ATP animation

In the figure below is depicted a membrane and an integral membrane protein called a Na+-K+ ATPase.

In the figure are two triangles that indicate concentration gradients of Na+ and K+ across the membrane.

The Na+-K+ ATPase will transport Na+ ions against its concentration gradient and K+ ions against its concentration gradient.




The series of steps depicted below are as follows:

The figure below represents a sequence of events that occur with the same protein over a period of time

Step 1


3 Na+ ions bind to the ATPase under conditons of low Na+ concentrations because ATP andthe transport protein has a high affinity for Na+. This means the protein will bind Na+ ions even when the Na+ concentration is low Mg++ bind to the protein . These are exergonic reactions