Which process refers to movement of water and solutes through the membrane by hydrostatic pressure?

Which process refers to movement of water and solutes through the membrane by hydrostatic pressure?

• A. Diffusion
• B. Osmosis
• C. Filtration
• D. Facilitated transport

Answer: (C)

Filtration is the process where hydrostatic pressure pushes water and small solutes through a membrane. When pressure on one side is higher, it forces fluid and dissolved substances to move through pores in the membrane, while larger molecules are left behind. This pressure-driven flow is what stat cortex uses in capillaries and in the kidneys to form filtrate. Contrast this with diffusion, which moves particles from high to low concentration due to random motion and doesn’t rely on pressure. Osmosis specifically describes water moving across a semipermeable membrane toward higher solute concentration, driven by osmotic gradients rather than direct hydrostatic pressure. Facilitated transport involves membrane proteins and usually moves substances along their concentration gradient without requiring hydrostatic pressure.

Filtration is the process where hydrostatic pressure pushes water and small solutes through a membrane. When pressure on one side is higher, it forces fluid and dissolved substances to move through pores in the membrane, while larger molecules are left behind. This pressure-driven flow is what stat cortex uses in capillaries and in the kidneys to form filtrate.

Contrast this with diffusion, which moves particles from high to low concentration due to random motion and doesn’t rely on pressure. Osmosis specifically describes water moving across a semipermeable membrane toward higher solute concentration, driven by osmotic gradients rather than direct hydrostatic pressure. Facilitated transport involves membrane proteins and usually moves substances along their concentration gradient without requiring hydrostatic pressure.