(2) A motor neuron in the ventral horn of the spinal cord is activated, and an action potential passes outward in a ventral root of the spinal cord. (3) The axon branches to supply a number of muscle fibers called a motor unit, and the action potential is conveyed to a motor end plate on each muscle fiber.
The average male height varies from country to country. The estimated average height for the human male across the world is approximately 5ft 8 1/2in (1.73 m.) According to John Komlos of the University of Munich, North Americans were the tallest people on the planet from about the American Revolution to World War II.
That's a little over an inch shorter than the average height of adult men today. Even earlier reports of the average height of men in the United States include that: 1  Pilgrim men probably averaged about 66 inches (1620) 2  Native Americans averaged 68 inches (1800s)  Civil War soldiers averaged 67.7 inches (1863)