05: Biogeochemical Cycle

Question 1

____ flows through an ecosystem and is dissipated as heat, but ____ are recycled.

Answer 1

Energy, Chemical Elements

Question 2

The ways in which an element—or compound such as water—moves between its various living and nonliving forms and locations in the biosphere is called as ____

Answer 2

(A) Biogeochemical Cycle

Question 3

Biogeochemical cycles important to living organisms include (enumerate the cycles)

Answer 3

Water Cycle
Carbon Cycle
Nitrogen Cycle
Phosphorus Cycle
Sulfur Cycle

Question 4

This is the pathway by which a chemical substance cycles the biotic and the abiotic compartments of Earth.

Answer 4

A Biogeochemical Cycle

Question 5

The biotic compartment is the ____ and the abiotic compartments are the ____.

Answer 5

Biosphere
Atmosphere, Hydrosphere and Lithosphere.

Question 6

____ flows, but ____ is recycled.

Answer 6

Energy, Matter

Question 7

The six most common elements in organic molecules that take a variety of chemical forms.

Answer 7

Carbon
Nitrogen
Hydrogen
Oxygen
Phosphorus
Sulfur

Question 8

The set of places where water can be found as it cycles on Earth—is large and diverse.

Answer 8

The Hydrosphere

Question 9

This is present as a liquid on the Earth’s surface and underneath the ground, as ice in the polar ice caps and glaciers, and as a vapor in the atmosphere.

Answer 9

Water

Water makes up more than half of our bodies

Question 10

This is found in all organic macromolecules and is also a key component of fossil fuels.

Answer 10

Carbon

Question 11

This is needed for our DNA, RNA, Proteins and is critical to agriculture.

Answer 11

Nitrogen

Question 12

This is a key component DNA, and RNA and is one of the main ingredients. Along with Nitrogen is in artificial fertilizers used in agriculture.

Answer 12

Phosphorus

Question 13

This is key to protein structure and is released to the atmosphere by the burning of fossil fuels.

Answer 13

Sulfur

Question 14

In percentage, how much water is our body made of?

Answer 14

Over 70%

Question 15

Of the water on Earth, ____ is salt water. Of the remaining water, over ____ is in the form of underground water or ice. All told, less than ___ of fresh water is found in lakes, rivers, and other available surface forms.

Answer 15

97.5%
99% (3.465%)
1% (0.035%)

Question 16

This cycle is driven by the Sun’s energy. The sun warms the ocean surface and other surface water, causing liquid water to evaporate and ice to sublime—turn directly from a solid to a gas. These sun-driven processes move water into the atmosphere in the form of water vapor.

Answer 16

Water Cycle

Question 17

Over time, water vapor in the atmosphere condenses into clouds and eventually falls as ____, rain or snow. When precipitation reaches Earth’s surface, it has a few options: it may evaporate again, flow over the surface, or ____—sink down—into the ground.

Answer 17

Precipitation, Percolate

Question 18

In general, water moves along the surface as ___ only when the soil is saturated with water, when rain is falling very hard, or when the surface can’t absorb much water.

Answer 18

Runoff

Question 19

In this process, water enters through the roots, travels upwards through vascular tubes made out of dead cells, and evaporates through pores called stomata found in the leaves.

Answer 19

Transpiration

Question 20

This is water found in the pores between particles in sand and gravel or in the cracks in rocks, and it’s an important reservoir of freshwater.

Answer 20

Groundwater

Question 21

This flows slowly through pores and fissures and may eventually find its way to a stream or lake, where it can become part of the surface water again.

Answer 21

Shallow groundwater

Question 22

These are usually the source of drinking or
irrigation water drawn up through wells.

Answer 22

Groundwater Reservoirs (or Aquifers)

Question 23

This is an essential element in the bodies of living organisms. It is also economically important to modern humans, in the form of fossil fuels.

Answer 23

Carbon

Question 24

___ from the atmosphere is taken up by photosynthetic organisms and used to make organic molecules, which travel through food chains. In the end, the carbon atoms are released as ____ in respiration.

Answer 24

Carbon Dioxide (CO2)

Question 25

The carbon cycle is most easily studied as two interconnected sub cycles: One dealing with ____ among living organisms One dealing with ____ through geologic processes.

Answer 25

Rapid Carbon Exchange
Long-Term Cycling of Carbon

Question 26

To release the energy stored in carbon-containing molecules, such as sugars, autotrophs and heterotrophs break these molecules down in a process called ____.

Answer 26

Cellular Respiration

Question 27

In this process, the carbons of the molecule are released as carbon dioxide.

Answer 27

Cellular Respiration

Question 28

These organisms also release organic compounds and carbon dioxide when they break down dead organisms and waste products.

Answer 28

Decomposers

Question 29

This is a key component of the bodies of living organisms. These atoms are found in all proteins and DNA.

Answer 29

Nitrogen

Question 30

Nitrogen exists in the atmosphere as __ gas.

Answer 30

N2 (Dinitrogen)

Question 31

In this process, bacteria convert N2 into ammonia, a form of nitrogen usable by plants. When animals eat the plants, they acquire usable nitrogen compounds.

Answer 31

Nitrogen Fixation

Question 32

This is the nutrient that’s in shortest supply and limits growth.

Answer 32

Limiting Nutrientnm

Nitrogen is a common limiting nutrient in nature, and agriculture.

Question 33

When fertilizers containing nitrogen and phosphorus are carried in runoff to lakes and rivers, they can result in blooms of algae—this is called ___.

Answer 33

Eutrophication

Question 34

In percentage, how much nitrogen is the Earth’s atmosphere made of?

Answer 34

78%

Question 35

When a nutrient is limiting, adding more of it will ____ growth.

Answer 35

Increase

Question 36

This is an essential nutrient found in the macromolecules of humans and other organisms, including DNA.

Answer 36

Phosphorus

Question 37

Most phosphorus in nature exists in the form of ____.

Answer 37

Phosphate Ion (PO4)3

Question 38

This is often the limiting nutrient, or nutrient that is most scarce and thus limits growth, in aquatic ecosystems.

Answer 38

Phosphorus

Question 39

When nitrogen and phosphorus from fertilizer are carried in runoff to lakes and oceans, they can cause ____, the overgrowth of algae. The algae may deplete oxygen from the water and create a ____.

Answer 39

Eutrophication, Dead Zone

Question 40

This is released by the weathering of rocks.

Answer 40

Sulphur

Question 41

Sulphur comes in contact with air and is converted into ____.

Answer 41

Sulphates

Question 42

Sulphates are taken up by plants and microbes and are converted into
____.

The ____ of Sulphur is then consumed by the animals through their food and thus Sulphur moves in the food chain.

Answer 42

Organic Form

Question 43

When the animals die, some of the Sulphur is released by ____ while some enter the tissues of microbes.

Answer 43

Decomposition

Question 44

There are several natural sources such as ___, that release Sulphur directly into the atmosphere.

Answer 44

Volcanic Eruptions
Evaporation of Water
Breakdown of Organic Matter in Swamps

Question 45

This Sulphur falls on earth with ____.

Answer 45

Rainfall