the segment of lung tissue that each tertiary bronchus supplies is called this.
each bronchial pulmonary segment of the lungs has many small compartments called these. Each is wrapped in elastic connective tissue and contains a lymphatic vessel, an arteriole, a venule, and a branch from a terminal bronchiole
terminal bronchioles subdivide into these microscopic branches
respiratory bronchioles subdivide into these
is a cup shaped out pouching lined by simple squamous epithelium and supported by a thin elastic basement membrane.
consists of two or more alveoli that share a common opening
Type one alveolar cells
are cells that form a nearly continuous lining of the alveolar walls. The site of gas exchange.
type 2 alveolar cells
also called septal cells are found in between type 1 alveolar cells. They have free surfaces containing microvilli, secrete alveolar fluid which keeps the surface between cells moist
contained in the alveolar fluid, is a complex mixture of phospholipids and lipoproteins. It lowers the surface tension of alveolar fluid, which reduces the tendency of alveoli to collapse
found in the alveolar wall, phagocytes that remove fine dust particles and other debris.
the exchange of O2 and C02 between the air spaces in the lungs and the blood takes place by diffusion across the alveolar and capillary walls, which together form this.
the process of gas exchange in the body
Pulmonary ventilation or breathing
is the inhalation and exhalation of air and involves the exchange of air between the atmosphere and the alveoli of the lungs
external pulmonary respiration
is the exchange of gases between the alveoli of the lungs and the blood in pulmonary capillaries across the respiratory membrane. In this process pulmonary blood gains o2 and loses co2.
internal (tissue) respiration
is the exchange of gases between blood in systemic blood capillaries and tissue cells. In this step the blood loses o2 and gains co2
the pressure of a gas in a closed container is inversely proportional to the volume of the container. If the size is increased the pressure of the gas decreases and if the size decreases the pressure increases.
the pressure between the two pleural layers in the pleural cavity. Just before inhalation it is 4 mmhg less than atmospheric pressure or about 756 mmhg
alveolar (intrapulmonic) pressure
the pressure inside the lungs, as the volume of the lungs increases, drops from 760 to 758 mmhg. A pressure difference is thus established between the atmosphere and the alveoli which we need for inhalation.
is also due to a pressure gradient. The pressure in the lungs is greater than in the atmosphere.
exhalation results from this. A recoiling of the chest wall and lungs both of which have a natural tendency to spring back after being stretched.
surface tension of alveolar fluid
exerted by a thin layer of alveolar fluid that coats the luminal surface of alveoli and exerts a force. this tension can be decreased by the presence of surfactant.
the ease with which the lungs and thoracic wall can expand.