Cells -> Tissues -> Organs -> Organs systems -> Organisms
The Lithosphere is the layer of solid ground that makes up all of Earth’s continents. It is the <span>rigid, outermost shell of Earth.</span>
Don't pollute the Earth.
Don't need gas.
Permitting the exchange of nutrients and gases between the blood and tissue cells is the primary function of capillaries. Capillaries are the smallest blood vessels , they are only one cell thick, and they act as sites of the transfer of oxygen and other nutrients from the bloodstream to the body tissues. Additionally, they also collect carbon dioxide, waste materials and fluids for return to the veins.