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Biology of the Cell Essay

For a nerve cell at its resting potential, the forces acting on potassium ions (K+) are: an electrical gradient, pulling K+ inward and a chemical gradient, pushing K+ outward. Suppose a cell’s membrane potential shifts from -move -numb. What changes in the cell’s permeability to K+ or An+ could cause a shift? An+ depopulating here. So we bring An+ ions into the cell. So to do this, you change membrane permeability by adding more An+ ion channels. To fill in and label the diagram.

Tell what the flow of potassium and sodium. Label Membrane potential (NV), Resting potential, Action potential, time mess. Explain deportation. Rising potential-more An going into the cell. Falling- Undershoot= potassium ion channels are still inactivated. So they would fall below the resting potential. Graded response vs. action potential-action potential is independent of the stimulus. Graded response potential is everything below the threshold. Things to know: what the threshold is. Intervention-more in the CANS.

Nervous system-point to point rapid deportation, the fall occurs due to the open of the voltage gate of potassium and closing of the sodium. Sodium potassium pump-resting potential Threshold is the deportation needed to activate

This phase takes place in the Rising phase. There is a build up of sodium ions. After the rise of the deportation, you have a fall of hyperventilation. The current is unidirectional because there is a closure of sodium. But they’re not Just closed, they’re inactivated. Because they’re inactivated, they can’t be reactivated at this time. They can’t be open at the same time of the deportation, which would keep the direction downward. It’s traveling down to the synaptic terminal. The speed of an action potential increases with the axon’s .

In vertebrates axons are insulated by a , which causes an action potentials speed to increase. They are small, which allows them to be bundled. The axial cell’s SCHUMAN cells (PENS) and the Electrodynamics of the CANS makes the myelin sheath. Nodes of envier-nodes speed up the reaction. Action potentials are formed only at the , gaps in the myelin sheath where voltage-gated An+ channels are found. Action potentials in militated axons Jump bit nodes of Rainier in a process called salutatory conduction.

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