Na+-K+ ATPase is which type of pump-
**Core Concept**
Na+-K+ ATPase is an electrogenic, transmembrane enzyme that pumps sodium ions out of the cell and potassium ions into the cell, utilizing energy from ATP hydrolysis to maintain the resting membrane potential and proper ion balance.
**Why the Correct Answer is Right**
Na+-K+ ATPase is a type of P-type ATPase, a class of enzymes that utilizes a phosphorylation-dephosphorylation cycle to drive ion transport across cell membranes. In this case, the enzyme phosphorylates a specific aspartate residue during the transport cycle, which is then dephosphorylated to complete the cycle. This enzyme is also known as the sodium-potassium pump.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect, as Na+-K+ ATPase is not a type of ABC (ATP-binding cassette) transporter, which uses a different mechanism to transport ions across cell membranes.
**Option B:** Incorrect, as Na+-K+ ATPase is not a type of V-type ATPase, which is primarily involved in acidification of cellular compartments.
**Option C:** Incorrect, as Na+-K+ ATPase is not a type of Ca2+-ATPase, which is involved in regulating calcium ion concentrations within the cell.
**Clinical Pearl / High-Yield Fact**
The sodium-potassium pump is an essential component of the resting membrane potential, and its dysfunction can lead to changes in membrane excitability, which can have significant clinical implications in conditions such as cardiac arrhythmias and muscle weakness.
**Correct Answer: D. P-type ATPase. Sodium-potassium pump.**