Why is getting nitrogen into living organisms difficult?
Click to see answer
Plants and phytoplankton are not equipped to incorporate nitrogen from the atmosphere.
Click to see question
Why is getting nitrogen into living organisms difficult?
Plants and phytoplankton are not equipped to incorporate nitrogen from the atmosphere.
What do carbon compounds in fossil fuels contain?
Energy.
What drives the water cycle?
The Sun's energy as it warms the ocean and other surface water.
What is the Oxygen Cycle?
The circulation of oxygen in various forms through nature.
What is the process that leads to the evaporation of liquid surface water?
The Sun's energy warming the ocean and other surface water.
Why does life on Earth depend on the recycling of essential chemical elements?
Life on Earth depends on the recycling of essential chemical elements.
What process makes sulfates available to terrestrial ecosystems?
Weathering of rocks.
What event marked the beginning of the Industrial Revolution?
The demand for Earth’s limited fossil fuel supplies rising.
Where is the major reservoir of phosphorus found?
In sedimentary rocks of marine origin.
What is the solution phase in the sedimentary cycle related to?
Water.
What causes the formation of acid rain?
Rainwater falling to the ground through sulfur dioxide gas, turning it into weak sulfuric acid.
What happens as sulfur-containing rocks weather?
Sulfur is released into the soil.
In what form is atmospheric sulfur found?
Sulfur dioxide (SO2).
What is the process called when sulfur falls directly from the atmosphere?
Fallout.
What is transpiration?
The process of water movement through a plant and its evaporation from aerial parts.
Apart from sedimentary rocks, where else can large quantities of phosphorus be found?
In soils, dissolved in the oceans, and in organisms.
How does excess phosphorus and nitrogen enter the ecosystem?
Through fertilizer runoff and sewage.
What are some components in which phosphorus is found?
Nucleic acids, phospholipids, ATP, and other energy storing molecules.
What are the two interconnected sub-cycles of the carbon cycle?
One dealing with rapid carbon exchange among living organisms, and the other dealing with the long-term cycling of carbon through geologic processes.
What is desalination?
The process of removing mineral components from saline water.
What do plants and animals use oxygen for?
To respire and return it to the air and water as carbon dioxide (CO2).
What is the process of obtaining drinkable water from the ocean called?
Desalination.
How can human activity alter the nitrogen cycle?
By the combustion of fossil fuels, releasing nitrogen oxides.
What are nutrient cycles?
Important ecosystem processes that release matter necessary for life back into the environment and help sustain natural processes.
What is the major effect of fertilizer runoff on water bodies?
Eutrophication, which causes the overgrowth of algae, depletion of oxygen, and death of aquatic fauna.
How long did it take for fossil fuels to fossilize?
Millions of years.
Where does some phosphate leach into in the phosphorus cycle?
Groundwater and surface water, moving to the sea.
What is facilitated by biogeochemical cycles?
The transfer of molecules from one locality to another.
What is nitrogen fixation?
The process of converting nitrogen gas into ammonia (NH3), which spontaneously becomes ammonium (NH4+).
Where do the minerals ultimately settle out of circulation indefinitely?
Deep seas.
What is the name of the cycle involving sulfur and phosphorus?
Sedimentary Cycle.
What are the main components of the gaseous cycles?
Nitrogen, oxygen, carbon, and water.
What is happening to aquifers in many cases?
They are being depleted faster than they are being replenished by water penetrating down from above.
What is the process by which CO2 is converted into carbohydrates by algae and terrestrial green plants?
Photosynthesis.
What is eutrophication characterized by?
Excessive plant and algal growth.
What is the rock phase in the sedimentary cycle composed of?
Sediment.
How can human activity alter the nitrogen cycle?
By using artificial fertilizers in agriculture, which are then washed into lakes, streams, and rivers through surface runoff.
What are the forms in which water exists in the hydrophere?
Liquid water, beneath the surface, ice, and water vapor.
What are the three ways through which sulfur dioxide enters the atmosphere?
What process converts frozen water to water vapor by solar energy?
Sublimation.
What is a biogeochemical cycle?
A natural pathway by which essential elements of living matter are circulated.
What is the role of phosphate (PO4 3−) in the phosphorus cycle?
It is the only biologically important inorganic form, which plants absorb and use to synthesize organic compounds.
When do massive fish kills occur due to excess phosphorus and nitrogen?
During summer months.
What is the biological importance of water?
It is essential to all organisms.
What is the importance of carbon in biomolecules?
It is important in the structure of biomolecules.
What is the abundance ranking of oxygen among uncombined elements in the atmosphere?
Second only to nitrogen.
What is the product of condensation of atmospheric water vapor that falls on the ground?
Precipitation.
Where are sulfates returned to through the decomposition of living organisms?
The ocean, soil, and atmosphere.
Where do some salts dissolve and pass through a series of organisms?
In water.
What is the reservoir for sedimentary biogeochemical cycles?
Earth’s crust.
What is regulated by biogeochemical cycles?
The flow of substances.
Where does some phosphate from marine food webs end up?
It falls to the ocean floor, forming sediments.
Which parts of the plant are involved in transpiration?
Leaves, stems, and flowers.
What is the hydrophere?
The area of the Earth where water movement and storage occur.
Where does sulfur cycle between?
Between the oceans, land, and atmosphere.
How does nitrogen enter the living world from the atmosphere?
Via nitrogen-fixing bacteria.
What process gradually adds phosphate to the soil in the phosphorus cycle?
Weathering of rocks.
Where is oxygen found?
Free in the air and dissolved in water.
What are the two classifications of biogeochemical cycles?
Gaseous and Sedimentary.
How does the availability of water influence rates of ecosystem processes?
It influences the rates of ecosystem processes.
What are biogeochemical cycles?
Cycles that involve the movement of nutrients through biotic and abiotic components of ecosystems.
How are human actions affecting many of these cycles?
Human actions are now negatively affecting many of these cycles.
What process converts carbon dioxide gas to organic carbon?
Photosynthesis.
What is a major issue in modern times?
The supply of fresh water.
How does oceanic sulfur enter the ocean?
What are the main oxygen generators of the biosphere?
The waters of the world.
What is the role of sulfur in living things?
It is an essential element for the molecules of living things.
In what form is atmospheric sulfur found?
Sulfur dioxide (SO2).
What is estimated to replace about 90 percent of all oxygen used?
Algae.
What causes excessive plant and algal growth in eutrophication?
Increased availability of one or more limiting growth factors needed for photosynthesis.
Where do many of the carbon compounds in fossil fuels come from?
Dead plants and algae.
How does nitrogen enter the living world?
Through free-living and symbiotic bacteria.
What are the effects of atmospheric nitrogen associated with Earth's ecosystems?
Production of acid rain (as nitric acid, HNO3) and greenhouse effects (as nitrous oxide, N2O), potentially causing climate change.
How does sulfur dioxide from the atmosphere become available to ecosystems?
It becomes available when dissolved in precipitation as weak sulfuric acid or when it falls directly to Earth as fallout.
In nature, in what form does phosphorus exist?
As the phosphate ion (PO4^3-).
What is the process of water vapor turning into clouds?
Condensation.
What percentage of freshwater is bound as ice?
68.9%.
How is phosphate released into the soil, water, and air?
Volcanic activity and weathering of rocks.
What releases minerals from Earth's crust in the form of salts?
Weathering.
What is the reservoir for gaseous biogeochemical cycles?
Air or the oceans (via evaporation).
What is the role of denitrifying bacteria in the nitrogen cycle?
Converting nitrates into nitrogen gas, allowing it to re-enter the atmosphere.
How is phosphate returned to soil or water in the phosphorus cycle?
Through decomposition of biomass or excretion by consumers.
What are the two main forms in which carbon dioxide exists?
In the atmosphere and dissolved in water.
In which phase do other salts deposit out as sediment and rock in shallow seas?
Rock phase.
What is denitrification?
When bacteria converts nitrates into nitrogen gas, allowing it to re-enter the atmosphere.
Where does long-term storage of organic carbon occur?
When matter from living organisms is buried deep underground and becomes fossilized.
What brings stored carbon back into the carbon cycle?
Volcanic activity and human emissions.
What is the impact of acid rain on the man-made environment?
Chemical degradation of buildings.
What are most groundwater reservoirs known as?
Aquifers.
What kind of damage does acid rain cause?
Damage to aquatic ecosystems.
What is the result of excessive growth of algae caused by excess phosphorus and nitrogen?
Dead zones in major rivers.
How do humans harvest groundwater to increase water availability?
By digging wells.
Which chemical elements are recycled in ecosystems?
Water, carbon, nitrogen, hydrogen, oxygen, phosphorus, and sulfur.
What is the mineral constituent of bones and teeth?
Phosphorus.
What percentage of freshwater is groundwater?
30.8%.
What is the term for the flow of freshwater over land from rain or melting ice?
Surface runoff.
What is the major environmental concern associated with the use of fossil fuels?
Climate change.
What happens to the salts that are deposited as sediment and rock in shallow seas?
They eventually get weathered and recycled.
Why has the pursuit of drinkable water through desalination been ongoing throughout human history?
To obtain drinkable water from saline sources.
What are the four major ways in which sulfur is deposited on land?
What percentage of the atmosphere is comprised of nitrogen?
Approximately 78%.
What is the significance of carbon in organisms by mass?
It is the second most abundant element.
What happens to sulfur as rain falls through the atmosphere?
It is dissolved in the form of weak sulfuric acid (H2SO4).
How does eutrophication occur naturally over centuries?
As lakes age and are filled in with sediments.
What do biogeochemical cycles enable?
The transformation of matter from one form to another.
What do soil bacteria supply terrestrial food webs with?
Organic nitrogen.
How is phosphate incorporated into organic material in the phosphorus cycle?
Taken up by producers and incorporated into organic material.
Where is a negligible amount of water found?
In the atmosphere.
What is eutrophication?
The process where excessive nutrients in a body of water cause overgrowth of plants and algae, leading to oxygen depletion and harm to aquatic life.
What process cycles organic carbon back into carbon dioxide gas?
Respiration.
What process converts liquid water to water vapor by solar energy?
Evaporation.
What is groundwater?
A significant subsurface reservoir of fresh water.
What percentage of water in the biosphere is contained in the oceans?
97.5%.
What processes nitrogen and nitrogenous waste from animals back into gaseous nitrogen?
Soil bacteria.
What does the term 'biogeochemical' refer to?
The consideration of the biological, geological, and chemical aspects of each cycle.
What is the fate of elements needed by living things in ecosystems?
They are recycled repeatedly.
How does phosphate enter the oceans?
Through surface runoff, groundwater flow, and river flow.
What do bacteria convert ammonium into?
Nitrites (NO2-) and then nitrates (NO3-).
Why should eutrophication matter to people living near the ocean?
Because it can lead to unhealthy or dying fish and other wildlife due to oxygen depletion.
What is the method of increasing water availability by collecting and storing rainwater?
Storing rainwater.
What happens to elements as they pass through ecosystems?
They are not lost and are recycled repeatedly.
In which molecules is carbon present?
It is present in all organic molecules and some non-organic molecules like CO2.
What is the process by which certain bacteria can convert nitrogen into a usable form?
Nitrogen fixation.
What happens to water vapor over time?
It condenses into clouds as liquid or frozen droplets.
What are the three components involved in biogeochemical cycles?
Biotic components, Geological & abiotic components, Chemical cycles.
What has the increased demand for fossil fuels caused in the atmosphere?
A drastic increase in the amount of carbon dioxide.
What is a reservoir in the context of biogeochemical cycles?
A place where something is kept in store.
How can sound agricultural and waste management practices help in protecting marine resources?
By preventing excessive nutrient runoff and reducing the risk of eutrophication.
What percentage of the human body is water?
About 70 percent.
Where does groundwater exist?
In the pores between particles in dirt, sand, and gravel, or in the fissures in rocks.
When did the use of fossil fuels accelerate?
In the 1800s.
What do nutrient circuits involve?
Nutrient circuits involve both biotic (living) and abiotic (nonliving) components of ecosystems.
What does precipitation (rain, snow, hail) do in the water cycle?
It returns water to Earth's surface.
What happens to phosphate dissolved in ocean water?
It cycles into marine food webs.
How do plants and other producers use nitrogen-containing molecules?
To make organic molecules.
How do biogeochemical cycles link different components of the environment?
They link living organisms with living organisms, living organisms with the non-living organisms, and non-living organisms with non-living organisms.
On what is many organisms dependent due to its small percentage?
The remaining 2.5% freshwater.
What happens to the nitrogen that is used by plants and producers?
It becomes available to consumers.
