Answer:
I think the correct qnswer for this question is 50% but it is not given in the option so the correct answer is 30 %
Thank you.........
The dorsal surface in for legged animals is called superior
The right answer is <span>Refractory period.
At the moment when the action potential is emitted, the fiber being depolarized, it is impossible to depolarize it again. It is, therefore, necessary to wait until the membrane potential returns to a value below the critical threshold in order to be able to excite it again. We are thus led to distinguish two periods that characterize its excitability.
An absolute refractory period: during which any stimulation, even supraliminal, is ineffective since the fiber is already depolarized.
A relative refractory period: during which a second action potential can be omitted provided that the depolarization produced by the excitation reaches the critical threshold, which implies that it is more important since the value of the resting potential has not been restored yet.</span>
Answer:
1. Today instead of rotating upright, The earth's axis is tilted 23.5 degrees. The angle varies a little over time, but the gravitational pull of the moon prevents it from shifting by more than a degree so. This tilt is what gives us seasons.
2.The cooling effects of more indirect sunlight cause autumn and winter. Because of the earth's approximately 23.5° tilt, the season in the northern and southern hemispheres reversed, about six months apart from each other.