Transcript Biogeochemical Cycles

Ecology Unit:
Biogeochemical Cycles
Chapter 3.3
Biogeochemical Cycles
• Nutrients are passed between organisms and
the environment through biogeochemical cycles.
Why do living things need nutrients?
What if the nutrient is in short supply?
• If a nutrient is in short supply, it will limit the
organisms growth potential. This is a “limiting
nutrient.”
• 4 Nutrient Cycles:
Water, Carbon, Nitrogen, Phosphorus
Water Cycle Questions:
1. What are the 2 processes that allow water
to be released into the air?
Evaporation and transpiration
2. Water in gas form is turned into liquid form
by this process…
Precipitation
CO2 in
Atmosphere
CO2 in Ocean
Carbon Cycle Questions:
1. What process takes CO2 from the air?
Photosynthesis
2. What biotic process releases CO2 into the
air?
Cellular respiration
3. What kind of organisms can do the answer to
question #1?
Plants!
Figure 3-14 The Nitrogen Cycle
Section 3-3
Nitrogen Cycle Questions
1. Where do plants get their nitrogen from?
Nitrifying bacteria
2. Where do animals get their nitrogen from?
Eating plants
3. What organisms can “fix” gaseous nitrogen
from the air and put it in the soil?
Bacteria
4. What kind of bacteria can put nitrogen
back into the air?
Denitrifying bacteria
Phosphorous Cycle
1. Since phosphorous does not enter the
atmosphere, how do we get it?
Rocks and soil
2. Name a VERY important molecule we
need it for: Nucleic acids