All cells have an outer plasma membrane ... like oxygen and carbon dioxide cross membranes rapidly. Small polar molecules, such as water and ethanol, can also pass through membranes, but they do ...

Each component of a cell has its own function. Animal and plant cells differ and they have similarities. Nucleus, cell membrane ... fruits like apples. When they're well-watered, the vacuoles ...

But how do cells get ... to provide a cell with energy, these molecules have to pass across the cell membrane, which functions as a barrier — but not an impassable one. Like the exterior walls ...