AP BIOLOGY

Detailed explanation-1: -The membrane determines what solutes enter and leave a cell. Transmembrane transport is controlled by complex interactions between membrane lipids, proteins, and carbohydrates.

Detailed explanation-2: -Specialized proteins in the cell membrane regulate the concentration of specific molecules inside the cell. Membrane transport proteins are specific and selective for the molecules they move, and they often use energy to catalyze passage.

Detailed explanation-3: -Moving things in and out of the cell is an important role of the plasma membrane. It controls everything that enters and leaves the cell. There are two basic ways that substances can cross the plasma membrane: passive transport, which requires no energy; and active transport, which requires energy.

Detailed explanation-4: -A plasma membrane is permeable to specific molecules that a cell needs. Transport proteins in the cell membrane allow for selective passage of specific molecules from the external environment. Each transport protein is specific to a certian molecule (indicated by matching colors).