Q4. The sodium-potassium pump moves sodium and potassium ions against the concentration gradient. 

1. True
2. False

Q5. The Na⁺-K⁺ pump consumes a third of the total ATP supply of a typical animal cell and is responsible for maintaining the high concentration of K⁺ inside cells, for controlling cell volume, and for driving the uptake of sugars and amino acids in the intestine and kidneys. 

1. True
2. False

Q6. The energy needed to power the sodium-potassium pump is provided by the 

1. Binding of ATP to the pump
2. Transport of ATP by the pump.
3. Splitting of ATP.
4. Formation of ATP.

Q7. Which of the following moves Ca²⁺ back into the tubules of the SR after a contraction? 

1. The ATP-dependent H⁺ pump
2. The ATP-dependent myosin pump
3. Simple diffusion
4. The ATP-dependent Na⁺/K⁺ pump
5. The ATP-dependent Na⁺/K⁺ pump
6. The ATP-dependent calcium pump

Q8. SERCS pumps actively transport calcium: 

1. From ER to cytosol
2. From cytosol to ER
3. From extracellular space to the cytosol
4. From the cytosol to the extracellular space
5. From the mitochondria to the cytosol