Gas exchange is the physical process by which gases move passively by diffusion across a surface. For example, this surface might be the air/water interface of a water body, the surface of a gas
Gas exchange is the process of absorbing inhaled atmospheric oxygen molecules into the bloodstream and offloading carbon dioxide from the bloodstream into the atmosphere. This process is completed in the lungs through the diffusion of gases from areas of high concentration to areas of low concentration.
Levels of organization in ecology include the population, community, ecosystem, and biosphere. An ecosystem is all the living things in an area interacting with all of the abiotic parts of the environment.
