Water cycle
List all the steps of the water cycle.
Evaporation
condensation
precipitation
Runoff
Infiltration
Groundwater
How does nitrogen get from the atmosphere into the soil?
By nitrogen-fixing bacteria
What is the process called when plants use sunlight to make food from carbon dioxide?
Photosynthesis
Why do plants and animals need nitrogen?
To make proteins and DNA
How does groundwater become part of the water cycle?
It flows into rivers, lakes, or oceans, then evaporates
How can humans affect the phosphorus cycle?
By adding fertilizers to soil
What is a carbon sink?
A place that stores carbon
What is the role of bacteria in the nitrogen cycle?
They help change nitrogen into forms plants can use
How does the water cycle help keep ecosystems healthy?
By providing fresh water for plants and animals
Why is the phosphorus cycle different from the others?
It doesn’t have a gas phase in the atmosphere
What happens to carbon when plants and animals die?
It is returned to the soil and atmosphere by decomposers
How does nitrogen get from the atmosphere into the soil?
By nitrogen-fixing bacteria
Why is it important to study biogeochemical cycles?
To understand how nutrients move through Earth and support life
What is assimilation in plants?
Absorbing nutrients from soil
What is a “sink” in a biogeochemical cycle and why does it matter?
A place where elements are stored, helping control their movement in the cycle
What is one difference between the nitrogen cycle and the phosphorus cycle?
Nitrogen has a gas phase, phosphorus does not
What happens when there is too much algae in a lake?
Fish and other animals may die due to lack of oxygen
How can using too much fertilizer harm lakes or ponds?
It causes too much algae to grow
How do animals get the carbon and nitrogen they need to live?
By eating plants and other animals
What is eutrophication?
Too many nutrients causing algae to grow in water