If you have a well in your home, keep a close eye on the color of the water, which may tell you plenty about what might go on down under. If your well water turns an eerie blue or blue-greenish color, you have a problem related to either copper or zinc from bronze fixtures.
67 MembraneStructure andFunction Chapter Concepts 4.1 Plasma Membrane Structure and Function â¢ The plasma membrane regulates the passage ofmolecules into and out of the cell. 68â¢ The membrane contains lipids and proteins.
â¢ The plasma membrane functions as a selective barrier that allows the passage of oxygen, nutrients, and wastes for the whole volume of the cell. â¢ As a cell increases in size, its volume increases faster than its surface area. â As a result, smaller objects have a higher ratio of surface area to volume.