In cells, some molecules can move down their concentration gradients by crossing the lipid portion of the membrane directly, while others must pass through membrane proteins in a …

Diffusion is the movement of substances from a high to low concentration, while osmosis is the diffusion of water across a cell membrane that moves from high to low water potential (or, low …

Diffusion refers to the movement of molecules from an area of high concentration to an area of lower concentration. Osmosis is a type of diffusion specifically for water molecules moving …

Movement Across a Membrane and Energy There are two major ways that molecules can be moved across a membrane, and the distinction has to do with whether or not cell energy is …

Not everything enters the cell through passive transport. Only the smallest molecules like water, carbon dioxide, and oxygen can freely diffuse across cell membranes.

There are two main categories of passive transport: simple diffusion (sometimes called “diffusion”) and facilitated diffusion. Both types of passive transport involve substances moving across the …

If a cell is placed in a hypertonic solution, water will leave the cell, and the cell will shrink. In an isotonic environment, there is no net water movement, so there is no change in the size of the …

So, osmosis is a special case of facilitated diffusion. During osmosis in cells, water crosses the plasma membrane from an area of lower solute concentration to an area of higher solute …

Here, the cell can't import glucose for free using diffusion, because the natural tendency of the glucose will be to diffuse out rather than flowing in. Instead, the cell must bring in more …

Learn about the different types of diffusion, including transbilayer (flip-flop) and lateral, and the role of catalysts like flippase, floppase, and scramblase in these processes.