creatinine is a normal waste product produced by muscle metabolism when your kidneys are functioning normally they filter creatinine and other waste products out of your blood and send them out of the body through urine
Tweet. This follows the page describing the basic anatomy of the lower respiratory tract. The term  tracheobronchial tree  or  respiratory tree  refers to the structures of bronchi and bronchioles that terminate with the alveolar ducts, sacs, and, finally, alveoli-that are contained within the lungs.herefore these structures are also referred to as  airways . This pages includes two diagrams of the airways-the main structure of the tracheobroncial tree being shown immediately below, and a second diagram showing the alveoli in further detail further down the page.
Superior vena cava. The lung consists of five lobes. The left lung has a superior and inferior lobe, while the right lung has superior, middle, and inferior lobes. Thin walls of tissue called fissures separate the different lobes. The superior lobes of each lung are the uppermost pieces, also called the upper lobes.Each lobe receives air from its own branch of the bronchial tree, called lobar (or secondary) bronchi. Within the lungs, these bronchi are divided into smaller tubes. The smallest of these tubes is called a bronchiole.he left lung has a superior and inferior lobe, while the right lung has superior, middle, and inferior lobes. Thin walls of tissue called fissures separate the different lobes. The superior lobes of each lung are the uppermost pieces, also called the upper lobes.