Question

what is actually Flip flop movement and transition movemt of plasma membrane?

Answer 1

Although phospholipids and many proteins can move relatively freely and quickly along the lateral direction of the cell membrane, they find it much more difficult to move along the vertical direction. The movement of a molecule from one side of the membrane to the other is called transverse diffusion or flip flopping. Phospholipids can flip-flop but do so at a much lower rate than lateral diffusion. 

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