MCQ
In which method of transport, plasma membrane does not require carrier molecule?
  • A
    Active transport
  • B
    Facilitated diffusion
  • Simple diffusion
  • D
    $Na ^+- K ^+$ pump

Answer

Correct option: C.
Simple diffusion
c
Simple diffusion is a process in which plasma membrane does not require any carrier molecule to pass small non- charged molecules or lipid soluble molecules between the phospholipids to enter or leave the cell. The particles move from areas of high concentration to areas of low concentration (they move down their concentration gradient). Oxygen and carbon dioxide and most lipids enter and leave cells by simple diffusion.

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