Chapter 7

Question 1

basic requirements for life

Answer 1

Bioelements

Question 2

substance (element or compound)
an organism must get from a source outside its cells

Answer 2

Essential nutrients

Question 3

contain carbon and hydrogen atoms
and are usually the products of living things

Answer 3

Organic nutrients

Question 4

atom or molecule that contains a
combination of atoms other than carbon and hydrogen

Answer 4

Inorganic nutrients

Question 5

must obtain carbon in an organic form
such as proteins, carbohydrates, lipids, and nucleic acids
made by other living organisms

Answer 5

Heterotroph

Question 5

Produce oxygen and use chlorophyll as the primary pigment

Answer 5

Oxygenic photosynthesis

Question 6

an organism that uses CO2, an inorganic
gas, as its carbon source

Answer 6

Autotroph

Question 7

gain energy from chemical compounds

Answer 7

Chemotroph

Question 8

uses CO2 as source

Answer 8

Autotroph

Question 9

What are the two categories of chemoorganotrophs?

Answer 9

Saprobes and symbionts

Question 9

survive totally on
inorganic substances

Answer 9

Chemoautotrophs (lithoautotrophs)

Question 10

no oxygen but sulfur production, use bacteriochlorophyll as pigment

Answer 10

Anoxygenic photosynthesis

Question 11

a kind of chemoautotroph, produce
methane gas under anaerobic conditions

Answer 11

Methanogens

Question 12

free-living microorganisms that feed on organic
detritus from dead organisms

Answer 12

Saprobes

Question 13

derive nutrients from host
* Can obtain nutrients from living or nonliving source
* Some are obligate parasites

Answer 13

Symbionts

Question 14

If an organism is degrading large organic molecules to get
both carbon and energy, it would be best described as a:
A. Photoheterotroph
B. Photoautotroph
C. Chemoorganotroph
D. Chemoautotroph

Answer 14

C. Chemoorganotroph

Question 15

does not require energy; substances
exist in a gradient and move from areas of higher
concentration toward areas of lower concentration

Answer 15

Passive transport

Question 16

cannot grow without oxygen

Answer 16

Obligate aerobe

Question 17

utilizes oxygen but can also grow
in its absence

Answer 17

Facultative anaerobe

Question 18

lacks the enzymes to detoxify
oxygen so cannot survive in an oxygen environment

Answer 18

Obligate anaerobe

Question 18

requires only a small amount of oxygen

Answer 18

Microaerophile

Question 19

utilizes oxygen and can detoxify it

Answer 19

Aerobe

Question 19

require a high concentration of salt

Answer 19

Osmophiles

Question 20

does not utilize oxygen

Answer 20

Anaerobe

Question 21

grows best at higher CO2 tensions than
normally present in the atmosphere

Answer 21

Capnophile

Question 22

do not utilize oxygen but can
survive and grow in its presence

Answer 22

Aerotolerant anaerobes

Question 23

grow within range of pH 5.5 to 8

Answer 23

Neutrophiles

Question 24

grow optimally in solutions of 25% NaCl but
require at least 9% NaCl

Answer 24

Obligate halophiles

Question 25

do not require high concentration of
solute

Answer 25

Osmotolerant –

Question 26

remarkably resistant to salt

Answer 26

Facultative halophiles

Question 27

can survive under extreme pressure and will
rupture if exposed to normal atmospheric pressure

Answer 27

Barophiles –

Question 28

Members cooperate and share nutrients

Answer 28

Syntrophy

Question 29

Some members are inhibited or destroyed
by others

Answer 29

Amensalism

Question 30

both members benefit

Answer 30

Mutualism –

Question 31

can be separated and live apart

Answer 31

Nonobligate Mutualism

Question 31

commensal benefits, other member
neither harmed nor benefited

Answer 31

Commensalism

Question 32

require each other to survive

Answer 32

Obligate Mutualism

Question 33

Division of bacterial cells occurs mainly through

Answer 33

binary fission

Question 34

When organisms are free-living in a shared habitat

Answer 34

Non-symbiotic

Question 35

Each new fission cycle increases the population by a factor
of __

Answer 35

2