Environmental Science Hit Parade: Chapter 4

Front 1

ammonification

Back 1

the production of ammonia or ammonium compounds in the decomposition of organic matter, especially through the action of bacteria.

Front 2

assimilation

Back 2

the process in which plants absorb ammonium (NH3), ammonia ions (NH4+), and nitrate ions (NO3) through their roots.

Front 3

autotroph

Back 3

an organism that obtains organic food molecules without eating other organisms or substances derived form other organisms. They use energy from the sun or from the oxidation of inorganic substances to make organic molecules from inorganic ones.

Front 4

bioaccumulation

Back 4

the accumulation of a substance, such as a toxic chemical, in various tissues of a living organism.

Front 5

biomagnification

Back 5

the process by which the concentration of toxic substances increases in each successive link in the food chain.

Front 6

biosphere

Back 6

the part of the Earth and its atmosphere in which living organisms exist or that is capable of supporting life.

Front 7

carnivore

Back 7

an animal that only consumes other animals.

Front 8

chemotroph (chemoautotroph)

Back 8

an organism, such as a bacterium or protozoan, that obtains its nourishment through the oxidation of inorganic chemical compounds, as opposed to photosynthesis.

Front 9

climax community

Back 9

a stable, mature community in a successive series that has reached equilibrium after having evolved through stages and adapted to its environment.

Front 10

combustion

Back 10

the process of burning.

Front 11

commnity

Back 11

formed form populations of different species occupying the same geographic area.

Front 12

competitive exclusion

Back 12

the process that occurs when two different species in a region compete and the better adapted species wins.

Front 13

consumer

Back 13

an organism that must obtain food energy from secondary sources, for example, by eating plant or animal matter.

Front 14

decomposer

Back 14

bacteria or fungi that absorb nutrients from nonliving organic matter like plant material, the wastes of living organisms, and corpses. They convert these materials into inorganic forms.

Front 15

denitrification

Back 15

the process by which specialized bacteria (mostly anaerobic bacteria) convert ammonia to NO3, NO2, and N2 and release it back into the atmosphere.

Front 16

detritivore

Back 16

organisms that derive energy from consuming nonliving organic matter.

Front 17

ecological succession

Back 17

transition in species composition of a biological community, often following ecological disturbance of the community; the establishment of a biological community in any area virtually barren of life.

Front 18

edge effect

Back 18

the condition in which, at ecosystem boundaries, there is greater species diversity and biological intensity than there is in the heart of the ecological communities.

Front 19

evaporation

Back 19

to convert or change into a vapor.

Front 20

evolution

Back 20

change in the genetic composition of a population during successive generations as a result of natural selection acting on the genetic variation among individuals and resulting in the development of new species.

Front 21

extinction

Back 21

being extinct or the process of becoming extinct.

Front 22

food chain

Back 22

a succession of organisms in an ecological community that constitutes a continuation of food energy from one organism to another as each consumes a lower member and, in turn, is preyed upon by a higher member.

Front 23

food web

Back 23

a complex of interrelated food chains in an ecological community.

Front 24

Gause's principle

Back 24

states that no two species can occupy the same niche at the same time, and that the species that is less fit to live in the environment will either relocate, die out, or occupy a smaller niche.

Front 25

Gross Primary Productivity

Back 25

the amount of sugar that the plants produce in photosynthesis, and subtracting from it the amount of energy the plants need for growth, maintenance, repair, and reproduction.

Front 26

habitat

Back 26

the area or environment where an organism or ecological community normally lives or occurs.

Front 27

habitat fragmentation

Back 27

when the size of an organism's natural habitat is reduced, or when development occurs that isolates a habitat.

Front 28

heterotroph

Back 28

an organism that cannot synthesize its own food and is dependent on complex organic substances for nutrition.

Front 29

indigenous species

Back 29

species that originate and live, or occur naturally, in an area or environment.

Front 30

invasive species

Back 30

and introduced, nonnative species.

Front 31

keystone species

Back 31

a species whose very presence contributes to an ecosystem's diversity and whose extinction would consequently lead to the extinction of other forms of life.

Front 32

Law of Conservation of Matter

Back 32

states that matter can neither be created nor destroyed.

Front 33

mutualism

Back 33

a symbiotic relationship in which both species benefit.

Front 34

natural selection

Back 34

the process by which, according to Darwin's theory of evolution, only the organisms best adapted to their environment tend to survive and transmit their genetic characteristics in increasing numbers to succeeding generations, while those less adapted tend to be eliminated.

Front 35

Net Primary Productivity (NPP)

Back 35

the amount of energy that plants pass on to the community of herbivores in an ecosystem.

Front 36

niche

Back 36

the total sum of a species' use of the biotic and abiotic resources in its environment.

Front 37

nitrification

Back 37

the process in which soil bacteria convert ammonium (NH4+) to a form that can be used by plants; nitrate, or NO3.

Front 38

nitrogen fixation

Back 38

the conversion of atmosphere nitrogen into compounds, such as ammonia, by natural agencies or various industrial processes.

Front 39

photosynthesis

Back 39

the process in green plants and certain other organisms by which carbohydrates are synthesized from carbon dioxide and water using light as an energy source. Usually releases oxygen as a byproduct.

Front 40

realized niche

Back 40

when a species occupies a smaller niche than it would in the absence of competition.

Front 41

reservoir

Back 41

a place where a large quantity of a resource sits for a long period of time.

Front 42

respiration

Back 42

the process in which animals (and plants!) breathe and give off carbon dioxide from cellular metabolism.

Front 43

residency time

Back 43

the amount of time a resource spends in a reservoir or an exchange pool.

Front 44

transpiration

Back 44

the act of process of transpiring, or releasing water vapor, especially through the stomata of plant tissue or the pores of the skin.

Front 45

trophic pyramid (energy pyramid)

Back 45

the structure obtained if we organize the amount of energy contained in producers and consumers in an ecosystem by kilocalories per square meter, from largest to smallest.