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  2. Active transport - Wikipedia

    en.wikipedia.org/wiki/Active_transport

    Active transport often takes place in the internal lining of the small intestine. Plants need to absorb mineral salts from the soil or other sources, but these salts exist in very dilute solution. Active transport enables these cells to take up salts from this dilute solution against the direction of the concentration gradient.

  3. Electron transport chain - Wikipedia

    en.wikipedia.org/wiki/Electron_transport_chain

    An electron transport chain (ETC [1]) is a series of protein complexes and other molecules which transfer electrons from electron donors to electron acceptors via redox reactions (both reduction and oxidation occurring simultaneously) and couples this electron transfer with the transfer of protons (H + ions) across a membrane.

  4. Transcellular transport - Wikipedia

    en.wikipedia.org/wiki/Transcellular_transport

    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).

  5. Exocytosis - Wikipedia

    en.wikipedia.org/wiki/Exocytosis

    Exocytosis (/ ˌ ɛ k s oʊ s aɪ ˈ t oʊ s ɪ s / [1] [2]) is a form of active transport and bulk transport in which a cell transports molecules (e.g., neurotransmitters and proteins) out of the cell (exo-+ cytosis). As an active transport mechanism, exocytosis requires the use of energy to transport material. Exocytosis and its counterpart ...

  6. Ion transporter - Wikipedia

    en.wikipedia.org/wiki/Ion_transporter

    Diffusion vs. Transport. In biology, an ion transporter is a transmembrane protein that moves ions (or other small molecules) across a biological membrane to accomplish many different biological functions, including cellular communication, maintaining homeostasis, energy production, etc. [1] There are different types of transporters including pumps, uniporters, antiporters, and symporters.

  7. Calcium pump - Wikipedia

    en.wikipedia.org/wiki/Calcium_pump

    They are responsible for the active transport of calcium out of the cell for the maintenance of the steep Ca 2+ electrochemical gradient across the cell membrane. Calcium pumps play a crucial role in proper cell signalling by keeping the intracellular calcium concentration roughly 10,000 times lower than the extracellular concentration. [1]

  8. Solute pumping - Wikipedia

    en.wikipedia.org/wiki/Solute_pumping

    Solute pumping is a form of active transport of a solute through a cell membrane.Solute pumping allows a molecule that cannot regularly cross the lipid bilayer (because of concentration gradient, polarity, or other reasons) to enter the cell by way of a protein channel.

  9. Active flow network - Wikipedia

    en.wikipedia.org/wiki/Active_flow_network

    [7] [8] Red blood cells are also transported inside these networks [9] and high pressure resistance could be due in part to red blood cell trafficking jam but also to capillary (largest pressure drops occur in the smallest vessels), especially in the brain. [10] [11] Blood flow is an active process further modulated by neuronal activity. [12]