Chapter 26

Question 1

One of the three monophyletic domains of life, consisting of single-celled organisms with a single circular chromosome but no nucleus that divide by binary fission and differ from archaeons in many aspects of their cell and molecular biology.

Answer 1

Bacteria

Question 2

One of the three domains of life, consisting of single-celled organisms with a single circular chromosome and no true nucleus that divide by binary fission and differ from bacteria in many aspects of their cell and molecular biology.

Answer 2

Archaea

Question 3

A complex polymer of sugars and amino acids that makes up the cell wall.

Answer 3

peptidoglycan

Question 4

The transfer of genetic material between organisms that are not parent and offspring.

Answer 4

horizontal gene transfer

Question 5

The direct cell-to-cell transfer of DNA, usually in the form of a plasmid.

Answer 5

Conjugation

Question 6

The conversion of cells from one state to another, as from nonvirulent to virulent, when DNA released to the environment by cell breakdown is taken up by recipient cells. In recombinant DNA technology, the introduction of recombinant DNA into a recipient cell.

Answer 6

Transformation

Question 7

Horizontal gene transfer by means of viruses.

Answer 7

Transduction

Question 8

Producing oxygen.

Answer 8

Oxygenic

Question 9

Utilizing oxygen.

Answer 9

Aerobic

Question 10

Not producing oxygen; anoxygenic photosynthetic bacteria do not gain electrons from water and so do not generate oxygen gas.

Answer 10

Anoxygenic

Question 11

A light-harvesting pigment closely related to the chlorophyll found in plants, algae, and cyanobacteria.

Answer 11

bacteriochlorophyll

Question 12

A process of breaking down pyruvate through a wide variety of metabolic pathways that extract energy from fuel molecules such as glucose; the partial oxidation of complex carbon molecules to molecules that are less oxidized than carbon dioxide.

Answer 12

Fermentation

Question 13

An organism that uses the energy from sunlight to make ATP and relies on organic molecules obtained from the environment as the source of carbon for growth and other vital functions.

Answer 13

photoheterotroph

Question 14

A microorganism that obtains energy from chemical compounds, not from sunlight.

Answer 14

chemoautotroph

Question 15

An organism that takes up inorganic carbon, nitrogen, phosphorus, and other compounds from the environment and converts them into organic compounds that will provide food for other organisms in the local environment.

Answer 15

primary producer

Question 16

The process by which organisms take up nutrients from the environment.

Answer 16

assimilation

Question 17

The process in which nitrogen gas (N2) is converted into ammonia (NH3), a form biologically useful to primary producers.

Answer 17

nitrogen fixation

Question 18

The process by which chemoautotrophic bacteria oxidize ammonia (NH3) to nitrite (NO2−) and then nitrate (NO3−).

Answer 18

Nitrification

Question 19

The process in which some bacteria use nitrate as an electron acceptor in respiration.

Answer 19

Dentrification

Question 20

Anaerobic ammonia oxidation; energy metabolism in which ammonium ion is oxidized by nitrite, yielding nitrogen gas as a by-product.

Answer 20

Anammox

Question 21

The episodic loss of diversity as a successful variant outcompetes others.

Answer 21

periodic selection

Question 22

The most diverse bacterial group, defined largely by similarities in rRNA gene sequences; it includes many of the organisms that populate the expanded carbon cycle and other biogeochemical cycles.

Answer 22

proteobacteria

Question 23

Bacteria that retain, in their thick peptidoglycan walls, the diagnostic dye developed by Hans Christian Gram. (Bacteria with thin walls, which do not retain the dye, are said to be gram negative.)

Answer 23

gram-positive bacteria

Question 24

A monophyletic group of bacteria capable of oxygenic photosynthesis.

Answer 24

cyanobacteria

Question 25

One of the three major divisions of Archaea; includes acid-loving microorganisms.

Answer 25

Crenarchaeota

Question 26

One of the three major divisions of Archaea; includes acid-loving, heat-loving, methane-producing, and salt-loving microorganisms.

Answer 26

Euryarchaeota

Question 27

One of the three major divisions of Archaea; thaumarchaeota are chemotrophs, deriving energy from the oxidation of ammonia.

Answer 27

Thaumarchaeota

Question 28

An organism that requires an environment with high temperature.

Answer 28

hyperthermophile

Question 29

Euryarchaeotes that generate natural gas (methane, CH4).

Answer 29

methanogens

Question 30

A layered structure that records sediment accumulation by microbial communities.

Answer 30

stromatolite

Question 31

The process in which species evolve together, each responding to selective pressures from the other.

Answer 31

coevolution