What is the function of a phospholipid bilayer

Phospholipid bilayers create a selectively permeable barrier to the movement of ions and molecules important for cellular function.

The phospholipid bilayer acts as a barrier to the passage of molecules.

weathering - colorado river carves land in arizona to form the grand canyon. cracks form in a sandstone wall surrounding a house. a marble statue near the science museum is changing color due to rainfall

erosion - after a rainstorm, soil and rock piees litter the roadways. the sand dunes in the sahara desert are changing shape.

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