Which sentence or sentences elaborate by showing a cause and effect?
Say you are sitting still. Then you decide to hop on your skateboard.
In an instant, the motor area of your brain gets busy sending signals via the nerve cells and other transmitters. The result is a
contraction of muscle.
Of course, you don't decide on every movement you make. You don't have to decide to breathe or swallow your food.
Did you know that each time you smile, frown, or chew and swallow a bite of food you are using your muscles?
