PPT2 Flashcards
What is Biology
The study of life
What is Geology?
The s
What is Geology?
The science which deals with the physical structure and substance of the earth, their history, and the processes which act on them.
What is Chemistry?
A branch of science that can be broken down into either “blowing stuff up” or “making drugs”
What are Global Cycles?
cycling of nutrients from the abiotic reservoirs to biotic reservoirs.
What is Nutrients?
are the elements and compounds that organisms need to live, grow, and reproduce.
What are Biogeochemical cycles?
move all nutrients through air, water, soil, rock and living organisms over millions of years
What are Nutrient Cycles?
Abiotic – nonliving cycles like rock cycle, water cycle and other chemical cycles.
Biotic – living organism involved cycles like carbon and nitrogen cycle.
All cycles enable a specific chemical element or nutrient to be taken and reused through various forms.
Where Carbon is stored?
Organic molecules – in living and dead organisms.
Carbon Dioxide (CO2) in atmosphere.
Organic matter in soil.
Fossil fuels and sedimentary rock like limestone.
CO2 in ocean/water bodies.
Calcium carbonate in the shells of marine organisms.
What is the major reservoir of carbon?
Atmosphere
Carbon in Atmosphere
Carbon dioxide gas exists in the atmosphere
It is dissolved in water for the sea gas exchange
Photosynthesis converts carbon dioxide gas to organic carbon
Respiration cycles the organic carbon back into carbon dioxide gas.
Volcanic activity is another way for carbon to enter the atmosphere from land (including land beneath the surface of the ocean). Carbon is released as carbon dioxide when a volcano erupts or from volcanic hydrothermal vents.
Human emissions bring this stored carbon back into the carbon cycle
Organic Carbon in Soil
Carbon stored in soil as organic carbon
Resulted from weathering of terrestrial rock and minerals
Organisms are performing respiration and cycles the organic carbon back into carbon dioxide gas (Respiration: a process in which organic molecules are broken down to release energy) . Organic carbon is also result of the decomposition of organisms
Deeper underground are fossil fuels, the anaerobically decomposed remains of plants and algae that lived millions of years ago.
this carbon can be leached into the water reservoirs by surface runoff
Carbon in the ocean
Carbon dioxide (CO2) from the atmosphere dissolves in water and reacts with water molecules to form ionic compounds
Some of these ions combine with calcium ions in the seawater to form calcium carbonate (CaCO3), a major component of the shells of marine organisms.
These organisms eventually die and their shells form sediments on the ocean floor.
Most of the carbon in the ocean is in the form of bicarbonate ions, which can combine with seawater calcium to form calcium carbonate (CaCO3),
More than 90 percent of the carbon in the ocean is found as bicarbonate ions.
Phosphorus Cycle
Weathering of rocks and volcanic activity releases phosphate into the soil, water, and air.
In remote regions, volcanic ash, aerosols, and mineral dust may also be significant phosphate sources.
It becomes available to terrestrial food webs.
Phosphate enters the oceans in surface runoff, groundwater flow, and river flow.
Phosphate dissolved in ocean water cycles into marine food webs.
Some phosphate from the marine food webs falls to the ocean floor, where it forms sediment.
The rock has its origins in the ocean. Phosphate-containing ocean sediments form primarily from the bodies of ocean organisms and from their excretions.
This sediment then is moved to land over geologic time by the uplifting of areas of the earth’s surface.
Excess phosphorus and nitrogen that enter these ecosystems from fertilizer runoff and from sewage cause excessive growth of algae
In addition to phosphate runoff as a result of human activity, natural surface runoff occurs when it is leached from phosphate-containing rock by weathering, thus sending phosphates into rivers, lakes, and the ocean.
The Nitrogen Cycle
(1) Nitrogen enters the living world from the
atmosphere via nitrogen-fixing bacteria.
(2) This nitrogen and nitrogenous waste from
animals is then processed back into gaseous
nitrogen by soil bacteria,
(3) Soil bacteria supply terrestrial food webs with
the organic nitrogen they need.
(4) Certain species of bacteria are able to
performnitrogen fixation
