Phosphorus is: added to the soil through weathering
usually very abundant in an ecosystem
returned to the soil by rhizobium
found free in the atmosphere

Now it's your turn to investigate human impact around the world. grab your virtual lab coat and put on your environmental science hat. you will be taking a trip around the globe to explore three locations. at each location, you will investigate the cause and effect relationships of deforestation, desertification, and urbanization. you will also gather evidence of how these factors have impacted the environment over time

When a person is exercising the body needs to deliver increased amounts of oxygen to the muscles which component of blood ensures that the muscles will receive it

Blood stem cells may develop into any kind of human blood cells. what kind of stem cells are blood stem cells? a. multipotent stem cells o b. totipotent stem cells o c. pluripotent stem cells o d. unipotent stem cells