Biosphere Flashcards
What is the biosphere?
the layer around the earth containing all living organisms
What are biomes?
large regions of the world with distinctive climate, wildlife, and vegetation
What are the two main categories of biomes?
- terrestrial biomes
- aquatic biomes
What are the main terrestrial biomes?
-Tropical forest
-Boreal forest
Temperate forest
-Grassland (savanna)
-Arctic Tundra
-Deserts
-Alpine
What are the main Aquatic biomes?
freshwater:
- lakes
- rivers
-wetlands marine: -Estuaries -oceans and seas -coral reefs
What is a biogeochemical cycle?
a set of processes by which an element passes from one environment to the next and eventually returns to its original environment in an infinite loop of recycling.
What are the processes involved in biogeochemical cycles?
Biological:
- respiration
- digestion
Geological:
- erosion
- sedimentation
Chemical:
- combustion
- synthesis
What is the carbon cycle?
a biogeochemical cycle involving all the exchanges of carbon on earth
Why do living organisms use carbon?
to make up the skin and muscle tissues they are made of
What biogeochemical processes capture CO2?
- Photosynthesis
- shells and skeletons: CO2 dissolved in water reacts with calcium to make bones
What biogeochemical processes release CO2 into the atmosphere?
- Respiration
- Decomposition of waste
- forest fires (combustion)
- Volcanic eruptions
- combustion of fossil fuels
What is the nitrogen cycle?
biogeochemical cycle involving all the exchanges of nitrogen on earth
Why do living organisms use nitrogen?
to make their DNA and protein
What are the elements of the nitrogen cycle?
1) nitrogen fixation
2) nitrification
3) nitrogen absorption
4) decomposition of waste
5) denitrification
what is nitrogen fixation?
Bacteria takes nitrogen (NO2) from the air and transforms it into ammonia (NH3) and ammonium (NH$)
