What is another name for the alveoli of the lungs?
Anatomy. However, alveoli are most often used to describe the small air sacs of the lungs of mammals, and are therefore known more specifically as the pulmonary alveoli. The pulmonary alveolus is a sac roughly 0.2 to 0.5 mm in diameter. These alveoli are located at the ends of air passageways in the lungs.
What is the function of Type II alveolar cells?
Type II pneumocytes. The type II alveolar cells (also known as type II pneumocytes) have two functions: (1) to repair the alveolar epithelium when squamous cells are damaged, and (2) to secrete pulmonary surfactant. Surfactant is composed of phospholipids and protein, and coats the alveoli and smallest bronchioles,…
What are the medical conditions that affect the alveoli?
Medical Conditions Affecting Alveoli. Tuberculosis is an infectious bacterial disease characterized by the growth of nodules in the tissues of the lungs. The disease primarily infects the alveoli as bacteria are inhaled, causing the formation of pus in the air sacs.
What is the pathway of air through the alveolus?
The oxygen-rich air travels down the trachea and then into one of the two lungs via the right or left bronchus. From there, the air is directed through smaller and smaller passages, called bronchioles, past the alveolar duct, until it finally enters an individual alveolus.
How much does lung size affect alveolar number?
Alveolar number was closely related to total lung volume, with larger lungs having considerably more alveoli. The mean size of a single alveolus was rather constant with 4.2 × 10 6 μm 3 (range: 3.3–4.8 × 10 6 μm 3; coefficient of variation: 10%), irrespective of the lung size.
How do you calculate alveolar number?
Alveolar number is estimated by counting their openings, which are regarded at the level of the free septal edges, where they form a two-dimensional network in three-dimensional space. Mathematically, the Euler number of this network is estimated using physical disectors at a light microscopic level.
What percentage of the alveolus is covered by alveolar cells?
The other 5% of the surface area of an alveolus is covered by round to cuboidal great (type II) alveolar cells. Although type II alveolar cells cover less surface area, they greatly outnumber the squamous alveolar cells.