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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

    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).

  4. 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.

  5. Passive transport - Wikipedia

    en.wikipedia.org/wiki/Passive_transport

    Passive diffusion across a cell membrane.. Passive transport is a type of membrane transport that does not require energy to move substances across cell membranes. [1] [2] Instead of using cellular energy, like active transport, [3] passive transport relies on the second law of thermodynamics to drive the movement of substances across cell membranes.

  6. DNA extraction - Wikipedia

    en.wikipedia.org/wiki/DNA_extraction

    DNA extraction is the process of isolating DNA from the cells of an organism isolated from a sample, typically a biological sample such as blood, saliva, or tissue. It involves breaking open the cells, removing proteins and other contaminants, and purifying the DNA so that it is free of other cellular components.

  7. Uniporter - Wikipedia

    en.wikipedia.org/wiki/Uniporter

    Facilitated diffusion may occur through three mechanisms: uniport, symport, or antiport. The difference between each mechanism depends on the direction of transport, in which uniport is the only transport not coupled to the transport of another solute. [4] Uniporter carrier proteins work by binding to one molecule or substrate at a time ...

  8. 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.

  9. Helicase - Wikipedia

    en.wikipedia.org/wiki/Helicase

    The size of the activation barrier to overcome by the helicase contributes to its classification as an active or passive helicase. In passive helicases, a significant activation barrier exists (defined as B > k B T {\displaystyle B>k_{\text{B}}T} , where k B {\displaystyle k_{\text{B}}} is the Boltzmann constant and T {\displaystyle T} is ...