NEET BIOLOGY

Detailed explanation-1: -Proteins embedded within the phospholipid bilayer carry out the specific functions of the plasma membrane, including selective transport of molecules and cell-cell recognition.

Detailed explanation-2: -The cell membrane controls what goes in and out by having protein channels that act like funnels in some cases and pumps in other cases. Passive transport does not require energy molecules and happens when a funnel opens in the membrane, letting molecules flow through.

Detailed explanation-3: -The simplest mechanism by which molecules can cross the plasma membrane is passive diffusion. During passive diffusion, a molecule simply dissolves in the phospholipid bilayer, diffuses across it, and then dissolves in the aqueous solution at the other side of the membrane.

Detailed explanation-4: -The plasma membrane is the border between the interior and exterior of a cell. As such, it controls passage of various molecules-including sugars, amino acids, ions, and water-into and out of the cell.

Detailed explanation-5: -Cell membranes are selectively permeable, regulating which substances can pass through, as well as how much of each substance can enter or exit at a given time.