Capitol Report: Iranâs Global Threat. This week, I voted to stop the dangerous deal the Obama Administration negotiated to lift sanctions on Iran. I voted to protect Americans from the global threat posed by a nuclear Iran, because this is not a Republican issue or Democrat issue; this is an American security issue.
Cell Membrane. The cell membrane (plasma membrane) is a thin semi-permeable membrane that surrounds the cytoplasm of a cell. Its function is to protect the integrity of the interior of the cell by allowing certain substances into the cell, while keeping other substances out.
Lists of functions of a cell membrane (= plasma membrane) can include various numbers of functions because particles can move across the membrane in several different ways, including diffusion via ion channels, active transport via membrane pumps, endocytosis (into the cell) and exocytosis (out of the cell). The cell membrane forms a barrier between the inside of the cell and the environment outside the cell-enclosing cytoplasm and any organelles within the cell, and enabling different chemical environments to exist on each side of the cell membrane.