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  2. 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 ...

  3. Xylem - Wikipedia

    en.wikipedia.org/wiki/Xylem

    Different plant species can have different root pressures even in a similar environment; examples include up to 145 kPa in Vitis riparia but around zero in Celastrus orbiculatus. [ 13 ] The primary force that creates the capillary action movement of water upwards in plants is the adhesion between the water and the surface of the xylem conduits.

  4. Phloem loading - Wikipedia

    en.wikipedia.org/wiki/Phloem_loading

    Thus, plants with a lot of plasmodesmata are generally passive loaders. Plants with few or absent plasmodesmata are usually active loaders since they do not have a way for solutes to pass through the symplast. [3] In 2001, Robert Turgeon and colleagues found that plasmodesmatal frequency is not the sole indicator of a plant's phloem-loading ...

  5. Phloem - Wikipedia

    en.wikipedia.org/wiki/Phloem

    Phloem (/ ˈ f l oʊ. əm /, FLOH-əm) is the living tissue in vascular plants that transports the soluble organic compounds made during photosynthesis and known as photosynthates, in particular the sugar sucrose, [1] to the rest of the plant. This transport process is called translocation. [2]

  6. Mass flow (life sciences) - Wikipedia

    en.wikipedia.org/wiki/Mass_flow_(life_sciences)

    As such, mass flow is a subject of study in both fluid dynamics and biology. Examples of mass flow include blood circulation and transport of water in vascular plant tissues. Mass flow is not to be confused with diffusion which depends on concentration gradients within a medium rather than pressure gradients of the medium itself.

  7. 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.

  8. Polar auxin transport - Wikipedia

    en.wikipedia.org/wiki/Polar_auxin_transport

    Polar auxin transport (PAT) is directional and active flow of auxin molecules through the plant tissues. The flow of auxin molecules through the neighboring cells is driven by carriers (type of membrane transport protein) in the cell-to-cell fashion (from one cell to other cell and then to the next one) and the direction of the flow is determined by the localization of the carriers on the ...

  9. Transcellular transport - Wikipedia

    en.wikipedia.org/wiki/Transcellular_transport

    There are two types of active transport, primary active transport and secondary active transport. [citation needed] Primary active transport uses adenosine triphosphate (ATP) to move specific molecules and solutes against its concentration gradient. Examples of molecules that follow this process are potassium K +, sodium Na +, and calcium Ca 2+.