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Chapter 7 Membrane Structure and Function Overview: Life at the Edge the plasma membrane is the boundary that separates the living cell from its nonliving surroundings selectively permeable: allows some substances to cross it more easily than others Concept 7.1: Cellular membranes are fluid mosaics of lipids and proteins a phospholipid is an amphipathic molecule, meaning it has both hydrophilic and hydrophobic regions head composed of phosphate group attached to one carbon of glycerol two fatty acid tails are hydrophobic in the fluid mosaic model, the membrane is a fluid structure with a ?mosaic? of various proteins embedded in or attached to a bilayer of phospholipids Membrane Models: Scientific Inquiry phospholipids are the most abundant lipid in the plasma membrane

Chapter 12: The Cell Cycle Overview: The Key Roles of Cell Division the continuity of life is based upon the reproduction of cells, or cell division unicellular organisms reproduce by cell division multicellular organisms depend on cell division for development (from a fertilized cell), growth and repair the cell division process is an integral part of the cell cycle, the life of a cell from its formation from the division of the parent cell to its own division Concept 12.1: Cell division results in two identical daughter cells cells duplicate their genetic material before they divide, ensuring that each daughter cell receives an exact copy of genetic material, DNA Cellular Organization of the Genetic Material a cell?s endowment of DNA, its genetic information, is called its genome