Regarding the Na K ATPase pump Question 11 options A Na and

Regarding the Na+ - K+ ATPase pump: Question 11 options: A. Na+ and Mg2+ are required for dephosphorylation of the phosphorylated enzyme. B. K+ is required for phosphorylation of the enzyme by ATP. C. Both D. Neither

Solution

Answer: D. Neither

Reason:

The movements of this Na+, k+ ions are mainly relied upon the phosphorylation trigger din the presence of “Mg2+” so that it is possible via phosphorylation using ATP in the presence of Na+ and Mg2+ through “Na+-K+ ATPase enzyme. The K+ ions are going to mediate dephosrylation so that higher affinity for Na+ ions. In a living cell, normally the inner concentration of K+ inside the cell is higher therefore exerts “negative charge’ with resting membrane potential -55mV to -70mV. Now, when excitatory post synaptic potential is going to act on the cell membrane, depolarization triggered in case of Na+-K+ ATPase channels to open Na+ channels to allow “more positive charged ( because both electrical & concentration gradients of sodium tends to drive sodium into the cell)” sodium into the cells now attains a threshold +10mV. This is going to trigger opening of K+ channels to allow, “potassium (K+) positive ions into the cell due to electrical gradient” whereas the “concentration gradient tends to allow the movement of potassium out of cell” combine representing electrochemical gradient.