Sodium-Potassium Pump Specifics

Question 1

The process involves how many steps?

Answer 1

Six.

Question 2

Fill in the blanks.

First Step: ___ sodium ions bind to ___ sites on the sodium-potassium pump.

Answer 2

3 sodium ions bind to intracellular sites on the sodium-potassium pump

Question 3

Fill in the blanks.

Second Step: A ___ group is transferred to the pump via the ___ of ATP.

Answer 3

A phosphate group is transferred to the pump via the hydrolysis of ATP.

Question 4

Fill in the blanks.

Third Step: The pump undergoes a ___ change, translocating ___ across the membrane.

Answer 4

The pump undergoes a conformational change, translocating sodium across the membrane.

Question 5

Fill in the blanks.

Fourth Step: The ___ then exposes ___ potassium binding sites on the extracellular surface of the pump.

Answer 5

The conformational change exposes two potassium binding sites on the extracellular surface of the pump.

Question 6

Fill in the blanks.

Fifth Step: The ___ group is released which causes the pump to return to its ___.

Answer 6

The phosphate group is released which causes the pump to return to its original conformation.

Question 7

Fill in the blanks.

Sixth Step: This translocates the ___ across the membrane, completing the ion exchange.

Answer 7

This translocates the potassium across the membrane, completing the ion exchange.

Question 8

Identify what step.

Three sodium ions bind to intracellular sites on the sodium-potassium pump.

Answer 8

First

Question 9

Identify what step.

The pump undergoes a conformational change, translocating sodium across the membrane.

Answer 9

Third

Question 10

Identify what step.

A phosphate group is transferred to the pump via the hydrolysis of ATP.

Answer 10

Second

Question 11

Identify what step.

This translocate the potassium across the membrane, completing the ion exchange.

Answer 11

Sixth

Question 12

Identify what step.

The phosphate group is released which causes the pump to return to its original conformation.

Answer 12

Fifth

Question 13

Identify what step.

The conformational change exposes two potassium binding sites on the extracellular surface of the pump.

Answer 13

Fourth

Question 14

In simple terms, enumerate the steps of ion exchange:

Answer 14

1. Three sodium ions bind intracellularly.
2. Phosphate is transferred to the pump through hydrolysis of ATP.
3. Pump changes conformity, allowing sodium across.
4. The change in conformity exposes potassium-binding sites extracellularly.

5 and 6. Phosphate group is released, allowing the pump to return to its original conformity (shape).