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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. Transcellular transport - Wikipedia

    en.wikipedia.org/wiki/Transcellular_transport

    Passive transport is the process of moving molecules from an area of high concentration to an area of low concentration without expelling any energy. There are two types of passive transport, passive diffusion and facilitated diffusion.

  4. Membrane transport - Wikipedia

    en.wikipedia.org/wiki/Membrane_transport

    These proteins can be involved in transport in a number of ways: they act as pumps driven by ATP, that is, by metabolic energy, or as channels of facilitated diffusion. Transport of substances across the plasma membrane can be via passive transport (simple and facilitated diffusion) or active transport.

  5. Membrane transport protein - Wikipedia

    en.wikipedia.org/wiki/Membrane_transport_protein

    Powered by ATP, the pump moves sodium and potassium ions in opposite directions, each against its concentration gradient. In a single cycle of the pump, three sodium ions are extruded from and two potassium ions are imported into the cell. Active transport is the movement of a substance across a membrane against its concentration gradient. This ...

  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. Glucose uptake - Wikipedia

    en.wikipedia.org/wiki/Glucose_uptake

    The two ways in which glucose uptake can take place are facilitated diffusion (a passive process) and secondary active transport (an active process which on the ion-gradient which is established through the hydrolysis of ATP, known as primary active transport). Active transport is the movement of ions or molecules going against the ...

  8. Symporter - Wikipedia

    en.wikipedia.org/wiki/Symporter

    Comparison of transport proteins. A symporter is an integral membrane protein that is involved in the transport of two (or more) different molecules across the cell membrane in the same direction. The symporter works in the plasma membrane and molecules are transported across the cell membrane at the same time, and is, therefore, a type of ...

  9. Electrochemical gradient - Wikipedia

    en.wikipedia.org/wiki/Electrochemical_gradient

    Since the ions are charged, they cannot pass through cellular membranes via simple diffusion. Two different mechanisms can transport the ions across the membrane: active or passive transport. [citation needed] An example of active transport of ions is the Na +-K +-ATPase (NKA).