Definitions

Question 1

ecosystems

Answer 1

a community and its physical environment

Question 2

community

Answer 2

all of the organisms that live and interact in an area at the same time

Question 3

primary producers

Answer 3

organism that incorporates simple inorganic substances such as carbon dioxide into organic molecules, providing potential food sources for other organisms

Question 4

consumers

Answer 4

organism that consumes other organisms as a source of carbon and energy

Question 5

decomposers

Answer 5

organism that consumes dead organisms as a source of carbon and energy , releasing simple organic products

Question 6

guilds

Answer 6

a group of organisms that carry out similar processes

Question 7

chemosynthesis

Answer 7

metabolic process that derives energy from chemical rather than from light

Question 8

niche

Answer 8

specific functional role of an organism within an ecosystem

Question 9

Denaturing gradient gel electrophoresis (DGGE)

Answer 9

technique that allows electrophoretic separation of DNA fragments based upon DNA sequence differences rather than size

Question 10

fluorescent in situ hybridization (FISH)

Answer 10

technique that detects specific nucleotide sequences using fluorescently labeled oligonucleotide probes

Question 11

flow cytometry

Answer 11

method of detecting cells in suspension by measuring scattering of light as the cells pass by a laser beam

Question 12

stable isotope probe (SIP)

Answer 12

technique that exposes organisms to specific nutrient molecules labeled with carbon 13 or nitrogen 15, thus labeling their DNA which can later be extracted and analyzed

Question 13

operational taxonomic unit (OTU)

Answer 13

group of organisms that shares at least 97% SSU rRNA gene sequence identity

Question 14

oligotrophy

Answer 14

use of nutrients present in very low concentrations

Question 15

phytoplankton

Answer 15

drifting photosynthetic microorganisms that are primary producers in the ocean

Question 16

zooplankton

Answer 16

drifting non-photosynthetic microorganisms that act as consumers in the ocean

Question 17

piezophiles

Answer 17

organism that can withstand high pressure

Question 18

dilution to extinction

Answer 18

technique that produces a dilute soltion from which samples that contain individual cells can be grown to produce a pure culture

Question 19

thermocline

Answer 19

layer of water in deep lakes that separates warmer, lower-density water from lower colder high-density water; characterized by rapid change in temperature and density

Question 20

biome

Answer 20

major category of ecosystem characterized by vegetation and climate

Question 21

horizons

Answer 21

layer of soil with distinct characteristics

Question 22

humic material

Answer 22

product of incomplete breakdown of plant biomass found in soil

Question 23

rhizosphere

Answer 23

region of soil immediately surrounding plant roots

Question 24

bioremediation

Answer 24

use of microorganisms to degrade environmental pollutants

Question 25

xenobiotics

Answer 25

chemical not naturally found in or produced by organisms; usually not degraded by microorganisms

Question 26

biostimulation

Answer 26

addition of oxygen or limiting nutrients to increase the metabolic activity of microorganisms that degrade organic wastes or pollutants

Question 27

cometabolism

Answer 27

metabolic transformation of a molecule that is not used as a carbon or energy source

Question 28

bioaugmentation

Answer 28

introduction of microorganisms that increase the rate of degradation of organic wastes or pollutants

Question 29

terminal restriction fragment length polymorphism (TRFLP)

Answer 29

technique to profile DNA in a microbial community using position of a restriction site closest to a labeled end of an amplified gene, usually the SSU rRNA gene