AP BIOLOGY

Detailed explanation-1: -Osmosis is a special case of diffusion. Water, like other substances, moves from an area of higher concentration to one of lower concentration.

Detailed explanation-2: -Diffusion. During diffusion, substances move from an area of high concentration to an area of low concentration, until the concentration becomes equal throughout a space. Image showing the process of diffusion across the plasma membrane.

Detailed explanation-3: -Diffusion: Diffusion is the movement of particles from an area of higher concentration to lower concentration. The overall effect is to equalize concentration throughout the medium.

Detailed explanation-4: -In facilitated transport, also called facilitated diffusion, material moves across the plasma membrane with the assistance of transmembrane proteins down a concentration gradient (from high to low concentration) without the expenditure of cellular energy.

Detailed explanation-5: -ACTIVE TRANSPORT It is also possible to move substances across membranes against their concentration gradient (from areas of low concentration to areas of high concentration). Since this is an energetically unfavorable reaction, energy is needed for this movement. The source of energy is the breakdown of ATP.