Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Ecology > Exam Four: Learning Objectives > Flashcards

Exam Four: Learning Objectives Flashcards

1
Q

What is a tropic cascade?

A

An effect of a predator that extends beyond one link in a food web

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

Why would a shallow marine ecosystem become a kelp forest or an urchin barren?

A

Kelp are eaten by urchin, which are eaten by otters
Fish are eaten by seals which are eaten by orcas
If commercial fisheries take out fish, seals die off, orcas are forced to eat otters, which increased sea urchin, decreasing kelp forest

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

Why is apparent competition considered an indirect interaction?

A

Consider two species on the same trophic level, when species A is present, population density of species B declines because species A attracts predators and they consume both A and B

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

When would two species exhibit apparent competition?

A

they should share predators/ consumers
mustard and bunchgrass

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

T/F: There is a difference between apparent competition and competition for resources

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Identify two species with the potential to exhibit resource competition?

A

they should share a resource

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How do fish enclosure and exclosure experiments in streams demonstrate trophic cascades?

A

Largemouth bass indirectly benefited zooplankton and indirectly reduced algae density due to their direct interaction (consumption) of minnows

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

Define feeding guild

A

A group of species exploiting a common resource base in a similar fashion

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

What is an example of a feeding guild

A

Filter feeders, insectivores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Define a keystone species

A

low abundance, but big impact because they play a special role

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

Define a foundation species

A

define the ecosystem; abundant, provide structure, habitat, and mutualistic support to most other species; regulate flows of energy, nutrients, water (mangrove trees in a mangrove forest, coral in a coral reef)

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

Identify ecological impacts of starfish, as keystone predators

A

predatory sea stars were removed, which resulted in the loss of species and a decline in species richness

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

Identify the ecological impacts of cleaner wrasses and some native ant species, as keystone mutualists

A

removal of cleaner wrasse resulted in a decline in fish species richness, addition of cleaner wrasse to coral reefs increased fish species richness; exclusion of seed dispersing ants decreases recruitment of large-seeded plants

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

Why will predation increase in diversity in a community if the main prey species are strong competitiors?

A

Snails were added to this tide pool and the tasty algae population declined, snails were removed and the tasty algae increased while the crusty algae population declined

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

Define a trophic level

A

each feeding level in a food chain

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

Define a food web

A

shows feeding relationships in a community; can be used to document main energy flows or aggregate species into groups

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

T/F: Snail density increases will increase algae species richness

A

True - up to a point, at very high densities, herbivory is so intense algae diversity declines

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

How does energy flow food webs?

A

Sunlight to primary producers to herbivores and detritus
deritius goes to detrivores and eat dead predators/ carnivores
herbivores go to predators/ carnivores
Heat is lost in each step

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

Define a primary producer

A

photosynthesizers (plants, algea); chemoautotrophs and their detritus

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

Define an autotroph

A

aka primary producers
synthesize organic molecules from inorganic carbon (CO2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Define primary production

A

production of new organic matter, or biomass, by autotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Define a heterotroph

A

aka consumers, secondary producers
consume organic matter synthesized by other organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Photosynthesis transforms __ energy into sugars (__ __) that provide energy to the rest of the food web. Autotrophic chemosynthesis transforms __ energy of reduced mineral compounds into organic __

A

solar; organic matter
potential; energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the equation for respiration?

A

6O2 + C6H12O6 –(ATP)-> 6CO2 + 6H2O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Breakdown (__) of sugar molecules drives production of usable cellular __ (__), releasing __ in the process. Both _- and __ perform respiration

A

catabolism; energy; ATP; CO2
photoautotrophs, heterotrophs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Define respiration

A

converts energy stored in sugar into ATP; reverse of primary production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Write the equation for primary production, balancing both __ and __

A

matter; energy
6CO2 + 6 H2O –(solar energy)–> C6H12O6 + 6O2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Define GPP

A

gross primary production
all the carbon fixed by autotrophs (primary producers) in an ecosystem; all of the photosynthesis (and chemoautotrophy) occuring in an ecosystem

29
Q

Define NPP

A

Net primary production
organic carbon remaining after autotrophs meet their own energy needs (after accounting for primary-producer respiration, Rp); energy and biomass available for plants to add biomass and to supply food and energy for the rest of the food web
GPP - Rp = NPP

30
Q

If an ecosystem is adding biomass, GPP _ Re, so NEP is __

A

> ,positive

31
Q

Define Rp, Rh, and Re

A

Rp - respiration done by plants
Rh - respiration by all heterotrophs
Re - respiration of everyone (Re = Rh + Rp)

32
Q

Define NEP

A

Net ecosystem production
organic matter left after all organisms have met energy needs
NPP - Rh = NEP

33
Q

What percentage of GPP is allocated to Rp, and what percentage is left over for NPP?

A

Rp consumes about half of the GPP generated by plants
NPP is approx. half of GPP

34
Q

GPP is partitioned into __ and __?

A

Rp and NPP

35
Q

Describe evidence showing the influence of climate on primary production

A

productivity is greater in wetter and warmer biomes
grassland productivity is influenced by precipitation, more precip = more NPP

36
Q

Describe evidence of the influence of plant growth form (leaf area) on primary production

A

Productivity is greater where there is more leaf area

37
Q

Define the term limiting nutrient

A

nutrient that is least available relative to demand; nutrient is in limited supply

38
Q

Describe research evidence you would use to identify which nutrient is limiting

A

addition of a limiting nutrient increases productivity

39
Q

Identify the nutrient that typically limits primary production in various types of in various types of aquatic ecosystems

A

lakes - phosphorus
streams, rivers, estuaries, and oceans - Nitrogen

40
Q

Sketch a 2x2 factorial design in which N and P fertilizers are experimentally added to ecosystems

A

Ambient N - Ambient P and +P
+N - Ambient P and +P

41
Q

Describe the effect of moderate grazing on plant productivity, and explain why this effect happens in reference to compensatory growth

A

Compensatory growth: greater primary production at moderate grazing
moderate grazing results in lower plant respiration, lower water loss, and less shading, thereby promoting a faster rate of leaf growth

42
Q

Provide evidence which demonstrates that species richness of the primary producers (plants, algae) influences primary production, and explain why this effect occurs

A

trophic cascades, high zooplankton density results in low algae growth (and vice versa)

43
Q

Define ecologyical efficiency

A

the percent of energy in biomass at one trophic level that is transferred to biomass at the next level

44
Q

Why is ecological efficiency only about 5-20%?

A

limited consumption, poor assimilation, respiration and heat

45
Q

Define secondary production

A

production of biomass by heterotrophic consumer organisms

46
Q

Describe evidence from research demonstrating bottom-up control of secondary production

A

If precipitation influences primary production, and if primary production regulates secondary production, does precipitation influence secondary productions???

YES - secondary production in savannah ecosystems is higher where there is more precipitation; precipitation fosters more primary production, which enriches secondary production

47
Q

Explain how the roles of the atmosphere and sedimentary rock are different in the global cycle of phosphorus than in the global cycles of nitrogen and carbon

A
48
Q

Identify the biggest human impacts on the global cycles of phosphorus, nitrogen, and carbon

A
49
Q

Identify the roles of nitrogen fixation and denitrification in the exchange of nitrogen to and from the atmosphere

A
50
Q

Describe the role oceans play in the global carbon cycle

A
51
Q

Identify the sources of nutrient input to ecosystems, and the mechanisms for nutrient export from ecosystems

A
52
Q

Create a graphic ‘box-and-arrow’ model of an ecosystems nutrient budget, showing ecosystem boundaries, reservoirs or pools within the ecosystem, fluxes in and out of the ecosystem, and fluxes among reservoirs within the ecosystem

A
53
Q

Create a box and arrow model depicting an ecosystem with positive nutrient retention and one that shows net nutrient loss by the ecosystem

A

input and output fluxes should be different sizes

54
Q

How are decomposition and mineralization related and separate?

A
55
Q

__ is a process that occurs during __

A

mineralization; decomposition

56
Q

Define organic nitrogen and organic phosphorus

A
57
Q

Identify inorganic (__) chemical compounds that carbon, nitrogen, and phosphorus are transformed into when they are mineralized

A

mineral
!!

58
Q

Describe how rates of decomposition are affected by temperature, soil moisture, litter tissue properties, and nutrient supply

A
59
Q

Explain how the invasion of certain areas in Hawaii by Myrica faya has altered nitrogen cycling in those locations

A
60
Q

Explain how grazing of vegetation can accelerate nutrient cycling

A
61
Q

Describe how pocket gophers influence the spatial heterogeneity of soil nitrogen and light across a grassland landscape

A
62
Q

Explain the concept of nutrient spiraling, and identify the type of ecosystem in which nutrient spiraling is a particualry useful concept

A
63
Q

Define spiraling length

A
64
Q

What factors result in longer nutrient spiraling lengths

A
65
Q

Identify how nitrogen storage in organism tissues, and rapid cycling of nitrogen among organisms and detritus, help to shorten spiraling lengths and improve nitrogen retention in streams

A
66
Q

Explain how nitrogen isotopes were used to discover the role of salmon migration in transporting marine-derived nitrogen to inland streams and riparian forests

A
67
Q

Describe the typical effect of disturbance on an ecosystem;s nutrient budget. Support your description with evidence about nitrogen export from forested watersheds and phosphorus export from stream sediments

A
68
Q

Provide evidence from watershed studies demonstrating that human activities tend to accelerate nutrient cycling

A

Ecology (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions