Question

(sodium potassum adenosine triphosphatase) is found in the plasma membrane and catalyzes the exchange of sodium and potassium ions across the membrane. Classify the statements about the transport system as either true or false.

Answer 1

The statements are:

Pumps K+ out of the cell False

Pumps K+ions into the cell True

Exchanges 3 Na+ ions for 2 K ions+ True

Exchanges 3 K+ ions for 2 Na+ ions False

Creates a membrane potential that is negative on the inside True

The transport protein becomes adenylated by ATP during the transport cycle True

Pumps Na+ ions out of the cell True

Pumps Na+ ions into the cell False

Explanation:

Sodium Potassium Adenosine Triphosphatase is in the membrane of cells. Its function is to create a difference of charges between the inside and the outside of the cell. The enzyme pumps 3 Na+ ions outside the cell for every 2 K+ ions that pumps inside the cell producing a resting potential. As this process is against their concentration gradient, the protein needs the energy to do it. This energy comes from the ATP that attaches to the transport protein.