An era is a commonly used word for a long period of time. When used in science, for example geology, an era denotes a clearly defined period of time of arbitrary but well-defined length, such as for example the Mesozoic Era from 252 Maâ66 Ma, delimited by a start event and an end event.
As you increase voltage to the muscle describe how it responds to the increased stimulus. As the voltage was increased from threshold to maximum voltage, there was a greater force in the muscle contraction. Once the maximum voltage (2500 mv) was reached, even if there was an increase in voltage, the force of the muscle contraction remained the same.
In order for a skeletal muscle contraction to occur; 1. There must be a neural stimulus. 2. There must be calcium in the muscle cells. 3. ATP must be available for energy. So, a few things can stop a contraction; 1. Energy system fatigue: There is no more ATP left in the muscle cell so it canât keep contracting.