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Na+/K+ channels maintain the resting potential with other sodium and potassium channels. Then what are these "Leak" channels? are they the same Na+/K+ pump in a special condition? If so, what is it?Source: Guyton and Hall- Textbook of Medical Physiology

Source of Image: Guyton and Hall- Textbook of Medical Physiology

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    $\begingroup$ Pumps are active transporters, channels are passive. They're different proteins altogether. $\endgroup$ – AliceD Jan 6 '17 at 16:44
  • $\begingroup$ @Christiaan my doubt is that the image shows same/similar proteins. What are they? Same or similar? $\endgroup$ – YAHB Jan 6 '17 at 16:46
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    $\begingroup$ I agree with @Christiaan because there is a huge difference between a pump and a channel. If you want to check the difference you can simply google it or check what the wiki says about that difference. $\endgroup$ – The_Mad_Fish Jan 6 '17 at 17:30
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Below is the structure of a Na+/K+ ATPase, i.e., the sodium/potassium pump shown on the left in your figure:

Na+/K+ ATPase

(image from here)

Compare to the structure of a potassium leak channel (the type of channel depicted on the right in your question):

2-pore potassium channel

(see this publication; image from here)

It's clear they are quite different beasts, without much similarity at all besides both being membrane proteins with several transmembrane domains, which is a characteristic they share with countless other proteins with an incredibly wide range of functions.

The only similarity the pictures from your textbook are meant to convey is that they are both membrane-bound proteins and that they accommodate Na+ and K+; besides that, they are completely different. The figure clearly shows a different mechanism of transport, and the remaining similarity is just from the very abstract way that they are represented.

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