Answer:
Explanation:
The pharynx is a five-inch long tube that starts near our nose and ends at our windpipe. The pharynx is generally considered a part of the throat in both vertebrate and invertebrate animals. In humans, it is a hollow structure (or muscular cavity) lined with moist tissue. This is typical of all structures within our alimentary and digestive tracts. Having a moist lining with a mucus rich barrier allows us both to breathe and for our food to travel safely through our canal without damaging our sensitive tissues. The muscular pharynx effectively forms the entry for the esophagus, or our “food canal,” and the trachea, also known as our “windpipe.” For this reason, the pharynx is considered a part of both our respiratory and digestive systems.FUNCTIOMAs mentioned before, the pharynx has roles in both the respiratory and digestive systems, and can be thought of as the point where these systems diverge. While food and liquids will follow the alimentary canal through the esophagus, the air we breathe in through that common entry point will enter the trachea and follow into the respiratory system.
The pharynx’s respiratory role is mainly to allow inhaled air entering the nasal cavity to make its way to the respiratory tract – which includes the larynx, the trachea or “windpipe” and finally the lungs’ bronchioles and alveoli where respiration takes place. This is made possible by the “isthmus” or structural common-space that connects the oral and nasal pharyngeal areas so that we are able to breathe through our mouths and noses.
The pharynx has an equally big digestive role thanks to its muscles. The constrictive circular muscles of the pharynx’s outer layer play a big role in peristalsis. A series of contractions will help propel ingested food and drink down the intestinal tract safely. The inner layer’s longitudinal muscles, on the other hand, will widen the pharynx laterally and lift it upward, thus allowing the swallowing of ingested food and drink.
An interesting role the pharynx also plays is in projecting speech. Sound is made possible by the passage of vibrations through air. The pharynx provides a nice enclosed space that will allow speech muscles to initiate sound and resonate it so that it projects even better.
