What is the circulation of carbon through the atmosphere, land, ocean, and living things called?
Carbon Cycle
When clouds get too heavy to hold water in the water cycle, what happens?
The water falls to the Earth
Why do living things need nitrogen?
to make protein
Where is most of the Earth's phosphorus stored?
Most phosphorus is stored in rocks, soil, and ocean sediments.
How do living things return carbon to the atmosphere and the ocean?
Respiration
Where is the purest water on Earth?
Glaciers and ice caps
What percentage of air is nitrogen?
79%
What is a key difference between the phosphorus cycle and the nitrogen or carbon cycle?
The phosphorus cycle does not have a significant atmospheric phase.
What type of organisms use carbon dioxide?
Plants and algae
What turns water on the Earth into vapor in the water cycle?
The sun
What is the process of converting atmospheric nitrogen into a usable form called?
Nitrogen fixation
How do plants get phosphorus from the environment?
Plants absorb dissolved phosphate from the soil through their roots.
What does respiration produce?
Energy, water, and carbon dioxide
Water that soaks into the ground is called what in the water cycle?
Groundwater
What is the name of the process where bacteria convert ammonia into nitrites and then nitrates?
This process is called nitrification
How is phosphorus returned to the soil after organisms die?
Decomposers, such as bacteria and fungi, break down dead organisms and waste, returning phosphorus to the soil.
How does carbon move from plants to animals?
Consumption
Condensation is when warm vapor rises, gets cold and does what In the water cycle?
Gathers in clouds
What is the most common way that nitrogen fixation occurs?
Nitrogen-fixing bacteria
What is the main way humans impact the phosphorus cycle?
Humans impact the cycle by using large amounts of phosphorus-rich fertilizers and detergents, which leads to runoff into waterways.