Trachea the trachea. The trachea is no more than 4mm diameter during the first year of life, expanding to its adult diameter by late childhood. The trachea is more mobile and of more variable length, deeper, and smaller in children. The trachea is lined with a layer of pseudostratified ciliated columnar epithelium. The epithelium contains goblet cells, which are glandular, modified simple columnar epithelial cells that produce mucins, the main component of mucus. Mucus helps to moisten and protect the airways. Mucus lines the ciliated cells of the trachea to trap inhaled foreign particles that the cilia then waft upward toward
What Is Love? (EP) What Is Love? (EP) What Is Love? (stylized as What is Love?) is the fifth extended play (EP) by South Korean girl group Twice. The EP was released on April 9, 2018 by JYP Entertainment and is distributed by Iriver. It includes the lead single of the same name produced by Park Jin-young. Twice members Jeongyeon, Chaeyoung, and Jihyo also took part in writing lyrics for two songs on the EP. The reissue of "What Is Love?", titled "Summer Nights", was released on July 9, 2018. On February 26, 2018, JYP Entertainment confirmed that Twice planned to release a new