They are semi-permeable, which means that some molecules ... transport chain and help generate energy for the cell. The double membrane enclosures of mitochondria and chloroplasts are similar ...

Like the exterior walls of a house, the plasma membrane is semi-permeable. In much the same way that doors and windows allow necessities to enter the house, various proteins that span the cell ...

They focused on the potential role of these cells' membrane, a semi-permeable barrier known to contribute to a cell's ...

the largest artery is the aorta Contain valves to prevent back flow of blood Walls are made of semi-permeable membrane to allow transport of gases and nutrients into and out of the blood Function ...