This gives them a rigid structure. Supports and strengthens cell? Cell membrane Selectively permeable double layer of lipid and protein molecules? All cell types ? Fluid enclosed by the cell ...

A plasma membrane is permeable to specific molecules that a cell needs. Transport proteins in the cell membrane allow for selective passage of specific molecules from the external environment.

Transport across membranes All cells are enclosed by a cell membrane, which is selectively permeable. Molecules can move into or out of cells by diffusion and active transport. Cells can gain or ...

The selectively ... permeable capillary wall, known as the glomerular filtration barrier (GFB), consists of three main ...