Essay On Resting Membrane Potential

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There are billions of neurons in our brain that sends signals from the axon to the spinal cord. In the spinal cord the axon on will send signals to many neurons from other cells and then it will generate an order. The membrane potential is an electrical state of the cell membrane and it allows gradients that cause ions to move across the cell membrane. The dispersal of charge across the cell membrane is measured in (mV). The resting membrane potential is the difference between the charges inside and outside the sarcolemma. The intracellular concentration consists of sodium (Na+), potassium (K+), and Chlorine (Cl-). The concentration of potassium is high inside the cell and the concentration of sodium outside is high. The ion channels are watery pores in which ions can only cross through the neuron membrane (Pearson Cummings 2008). The ion channel is the control of movement of ions across the neuron membrane. There are leakage channels that are randomly gated which open and close anytime. The nervous system is selectively permeable which allows some cells to go in and out of the cell membrane. There are excitable cells …show more content…
The membrane potential is negative and all the potassium channels are closed due to the repolarization of potassium. The absolute refractory period occurs during repolarization and the muscle fibers cannot respond to a stimulus. The cell can regenerate anther action potential, but only id it is depolarized to a value more positive than the normal threshold. After the action potential is generated at the axon hillock it is then propagated down the axon. The other step is the action potential travels down the T-tubules. Then the action potential triggers the terminal cisternae to release calcium ions into the sarcoplasm. In sliding filament mechanism of contraction the relax state is when ATP binds to the myosin head and is cleaved into

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