After reaching the pharynx, air travels towards the larynx, otherwise known as the voice box, which contains the vocal cords which vibrate to produce sound. Above the larynx is the epiglottis which is a flap that can close to block food and liquid from going through the respiratory tract when a person swallows. The epiglottis covers the next part of the respiratory system, which is the windpipe or the trachea. The trachea can be distinguished by its stiff C-shaped rings of cartilage, which reinforce it to prevent it from collapsing and to keep the airways open. Much like the nasal cavities, the trachea is also lined with its own cilia, but with a substance called ciliated pseudostratified columnar epithelium which secretes mucus to protect the trachea from harmful matter. This mucus is removed from the body through coughing, sneezing, spitting, or even
After reaching the pharynx, air travels towards the larynx, otherwise known as the voice box, which contains the vocal cords which vibrate to produce sound. Above the larynx is the epiglottis which is a flap that can close to block food and liquid from going through the respiratory tract when a person swallows. The epiglottis covers the next part of the respiratory system, which is the windpipe or the trachea. The trachea can be distinguished by its stiff C-shaped rings of cartilage, which reinforce it to prevent it from collapsing and to keep the airways open. Much like the nasal cavities, the trachea is also lined with its own cilia, but with a substance called ciliated pseudostratified columnar epithelium which secretes mucus to protect the trachea from harmful matter. This mucus is removed from the body through coughing, sneezing, spitting, or even