The reversal of charges in the membrane of cells e.g neuron cells results in electrical transmission.
Sodium diffuses in with the positive charges to replace the negatively charged internal environment of the neuron axon, to produce Action potential,provided that the deoplarisation produced by the reversal of charges is upto the threshold level.
The basis for the excitation of excitable cells is an electrical charge on the plasma membrane. The activity of the nervous system is reflected in a variety of electrical and chemical signals that arise in the receptor organs, the nerve cells and the effector organs, including the muscles and secretory glands. What literally happens is that the electrical charge difference (voltage) called the membrane potential, which occurs across the plasma membranes of all cells are generated by the passive diffusion of ions such as Na+, K+, Ca2+ and Cl− through highly selective molecular pores in the cell surface membrane called ion channels. As we all know that Ion channels play a role in membrane excitation as central as the role of enzymes in metabolism.
The opening and closing of specific channels shape the membrane potential changes and give rise to characteristic electrical messages.
Immature seed cones of conifers are usually green before pollination, and flowers of grasses are inconspicuously colored. What does this indicate about their pollination? they are wind pollinated.
