Answer:
E. All of the above
Explanation:
In cardiac contractile cells there is rapid depolarization, then a plateau phase and repolarization.
when an action potential stimulates the cell, voltage-gated channels open quickly commencing the positive-feedback mechanism of depolarization. This in turn raises the membrane potential to approximately +30 mV, and this closes the sodium channels. Next comes the plateau phase, where membrane potential declines relatively slowly due to the opening of the slow Ca2+ channels, allowing Ca2+ to enter the cell while few K+ channels are open, leading to K+ to exit. Once the membrane potential reaches approximately zero, the Ca2+ channels close and K+ channels open, allowing the exit of K+. The repolarization lasts approximately for a while and here is when the membrane potential drops until it reaches resting levels once more and repeats the cycle.
Answer:
Enzymes are biological molecules that significantly speed up the rate of virtually all of the chemical reactions that take place within cells. They are vital for life and serve a wide range of important functions in the body, such as aiding in digestion and metabolism
Explanation:
Answer:
i am a bio student and still dont know the answer lol. i hate studies :/
Explanation:
