Nitrogen Cycle
How do humans get the nitrogen they need?
eating plants
What process returns carbon in dead organisms back to the atmosphere?
decomposition
What process converts carbon dioxide into sugar?
photosynthesis
What process returns carbon to the atmosphere through the process of burning?
combustion
What form is carbon found in in the carbon cycle?
carbon dioxide
How do plants get the nitrogen they need?
through their roots
Which process(es) remove(s) carbon from the atmosphere?
photosynthesis
Where in the plant does photosynthesis take place?
chloroplast
What types of organisms use cell respiration?
plants & animals
What is one thing that can be done to reduce the amount of CO2 in the atmosphere?
reduce burning of fossil fuels, increase amount of plants
After an organism dies, what happens to the nitrogen in its body?
recycled back into the soil
If more factories are built, what effect will this have on the atmosphere?
more carbon dioxide released
Why does respiration take place?
release energy from the cell
Place the following steps in order:
1. The chemical energy in sugar is used to help the plant grow.
2. Light energy enters plant cells.
3. Light energy is converted into chemical energy in the form of sugar.
4. Excess sugar is stored in the plant until needed.
2, 3, 1, 4
As the nitrogen level in a lake increases, what happens to the algae growth?
increases
What is nitrogen fixation?
Bacteria take the nitrogen in the air and change it to a form plants can use.
Raking leaves prevents what from happening?
carbon being returned to the soil
A plant is placed underwater under a light. Bubbles come out from the plant. What are these bubbles made of?
oxygen
What is a negative effect of fertilizer?
too much can lead to an algal bloom
What is a positive effect of using fertilizer?
helps plants grow
Why is crop rotation important?
It allows plants like legumes to put nitrogen back into the soil.
A person exhales during cell respiration. Where would the carbon dioxide they exhale end up due to photosynthesis?
part of a plant
What three factors affect photosynthesis and how?
The more light the more photosynthesis.
The more carbon dioxide the more photosynthesis.
It only works in certain temperature ranges.
What is the equation for cell respiration?
C6H12O6 + 6O2 --> 6CO2 + 6H2O + energy
What is the formula for photosynthesis?
energy + 6CO2 + 6H2O --> C6H12O6 + 6O2