Video Transcript
Which of these is a common passage
for both food and air? (A) Nose, (B) pharynx, (C) larynx,
or (D) esophagus.
The question asks us about a
structure that’s involved in the passage of food and air. Take a moment to see if you can
remember which organ system is involved in the consumption of food. What about the inhalation of
air? The systems responsible for these
actions are the digestive system and the respiratory system. To answer the question correctly,
we first need to review some basic anatomy of the digestive and respiratory
systems.
You might remember that the
digestive system begins with the consumption of food through the mouth. Here, mechanical digestion begins
with the chewing of food, and chemical digestion begins when carbohydrates are
broken down by the enzyme amylase. In the mouth, food is mixed with
saliva to form a bolus. This bolus is swallowed and then
moved to the pharynx. Next, the bolus travels to the
esophagus, which is a long tube connecting the pharynx to the stomach. Once the bolus arrives at the
stomach, further digestion occurs, thanks to secretions from accessory organs, such
as the liver and pancreas.
The respiratory system involves
inhalation of air in order to obtain oxygen, which is required by all cells in the
body. Air can be inhaled through the nose
or mouth. In either case, it moves from the
site of inhalation into the pharynx. The pharynx connects with two major
structures: the esophagus, as we saw earlier, and the larynx, a structure
responsible for speech. The esophagus and larynx are
separated by a small flap of tissue called the epiglottis. It is responsible for directing
food and air to the correct organ systems. Food moves to the esophagus, while
air moves to the larynx.
We now have enough information to
answer our question. Both food and air will travel via
the mouth and pharynx before dividing into their respective tracts. The mouth is not listed as an
answer choice, so the correct answer is (B). A common passage for both food and
air is the pharynx.
