The ratio of ions moving out of the cell to the no. of ions moving inside the cell via the na:k ATPase pump is?
**Core Concept**
The sodium-potassium pump (Na+:K+ ATPase) is an enzyme that maintains the resting membrane potential by transporting sodium ions (Na+) out of the cell and potassium ions (K+) into the cell against their concentration gradients. This process requires energy from ATP hydrolysis.
**Why the Correct Answer is Right**
The sodium-potassium pump transports 3 Na+ ions out of the cell and 2 K+ ions into the cell for each ATP molecule hydrolyzed. This ratio of 3:2 is crucial for maintaining the proper ion balance and membrane potential. The pump's activity is essential for various cellular functions, including nerve impulse transmission and muscle contraction. The Na+:K+ ATPase pump is also sensitive to cardiac glycosides, which can inhibit its activity and increase intracellular Na+ and Ca2+ concentrations.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately reflect the 3:2 ratio of Na+:K+ ions transported by the pump.
**Option B:** This option is incorrect because it inverts the ratio, suggesting that the pump transports 2 Na+ ions out and 3 K+ ions in, which is not the case.
**Option C:** This option is incorrect because it does not specify a correct ratio of Na+:K+ ions transported by the pump.
**Clinical Pearl / High-Yield Fact**
The sodium-potassium pump is essential for maintaining the resting membrane potential and is sensitive to cardiac glycosides, which can have significant effects on cardiac function and rhythm.
**Correct Answer:** C. 3:2