(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.
The average height of a North American adult female is 162 centimeters (5 feet 4 inches), and the average weight is 62 kilograms (137 pounds).. 1.62 m. (Female). In the 18th and 19th centuries, North American Indians and Europeans residing in that continent were the tallest in the world.he model predicts that adults born in 1820 achieved a mean adult height of 1.648 m; those born in 1952 reached 1.744 m; and those born in the year 200 are to reach on average an adult height of 1.783 m.