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Concentration Gradients and Diffusion quiz

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  • Why is there a concentration gradient of NaCl in the medulla?
    The concentration gradient of NaCl in the medulla is due to the active transport of ions, creating a difference in concentration between the medulla and surrounding areas, facilitating processes like osmosis.
  • What allows ions to diffuse down their electrochemical gradient across the membrane?
    Ions diffuse down their electrochemical gradient across the membrane due to the presence of specific ion channels that allow passive movement without requiring energy.
  • What is a concentration gradient?
    A concentration gradient is a difference in the concentration of a substance between two areas, where one area has a higher or lower concentration than another.
  • How do molecules move with their concentration gradient?
    Molecules move with their concentration gradient from an area of high concentration to an area of low concentration without requiring energy.
  • What is diffusion?
    Diffusion is the net movement of a substance from an area of high concentration to an area of low concentration, following the natural tendency of molecules to move down their concentration gradients.
  • What happens when a molecule moves against its concentration gradient?
    When a molecule moves against its concentration gradient, it goes from an area of low concentration to an area of high concentration, requiring energy.
  • What is equilibrium in the context of diffusion?
    Equilibrium in diffusion is when the concentration of a substance is evenly distributed throughout a space, with no net movement of molecules.
  • Why does diffusion not require energy?
    Diffusion does not require energy because it involves molecules moving down their concentration gradient, similar to a biker cruising downhill.
  • What role do ion channels play in diffusion?
    Ion channels facilitate the passive movement of ions down their electrochemical gradient across the membrane, allowing diffusion without energy.
  • How does active transport differ from diffusion?
    Active transport requires energy to move molecules against their concentration gradient, while diffusion is a passive process moving molecules down their gradient.