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Active absorption refers to the absorption of water by roots with the help of adenosine triphosphate, generated by the root respiration: as the root cells actively take part in the process, it is called active absorption. According to Jenner, active absorption takes place in low transpiring and well-watered plants, and 4% of total water ...
There are two types of active transport: primary active transport that uses adenosine triphosphate (ATP), and secondary active transport that uses an electrochemical gradient. This process is in contrast to passive transport , which allows molecules or ions to move down their concentration gradient, from an area of high concentration to an area ...
Absorption is the journey of a drug travelling from the site of administration to the site of action. [ 1 ] [ 2 ] The drug travels by some route of administration ( oral , topical-dermal , etc.) in a chosen dosage form (e.g., tablets , capsules , or in solution ). [ 3 ]
Secondary active transport is when one solute moves down the electrochemical gradient to produce enough energy to force the transport of another solute from low concentration to high concentration. [citation needed] An example of where this occurs is in the movement of glucose within the proximal convoluted tubule (PCT).
A more common definition is that "Absorption is a chemical or physical phenomenon in which the molecules, atoms and ions of the substance getting absorbed enter into the bulk phase (gas, liquid or solid) of the material in which it is taken up." A more general term is sorption, which covers absorption, adsorption, and ion exchange. Absorption ...
Hence reabsorption of glucose is dependent upon the existing sodium gradient which is generated through the active functioning of the Na + /K +-ATPase. As the cotransport of glucose with sodium from the lumen does not directly require ATP hydrolysis but depends upon the action of the ATPase, this is described as secondary active transport.
The term sorption encompasses both adsorption and absorption, and desorption is the reverse of sorption. IUPAC definition adsorption : An increase in the concentration of a dissolved substance at the interface of a condensed and a liquid phase due to the operation of surface forces.
Activated carbon. Activated carbon, also called activated charcoal, is a form of carbon commonly used to filter contaminants from water and air, among many other uses. It is processed (activated) to have small, low-volume pores that greatly increase the surface area [1] [2] available for adsorption or chemical reactions. [3]