noun, plural: absorptions
The process of absorbing or assimilating substances into cells or across the tissues and organs through diffusion or osmosis, as in absorption of nutrients by the digestive system, or absorption of drugs into the bloodstream
Absorption, in general sense, is the act or process of absorbing or assimilating. In biology, absorption pertains particularly to the process of absorbing or assimilating substances into the cell or across the tissues and organs. It is done through diffusion or osmosis. For instance, absorption through the skin is a way through which substances can enter the body. Referred to as dermal absorption, the process of absorbing upon exposure to certain toxic substances is one of the means (others, via inhalation and ingestion) through which they could enter the body. Dermal absorption may also be used as a route of administration for certain medications. Another example of biological absorption is the absorption of digested food specifically through the wall of the intestine (especially, the small intestine). The digested food in the small intestine passes through the walls of the small intestine into the blood vessels by diffusion or by active transport.
In other related disciplines, such as physics, absorption refers to the act or process of retaining light energy without reflection or transmission upon passing through a medium, as in the absorption of light by atoms. In chemistry, absorption pertains to the process in which a substance permeates another, as in a liquid permeating, or absorbed by, a solid.
Word origin: Latin absorptio, from absorbere
- absorption band
- absorption cell
- atomic absorption spectrophotometry
- cutaneous absorption
- external absorption
- linear absorption coefficient
- specific absorption coefficient