Biochemical Cycles Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What are Biochemical Cycles?

A
  • Include biological organisms & geological processes= includes processes that occur on many spatial scales from cellular to planetary
  • Arise from a fixed number of atoms of each type of element
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Carbon is the major…

A

Constituent of the bodies of organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is carbon the major constituent of the bodies of organisms?

A
  • BC carbon atoms help form the framework of all organic compounds
  • Almost 20% of weight of human body is carbon
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the most significant carbon-containing compound?

A
  • CO2
  • It makes up .03% of the volume of the atmosphere
  • And it reacts spontaneously with water to form bicarbonate ions (HCO3-)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are Biogeochemical cycles?

A
  • Emphasize that the cycles of chemical elements involve biological processes & organisms, & geological (abiotic) systems & processes
  • They cross the boundaries of ecosystems
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What do Biogeochemical cycles include?

A
  • Include processes that occur on many spatial scales from cellular to planetary
  • They also include processes that occur on multiple time scales= biochemical reactions (secs) to the weathering of rocks (millennia)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the most significant carbon-containing compound in abiotic environments of organisms?

A

-Carbon dioxide= makes up .03% of the volume of the atmosphere= 750 billion metric tons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How does CO2 react with water?

A

-It reacts spontaneously w/ water to form bicarbonate ions= HCO3-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How is the carbon cycle like in terrestrial ecosystems?

A
  • Plants & other photosynthetic organisms take in CO2 from the atmosphere & use it in photosynthesis to synthesize the carbon-containing organic compounds
  • This is sometimes called carbon fixation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What does Fixation refer to?

A

-The metabolic reactions that make nongaseous compounds from gaseous ones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How do photosynthetic plants & animals obtain energy?

A

-They both break down some of the organic compounds available to them via aerobic cellular respiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How is the carbon cycle in aquatic ecosystems?

A
  • It is similar to the process for terrestrial ecosystems

- BUT inorganic carbon is present in the water has CO2 & HCO3- ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does CO2 & HCO3- have in common?

A
  • They both are present in the water of aquatic ecosystems

- They both act as sources of carbon for photosynthesis by algae & aquatic plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What kind of microbes provide an additional dimension to the global carbon cycle?

A

-Microbes that break down organic compounds by anaerobic cellular respiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are Methanogens?

A

-They are microbes that produce methane CH4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a major source for Methane?

A

-Wetland ecosystems bc methogens live in oxygen free sediments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens to Methane when it enters the atmosphere?

A
  • It is oxidized abiotically to CO2

- BUT the CH4 that remains isolated from oxygen can last for a lot of time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the 2 dimensions of the global carbon cycle?

A
  • Microbes that break down organic compounds

- And that some parts of the cycle may proceed faster than others

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What effect would different parts of the global carbon cycle proceeding faster than other parts?

A

-There will be an imbalance of the cycle which can cause burned fossil fuels to rapidly return to the atmosphere= higher concentration of CO2 levels= global warming

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the 2 green house gases?

A
  • Methane

- Carbon dioxide

21
Q

What is the distinctive feature of the Water cycle?

A

-It is that since water is a compound, it can be synthesized & broken down

22
Q

How is water synthesized in the water cycle?

A

-It is synthesized during aerobic cellular respiration

23
Q

How is water split in the water cycle?

A

-It is chemically split during photsynthesis

24
Q

What is the relationship between water synthesizing & splitting in the water cycle?

A

-The rates are equal= constant amount of water cycles throughout the biosphere

25
Q

What a key part of the water cycle?

A

-The liquid from the earth’s surface evaporates into the atmosphere

26
Q

Why does evaporation occur faster when there’s more solar radiation on the earth’s surface?

A

-Bc the change of water states from liquid to gas requires a lot of thermal energy

27
Q

How does evaporation occur?

A
  • It occurs directly from the surfaces of bodies of water
  • BUT 90% of the water passes through plants, trees, grasses & then that water leaves from their leaves & other surfaces
28
Q

what is Transpiration?

A

-The process of water evaporating through the plant’s leaves or other surfaces before it reaches the atomosphere

29
Q

How does evaporated water exist in the atmosphere?

A

-As a gas

30
Q

What causes the formation of clouds?

A
  • The condensation of gaseous water (water vapor) into droplets or crystals
  • If these droplets/ crystals are big enough they’ll fall to the surface of the earth as precipitation (rain/snow)
31
Q

What is Groundwater?

A
  • The water underground the bodies of water (NOT surface water)
  • It is the most important reservoir of water on land= representing over 95% of freshwater in the U.S
  • It consists of 2 subparts
32
Q

How does Groundwater occur?

A

-It occurs via Aquafiers

33
Q

What are Aquafiers of Groundwater?

A
  • They are permeable underground layer of rock, sand, & gravel that are often saturated with water
  • BUT water flows through here MUCH slower than surface water (few mm to a meter per day)
34
Q

What are the 2 subparts of Groundwater?

A
  • The upper layer= water table

- The lower layer= confined layers of groundwater

35
Q

What is the Upper layer of groundwater?

A
  • It constitutes the “water table”

- It is unconfined in a sense that it flows into streams & is partly accessible to roots of plants

36
Q

What is the Lower layer of groundwater?

A
  • It is confined layers of groundwaters

- These layers are out of reach to streams & plants but can be tapped by wells

37
Q

How is groundwater recharged?

A

-It is recharged by water that percolates downward from above= precipitation

38
Q

What is nitrogen a component of?

A
  • All proteins & nucleic acids

- It is also the chemical element that is the SHORTEST in supply relative to the needs of organisms

39
Q

Why is nitrogen the shortest supply since the atmosphere is so rich with is?

A

-It is bc nitrogen is in chemical form (N2) so plants & organisms have no way to use nitrogen in its chemical form

40
Q

What is the source of nitrogen for animals?

A

-The major source are nitrogen-containing organic compounds synthesized by plants, algae, & other microbes

41
Q

What is the source of nitrogen for plants & algae?

A

-The 2 most common sources= NH3 & NO3- (nitrate ions)

42
Q

What how is Nitrogen balanced within plants & algae?

A
  • Certain prokaryotic microbes can synthesize ammonia & nitrate from N2 in the atmosphere= makes atmospheric oxygen accessible for plants & algae
  • While other prokaryotes turn NH3 & NO3- into N2= making the nitrogen inaccessable
43
Q

What is Nitrogen Fixation?

A
  • The synthesis of nitrogen containing compounds from N2

- SPECIFICALLY the synthesis of NH3 to N2

44
Q

What is the steps of Nitrogen Fixation?

A
  • The synthesis of NH3 from NH2

- then other prokaryotic microbes oxidize part of it to form NO3-= nitrification

45
Q

What is the nitrogen base complex?

A

-They are enzymes that allow certain prokaryotes to accomplish nitrogen fixation

46
Q

What is Dentrification?

A

-The ability that other prokaryotes have to convert the nitrogen in NO3- into N2 or other nitrogenous gases like N2O)

47
Q

What is the form of waste that Nitrogen can take?

A
  • Most animals excreting nitrogen from proteins like NH3
  • While humans & other mammals excrete nitrogen as Urea in their urine
  • Many microbes convert the urea to NH3
48
Q

What is the Phosphorus cycle?

A

-Phosphorus only occurs in the liquid & solid states= DOES NOT enter the atmosphere