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  2. Absorption of water - Wikipedia

    en.wikipedia.org/wiki/Absorption_of_water

    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 ...

  3. Active transport - Wikipedia

    en.wikipedia.org/wiki/Active_transport

    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 ...

  4. Absorption (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Absorption_(chemistry)

    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 ...

  5. Membrane transport protein - Wikipedia

    en.wikipedia.org/wiki/Membrane_transport_protein

    Active transport is the movement of a substance across a membrane against its concentration gradient. This is usually to accumulate high concentrations of molecules that a cell needs, such as glucose or amino acids. If the process uses chemical energy, such as adenosine triphosphate (ATP), it is called primary active transport.

  6. Lipinski's rule of five - Wikipedia

    en.wikipedia.org/wiki/Lipinski's_Rule_of_Five

    Lipinski's rule of five, also known as Pfizer's rule of five or simply the rule of five (RO5), is a rule of thumb to evaluate druglikeness or determine if a chemical compound with a certain pharmacological or biological activity has chemical properties and physical properties that would likely make it an orally active drug in humans.

  7. Water activity - Wikipedia

    en.wikipedia.org/wiki/Water_activity

    The definition of a w is where p is the partial water vapor pressure in equilibrium with the solution, and p* is the (partial) vapor pressure of pure water at the same temperature. An alternate definition can be a w ≡ l w x w {\displaystyle a_{w}\equiv l_{w}x_{w}} where l w is the activity coefficient of water and x w is the mole fraction of ...

  8. Adsorption - Wikipedia

    en.wikipedia.org/wiki/Adsorption

    The adsorption rate is dependent on the temperature, the diffusion rate of the solute (related to mean free path for pure gas), and the energy barrier between the molecule and the surface. The diffusion and key elements of the adsorption rate can be calculated using Fick's laws of diffusion and Einstein relation (kinetic theory) .

  9. Biosorption - Wikipedia

    en.wikipedia.org/wiki/Biosorption

    Though bioaccumulation and biosorption are used synonymously, they are very different in how they sequester contaminants: . Biosorption is a metabolically passive process, meaning it does not require energy, and the amount of contaminants a sorbent can remove is dependent on kinetic equilibrium and the composition of the sorbents cellular surface. [9]