Simple diffusion
Many alveoli-increases surface area for gas exchange Thin alveolar wall-allows gases to diffuse easily and fast Thin capillary wall-easy diffusion Inner wall of alveoli-allows gases to dissolve, which they need to enter the capillary
The thin barrier that allows for the efficient exchange of gases between the lungs and the blood is called the respiratory membrane. It consists of the alveolar walls, capillary walls, and their basement membranes. This structure is essential for the diffusion of oxygen and carbon dioxide during respiration.
Water uses capillary action to "climb" up plant vessels through cohesion and adhesion, which allows the water to be transported throughout the plant.
The alveolar region of the lungs. (alveoli)
The capillary action allows water to climb up sides of a straw due to adhesive forces.
Capillary
There are three major alveolar cell types in the alveolar wall (pneumocytes):* Type I cells that form the structure of an alveolar wall* Type II cells that secrete surfactant to lower the surface tension of water and allows the membrane to separate thereby increasing the capability to exchange gases.* Type III cells that destroy foreign material, such as bacteria.
It is the elasticity that keep alveolus in shape. However if it is deflated , surfactant avoid the alveolus from sticking to each other. Smooth muscle greatly hinder the efficiency of gas exchange as it thicken the diffusion surface. The alveoli consist of an epithelial layer and extracellular matrix surrounded by capillaries. In some The alveoli consist of an epithelial layer and extracellular matrix surrounded by capillaries. In some alveolar walls there are pores between alveoli called pores of Kohn. There are three major alveolar cell types in the alveolar wall (pneumocytes): * Type I (Squamous Alveolar) cells that form the structure of an alveolar wall * Type II (Great Alveolar) cells that secrete pulmonary surfactant to lower the surface tension of water and allows the membrane to separate, thereby increasing the capability to exchange gases. Surfactant is continuously released by exocytosis. It forms an underlying aqueous protein-containing hypophase and an overlying phospholipid film composed primarily of dipalmitoyl phosphatidylcholine. * Macrophages that destroy foreign material, such as bacteria.
pulmonary semilunar valve
The pulmonary artery is the main artery that carries blood to your lungs.
The pulmonic valve, a semilunar valve located between the right ventricle and the pulmonary trunk, opens to allow blood to flow into the pulmonary artery. This valve opens when the pressure in the right ventricle is greater than the pressure in the pulmonary artery, allowing blood to be pumped from the heart to the lungs for oxygenation.
Capillary action, due to the cohesive and adhesive properties of water, allows water to be pulled upward through the xylem tubes in plants. This mechanism, in combination with transpiration driven by evaporation from the leaves, helps move water from the roots to the tops of the trees.