Important Cycles to know for APES

Question 1

Where is sulfur sourced from?

Answer 1

Sulfur is most commonly sourced from rocks and decomposing organisms within the Earth.

Question 2

Where do we find these sources?

Answer 2

These sources are commonly found within geographical sinks, Earth’s soil, and Bodies of Water. It is also commonly sourced by producers.
It exists in rocks and is released through soils and waters. Producers absorb it through their roots.
Volcanic eruptions make sulfur dioxide, burning of fossil fuels, and mining metals

Question 3

What are the human impacts of sulfur?

Answer 3

Humans burning fossil fuels can release sulfur, which can cause sulfuric acid and acid rain

Question 4

Why is the sulfur cycle important?

Answer 4

The movement of sulfur around the biosphere allows for organisms to use oxygen.

Question 5

Why is the water cycle important?

Answer 5

Allows essential molecules to move within and between cells, draws nutrients into the leaves of trees, and dissolves and removes toxic materials

Question 6

What is water?

Answer 6

Primary agent responsible for dissolving and transporting chemical elements

Question 7

What is the hydrological cycle?

Answer 7

The movement of water throughout the biosphere

Question 8

The first step of the hydrological cycle

Answer 8

Heat from the sun leads to the evaporation of water
Transpiration occurs from plant leaves and leads to water evaporating

Question 9

The 2nd step of the hydrological cycle

Answer 9

The water vapor that rises from evaporation cools to make clouds (condensation)

Question 10

The 3rd step of the hydrological cycle

Answer 10

Precipitation occurs from the clouds, and this water is returned to the Earth. The water can be absorbed by soil and become groundwater, and runoff water goes into the oceans, lakes, and streams, and the cycle begins again

Question 11

What is carbon?

Answer 11

Long chains of organic molecules that form membranes, walls, backbones of protein, and store energy

Question 12

Why is carbon (and the carbon cycle) important?

Answer 12

It is the most important element to living organisms (20% of the body), and is needed to support many life systems on the planet

Question 13

The movement of carbon around the biosphere

Answer 13

Can occur in biotic and abiotic organisms. Is very fast in living and biotic organisms, but can be slow on abiotic or dead organisms (like rocks and dead animals)

Question 14

The importance of the carbon cycle to Photosynthesis and Respiration

Answer 14

Photosynthesis: take in co2 and incorporate into tissues
Returned to co2 when they respire
Returned after organisms die
Decomposers break down dead
Returns co2 to water/air with respiration

Question 15

Exchange and sedimentation with the carbon cycle

Answer 15

Exchange of carbon between atmosphere and ocean
Photosynthesis of algae (releases carbon)
Co2 dissolved in ocean combines with calcium ions to form calcium carbonate which makes limestone through sedimentation
Accumulates a lot over the years, creating a large supply of carbon

Question 16

Burial & The Carbon Cycle

Answer 16

Dead biomass pool is buried and incorporated into ocean sediment
Becomes fossilized over time
These become our fossil fuels
Rougly equal input and output (steady)
Carbon is being output of the earth from this pool of fossil fuels, but is put back on as emissions- this is not good for the ozone layer

Question 17

Extraction and Combustion with the Carbon Cycle

Answer 17

Reliance on coal and oil as natural energy sources -> carbon extraction
Extraction doesn’t alter cycle
Combustion: releases into the atmosphere
Combustion, respiration, and decomposition all release carbon into the atmosphere as co2 or into soil as ash
Can be bad for the environment!

Question 18

Human impacts of the Carbon Cycle (especially manmade)

Answer 18

Absence of humans is a steady state
Taken in by photosynthesis = released by decomposition
Buried in fossil fuel pools = released slowly
Industrial revolution is the turning point in leading to the combustion of fossil fuels, which leads to excess co2 and increasing heat in the biosphere
Tree harvesting- cutting and burning hurts the environment
Increased absorption of the ocean
This can lead to negative human health impacts and environmental health impacts and cause decreases in biodiversity and lifespans

Question 19

What is nitrogen?

Answer 19

A limiting nutrient that forms acids, builds proteins, nucleic acids, building blocks of dna and rna. Is like 78% of the atmosphere

Question 20

Why is nitrogen and the nitrogen cycle important?

Answer 20

Nitrogen is needed in high amounts, as it is a limiting nutrient that makes acids, builds proteins, nucleic acids, and is the building blocks of DNA and RNA and is a high composition of the atmosphere. It allows for many chemical transformations and is essential for thriving human life and plant life in healthy amounts.

Question 21

Nitrogen Fixation (Nitrogen Cycle, Step 1)

Answer 21

The Process by which some organisms can convert nitrogen gas molecules directly into ammonia
Converting nitrogen gas into nitrogen producers can use
Can be Biotic or abiotic
N2 -> nh3 -> nh4
Cyanobacteria and bacteria in legumes can do this
Excrete excess ammonium ions into the plants root system -> supplies the bacteria with sugar for photosynthesis
Abiotic:
Lightning, combustion converts no2 to no3 (nitrate) which goes into the earth via precipitation
Humans found a way to do it much quicker- can be beneficial and detrimental

Question 22

Nitrification (Nitrogen Cycle, Step 2)

Answer 22

The Conversion of ammonia into nitrite and then nitrate
Nh4 -> no2 -> no3
Conducted by specialized species of bacteria

Question 23

Assimilation (Nitrogen Cycle, Step 3)

Answer 23

Process by which producers incorporate elements into their tissue
Consumers feed and producers nitrogen is assimilated into the tissue of consumer and the rest is eliminated as waste

Question 24

Mineralization (Nitrogen Cycle, Step 4)

Answer 24

Process by which fungal and bacterial decomposers break down the organic matter found in dead bodies and waste products and convert it into inorganic compounds
Can be called ammonification because organic molecules are converted into inorganic ammonia (taken by producers and nitrification)

Question 25

Denitrification (Nitrogen Cycle, Step 5)

Answer 25

Conversion of nitrate in a series of steps into the gasses nitrous oxide and eventually nitrogen gas which is emitted into the atmosphere
The Final step in the cycle
Specialized bacteria that live under anaerobic conditions perform it

Question 26

The Impacts of the Nitrogen Cycle

Answer 26

Can have detrimental effects- adding nitrogen to a plot reduces number of species by 48%
In ecosystems containing species that have adapted to the environment over thousands of years, changing conditions is likely to cause changes in biodiversity and movement of energy through the cycling of matter in an ecosystem

Question 27

What is phosphorous?

Answer 27

An essential element to living organisms by forming bones and teeth, as well as DNA and RNA. It is not present in the atmosphere (or, shouldn’t be) and is a limiting nutrient that can be lethal in huge quantities

Question 28

Where is phosphorous sourced from?

Answer 28

Phosphorous is sourced from rocks, decomposing organisms, sinks, Earth’s soil, and producers

Question 29

How does the phosphorous cycle occur?

Answer 29

The phosphorous cycle occurs on land and water, and has no gas phase. It rarely changes form and stays in phosphate (PO4)^3- form

Question 30

Assimilation and Mineralization (Phosphorous Cycle, Stage 1)

Answer 30

Producers take up inorganic phosphate and assimilate it into their tissues as organic phosphate
The producers die -> decompose -> mineralize into inorganic phosphate

Question 31

Sedimentation, Geological Uplift, and Sedimentation (Phosphorous Cycle, Stage 2)

Answer 31

Phosphorous is not very soluble
Precipitates out as phosphate-laden sediments in ocean
Geologic forces lift ocean layers making mountains
Rocks in mountains are weathered
Phosphorous goes to land and water
Phosphorous is held tightly by soil (not easily leached)
Little of it is available in bodies of water

Question 32

The Human Impacts of the Phosphorous Cycle

Answer 32

Dramatic effects
Humans are mining it to make fertilizer
Excess can be leached out of water (bodies of water have very little of it anyway)
Adding phosphorous can greatly increase growth of producers
Rapid increase in algal population means more algal bloom
Household detergents containing phosphates got into the water leading to a ban on phosphates in cleaning products
Too much can decrease levels of dissolved oxygen- can cause fish kills