Answer:
The respiratory system works directly with the circulatory system to provide oxygen to the body. The primary function of the respiratory system is to deliver oxygen to the cells of the body's tissues and remove carbon dioxide, a cell waste product.Respiratory systems work together to circulate blood and oxygen throughout the body.The respiratory system subdivides into a conducting portion and a respiratory portion. The majority of the respiratory tree, from the nasal cavity to the bronchi, is lined by pseudostratified columnar ciliated epithelium. The bronchioles are lined by simple columnar to the cuboidal epithelium, and the alveoli possess a lining of thin squamous epithelium that allows for gas exchange.The conducting piece of the respiratory system consists of the nasal cavity, trachea, bronchi, and bronchioles. The luminal surfaces of this entire portion have a lining of ciliated pseudostratified columnar epithelium and contain goblet cells. Their role is to secrete mucus that serves as the first line of defense against incoming environmental pathogens. Cilia move the mucus-bound particulate up and away for expulsion from the body. The various types and abundance of cells are dependent on which region of the airway they are.