The current thought on the structure of the cell membrane is: a. a static phosphate sandwich of lipids b. a fluid-mosaic of phospholipids and proteins c. a bilayer of proteins with static lipid molecules d. an impermeable bilayer of protein molecules e. a static and permeable phospholipid single layer

b. a fluid-mosaic of phospholipids and proteins

Explanation:

According to the currently accepted structure, the cell membrane is made up of two layers of amphipathic phospholipids in which proteins are embedded or present. The hydrophobic tails of phospholipids make the core of the membrane. These tails are not covalently attached to each other and are free to move laterally. Likewise, the protein molecules float in the fluid bilayer. This mosaic pattern is not static since the positions of the proteins in the bilayer are constantly changing. The fluid mosaic model to explain the structure of the cell membrane was given by S.J. Singer and Garth L. Nicolson in 1972.

a- all cells come from pre-existing cells

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