Smooth muscle, such as in the digestive system, is also controlled by the autonomic nervous system. Like heart muscle, it is not under our conscious control. The SNS is responsible for controlling voluntary body movements, such as movement of the arms and legs.
The oceans cover 71 percent of the Earth's surface and contain 97 percent of the Earth's water. Less than 1 percent of the Earth's water is fresh water, and 2-3 percent is contained in glaciers and ice caps. The oceans contain 99 percent of the living space on the planet. If the ocean's total salt content were dried, it would cover the continents to a depth of 5 feet.
According to some figures, the consensus is that 70.8% of the Earth's surface is covered by water; 29.2 % is covered by land. Other figures suggest the percentage of Earth's surface covered by water is 71.11%; the percentage covered by land is 28.89%. Only 3% of that water is fresh water, the rest is saltwater. <br /> <b>The amount of Earth covered by water is exactly 71.13%</b> <br /> 70.78% of the Earth is covered in water. <br /> Land covers 29.22 percent of the Earth's surface. This is about 57.5 million square miles (149 x 106 square kilometers). Water covers the other 70.78 percent of the Earth's surface.