C. the birth rate increased
Wave of invader swept across Western Europe (Vikings, Franks, Goths, and Huns) trade slowed down to a trickle (people became more isolated) towns became empty, and classic learning just stopped.
Answer:
B) action potential
Explanation:
The ions continuously flow across the cell membrane in the cells which establishes a membrane potential across the membrane. The cell membrane tries to maintain the negative potential between -40 to -90 mV.
At rest the neuron cell maintains the membrane potential around -70mV and this potential are known as the resting potential.
When the positive ions especially sodium ions enter the neuron then the positive charges get accumulated inside the cell. This changes the potential to a more positive value and when it crosses the threshold of -55mV then an action potential is formed.
In the given question, if the membrane potential changes from –70 to +50mV then an action potential will be generated in the neuron cell.
Thus, B) action potential is the correct answer.
<span>If not all the facts have been discovered about a civilisation, society or event, historians have a difficult task describing it accurately and making sense of everything that happened.</span>
Answer: B? I'm not very sure but from my research I suppose it's this.
