"our Global Environment" Chapter 1

Front 1

What is a biosphere?

Back 1

The portion of Earth where life occurs.

Front 2

In what regions are the greatest number of living things found?

Back 2

The permanent snow line of tropical/subtropical mountain ranges (about 20,000 ft) to the limit of light penetration in the oceans (about 600 ft deep).

Front 3

When were the first living organisms on Earth?

Back 3

About 3.5 billion years ago.

Front 4

What made possible the emergence of higher forms of life?

Back 4

The creation of the modern atmosphere.

Front 5

Describe how species interact in the biosphere?

Back 5

Species interact both with each other & with their physical environment. Over long periods of time they become modified in response to environmental pressures, and, in turn, they themselves modify their physical surroundings.

Front 6

What is one constant feature of evolutionary progression?

Back 6

The ability of living things to modify their surroundings and the tendency of other organisms to respond positively or negatively to such changes.

Front 7

Define ecosystem and what the concept reflects?

Back 7

Nature can be divided into basic functional units called ecosystems.

Hint 7

This reflects the recognition of the complex manner in which living organisms interact with each other and with abiotic components of their environment to process energy & cycle nutrients. It emphasizes the interdependence of the biotic & abiotic components of an area.

Front 8

What are abiotic components?

Back 8

Nonliving components.

Front 9

What is a biotic community?

Back 9

A natural grouping of different kinds of plants & animals within any given habitat.

Front 10

What is a population?

Back 10

Individuals of the same species living together within a given area.

Front 11

Why is the concept of community important to ecological principles?

Back 11

It emphasizes the fact that different organisms dwell together in an orderly manner, and the concept can be used by humans to manage a particular organism, in the sense of increasing or decreasing its numbers.

Hint 11

(pg 9)

Front 12

Name something that can be as destabilizing to an established biotic community as removing a component species?

Back 12

Introducing a nonnative species.

Hint 12

(pg 10)

Front 13

What are ecological dominants, and what are some of their features?

Back 13

Organisms which exert a major modifying influence on the community.

Hint 13

-Ecological dominants are generally those species that control the flow of energy through the community.
-The number of dominant species within a community becomes progressively fewer as one moves toward the poles and greater the closer the community is to the tropics.
-The number of dominant species are fewer in regions where climatic conditions are extreme.
(pgs 11-13)

Front 14

Where and why are plants sometimes the dominant species?

Back 14

Plants are dominant in most terrestrial biotic communities.

Hint 14

Plants are dominant because they not only provide food & shelter for other organisms, but also directly affect and modify their physical environment.
(pg 12)

Front 15

What is the role of keystone predators?

Back 15

They moderate competition among the species upon which they prey.

Hint 15

(pg 13)

Front 16

What are biomes and what are some features of them?

Back 16

General groupings that are recognized by the distinctive life forms of their dominant species.

Hint 16

-Each biome has its own pattern of rainfall, seasons, maximum & minimum temperatures, and changes of day length.
-The earth's biomes form continuous latitudinal bands are the globe.
(pg 13)

Front 17

What is usually the key characteristic of a biome?

Back 17

The dominant type of vegetation.

Hint 17

(pg 13)

Front 18

What are some features of the tundra biome?

Back 18

-Tundra is on the northernmost of the world's land masses.
-It is characterized by permafrost (permanently frozen subsoil).
-Rainfall is low and it is windy.
-There are few trees.
-Animal life is limited in the umber of species but very abundant in the number of individuals.
-Very fragile environment because of the slow rates for growth & decomposition of plants.

Hint 18

(pg 13)

Front 19

What are examples of the dominant vegetation & animals in tundras?

Back 19

Moss, lichens, grass, and small perennials.

Hint 19

-Caribou, reindeer, birds, insects, polar bears, lemmings, foxes, rabbits, and fish.
-Reptiles & amphibians are absent.

Front 20

What are some features of the taiga (borreal forest) biome?

Back 20

-The dominant vegetation is conifer trees, with some deciduous trees that are much less diverse in species.
-Precipitation is moderate.
-Due to poor drainage there are lots of lakes, ponds, and bogs.
-Populations undergo "boom or bust" cycles fairly regularly due to the lack of diversity of species.

Hint 20

(pg 14)

Front 21

What are some features of the temperate deciduous forest biome?

Back 21

-South of the taiga.
-Climate is milder and rainfall is abundant.
-Soil types & elevations vary widely.
-Great variety of animals.
-Soils are rich in nutrients due to annual leaf drop.

Hint 21

(pg 14)

Front 22

What are some features of the grasslands biome?

Back 22

-Annual rainfall is not sufficient to sustain the growth of trees.
-Evaporation rates are high.
-Grasses, herds of grazing animals, carnivores, and rodents are dominant.

Hint 22

(pgs 14-15)

Front 23

What are some features of the desert biome?

Back 23

-Less than 10 inches of rainfall per year.
-High daytime temperatures and cold nighttime temperatures.
-Animals that are active at night.
-Very fragile environment.

Hint 23

(pg 15)

Front 24

What are some features of the tropical rain forest biome?

Back 24

-Found in Central/South American, central Africa, and South/Southeast Asia.
-High temperatures & high rainfall (100 inches+).
-Year-round temperature variation is slight.
-A great diversity of plant & animal species.
-Have four layers of plant growth (top canopy, lower canopy, understory, and ground level).
-Numbers of individuals of a particular species are usually limited.

Hint 24

(pg 15)

Front 25

What is a niche?

Back 25

A position unique to each species in any biotic community, determined mostly by its size and food habits.

Hint 25

(pg 16)

Front 26

What is the Principle of Competitive Exclusion?

Back 26

When two species are competing for the same limited resources, only one will survive.

Hint 26

(pg 16)

Front 27

What does niche diversification illustrate?

Back 27

Throughout evolutionary history, ecosystems have become exceedingly complex through increasingly effective adaptation of organisms within any natural community.

Hint 27

(pg 18)

Front 28

What are limiting factors, and what are usually limiting factors?

Back 28

Environmental conditions that limit or control where an organism can live.

Hint 28

-Components that are relatively constant in amount and moderately abundant are seldom limiting factors, especially if the individual has a wide limit of tolerance (for ex: oxygen).
-If an indivdual has a narrow limit of tolerance for a factor that exists in low or variable amounts, then that factor might be a limiting factor (ex: lack of oxygen).
(pg 19)

Front 29

Explain the Law of the Minimum?

Back 29

-Developed by Justus Liebig
-The growth of a plan is dependent on the amount of foodstuff which is presented to it in a minimum quantity.
-Has been expanded to include light, temperature, pH, water, oxygen supply, and soil types as possible limiting factors.

Hint 29

-When some factor other than the minimum one is available in very high concentration, it may moderate the rate at which the critical one is used.
(pg 19)

Front 30

What is an organism's limits of tolerance?

Back 30

The range in between the organism's ecological minimum & maximum.

Hint 30

(pg 20)

Front 31

When are factors most likely to be limiting?

Back 31

During the reproductive period.

Hint 31

(pg 20)

Front 32

What is the ultimate source of all life activities?

Back 32

The sun

Hint 32

(pg 21)

Front 33

What is the First Law of Thermodynamics?

Back 33

Energy can neither be created nor destroyed, even though it may be changed from one form into another.

Hint 33

It's also called the Law of Conservation of Energy
(pg 21)

Front 34

What is the Second Law of Thermodynamics?

Back 34

With every energy transformation, there is a loss of usable energy.

Hint 34

Note that it's the availability, not the total amount of energy, that is what decreases. This law implies that energy moves in a unidirectional way though ecosystems, becoming ever more dispersed & eventually is degraded to heat.
(pg 22)

Front 35

Describe the concept of food chains?

Back 35

It conveys a general understanding of how energy moves through ecosystems.

Hint 35

(pg 22)

Front 36

What are the 3 broad categories that living components in an ecosystem can be subdivided into, and give some examples?

Back 36

-Producers.
-Consumers.
-Decomposers.

Hint 36

-The green plants that convert the sun's energy into food energy.
-Animals.
-Primarily bacteria and fungi, some insects.
(pg 22)

Front 37

What are the 3 types of food chains, and give some examples.

Back 37

-A grazing food chain (or a predator chain).
-The detritus food chain.
-Parasitic chains

Hint 37

-Grass-->rabbit-->fox
-Dead organic mater broken down by microorganisms-->small animals-->larger animals
-Dogs-->fleas-->parasitic protozoans
(pgs 22-23)

Front 38

What is a trophic level? How many can there be?

Back 38

A stage in a food chain.

Hint 38

-They are limited to 4-5 trophic levels due to energy considerations.
-Note that individuals of the same species may feed at different trophic level, depending on factors such as age or sex.
(pgs 23, 27)

Front 39

What is the purpose of ecological pyramids?

Back 39

To describe the relationship among members of various trophic levels.

Hint 39

(pg 23)

Front 40

Describe the look of ecological pyramids? Shape? Who is on each level?

Back 40

-The bottom of the pyramid is energy-producing plants (usually the smallest, but very abundant).
-Then a smaller number of herbivores that feed upon them.
-Then a smaller number of primary carnivores.
-Then a smaller number of secondary carnivores, which are usually the largest in the community.

Hint 40

(pg 23)

Front 41

What is biomass and at what trophic level is it usually the greatest?

Back 41

The living weight of organisms (measured as dry weight per unit area), which is in indicator of the amount of energy stored within an ecosystem.

Hint 41

It's greatest at the producer trophic level.
(pg 23)

Front 42

What is ecotourism?

Back 42

Responsible travel to natural areas that conserves the environment and sustains the well-being of local people. It requires that the impact of travel on the environment & people of the host country be a positive one.

Hint 42

Note that it's the fastest-growing segment of the travel & tourism industry since the mid-1990s.
(pg 24)

Front 43

Describe "food web."

Back 43

May be a better concept than a food "chain" because many organisms (especially top level consumers) feed on many different species, and on more than one trophic level.

Hint 43

(pg 27)

Front 44

What is biogeochemical cycling?

Back 44

The cycling of earth materials through living systems and back to the earth. It involves a change in the naturally occurring chemical elements from an inorganic form to an organic molecule and back again.

Hint 44

(pg 27)

Front 45

Name two things all living organisms are dependent upon?

Back 45

-A source of energy.
-A number of inorganic materials that are continuously being cycled throughout the ecosystem (including nutrients).

Hint 45

(pg 27)

Front 46

How is the movement of inorganic materials different from the movement of energy?

Back 46

It is conserved within the ecosystem, its atoms & molecules being used & reused indefinitely.

Hint 46

(pg 27)

Front 47

What are nutrients?

Back 47

40 essential naturally occurring chemical elements that are essential to the existence of living organisms.

Hint 47

(pg 27)

Front 48

What are macronutrients and what are some examples of them?

Back 48

Nutrients that are fairly abundant & are needed in relatively large quantities by plants & animals.

Hint 48

-Carbon
-Hydrogen
-Oxygen
-Nitrogen
-Phosphorus
-Potassium
-Calcium
-Magnesium
-Sulfur
(pg 27)

Front 49

What are trace elements and what are some examples of them?

Back 49

Nutrients that are required in much smaller amounts than macronutrients.

Hint 49

-Iron
-Copper
-Manganese
-Zinc
-Chlorine
-Iodine
(pg 27)

Front 50

What are the two types of biochemical cycles and how do you classify them?

Back 50

Gaseous & sedimentary.

Hint 50

-Depending on whether the primary source for the nutrient involved happens to be air and water, or soil and rocks.
-Note that elements moved by gaseous cycles recycle much more quickly and efficiently than sedimentary cycles.
(pg 28)

Front 51

Discuss two gaseous cycles.

Back 51

-In the carbon cycle, the principal inorganic source of carbon is the carbon dioxide found in the atmosphere and dissolved in bodies of water, but also in storage within deposits of fossil fuels (coal, oil, and gas), but the largest amount is in limestone.
-In the nitrogen cycle, the major reservoirs in the ecosystem are the 78% of nitrogen gas that makes up our atmosphere and the nitrogen stored in rock-forming materials.

Hint 51

(pgs 28-29)

Front 52

What is the general pattern of sedimentary cycles and what could be a consequence of it?

Back 52

It's a downhill one, where materials tend to move through ecosystems into relatively inaccessible geologic pools.

Hint 52

It poses some interesting implications for the stability of ecosystems.
(pg 30)

Front 53

What are ecological successions?

Back 53

Present ecosystems have a dynamic quality of their own, their component communities changing in an orderly sequence within a given area., and this process is called ecological succession.

Hint 53

(pg 30)

Front 54

What are successions and when do they happen?

Back 54

The gradual, step-by-step changes over time in the relative abundance of dominant species within a biotic community.

Hint 54

They follow a disturbance.
(pg 32)

Front 55

What are some events that can cause successional changes?

Back 55

Natural events (fires, high winds, earthquakes, pest outbreaks) and unnatural events (lumbering, grazing).

Hint 55

(pg 35)

Front 56

What is a climax community?

Back 56

A relatively stable, self-perpetuating stage that biotic communities change towards.

Hint 56

Note that the physical environment itself and the composition of the biotic community change slowly over time in a directional manner toward the climax community.
(pg 34)

Front 57

What are pioneer plants and what are some of their features?

Back 57

They are the first stage of succession.

Hint 57

-They're generally small, low-growing species
-Can tolerate severe climatic conditions
-Produce large numbers of spores or seeds annually
-Grow rapidly
-Have short life cycles.
-Intolerant of other organisms.
(pg 34)

Front 58

What is a primary succession?

Back 58

When pioneer organisms colonize an area formerly devoid of life.

Hint 58

(pg 35)

Front 59

What is a secondary succession and give an example of it?

Back 59

When succession proceeds from a state in which other organisms are still present.

Hint 59

Even though the disturbed area appears barren, there may be dormant seeds lying underneath the soil that quickly initiate the process of revegetation, joined by migrant species from outside the area.
(pg 35)

Front 60

Which is more common, primary or secondary succession?

Back 60

Secondary.

Hint 60

(pg 35)

Front 61

How do aquatic successions differ from terrestrial successions?

Back 61

Not all aquatic successions result in the establishment of a terrestrial climax community. If the body of water is very large or deep and there is strong wave action, a stable aquatic community may form & undergo no further change.

Hint 61

(pg 35)

Front 62

Describe the process of eutrophication (nutrient enrichment)?

Back 62

With the accumulation of dead organic material, the supply of nutrients necessary for the growth of algae & microorganisms is increased and they flourish accordingly, proving a food source for fish & other large animals.

Hint 62

(pg 35)