus contract to push it forward.
  • Relaxation: As the bolus moves downward, the muscles ahead of it relax, allowing space for the food to move into the stomach.

This action is rhythmic and continues along the entire length of the esophagus. Peristalsis is crucial in ensuring that food is effectively propelled down the digestive tract, enabling it to reach the stomach where further digestion occurs.