microbes in various habitats

Question 1

what percentage of the water that covers the earth’s surface is marine water

Answer 1

96%

Question 2

T or F: the majority of life in the ocean consists of microorganisms

Answer 2

true

Question 3

there are ___ organisms/ml of water in the costal marine environment

Answer 3

10^8

Question 4

list some physical factors that play a role in supporting microbial life in the ocean (5)

Answer 4

pH, temp, light penetration, amount of dissolved oxygen, pressure

Question 5

list the 3 ocean zones

Answer 5

surface zone (photic zone)
dark mid-water zone
deep sea zone (aphotic zone)

Question 6

how many meters deep is the surface zone

Answer 6

200m

Question 7

how many meters deep is the deep water zone

Answer 7

+ 1000m

Question 8

what microbes are located in the surface zone

Answer 8

photosynthetic microbes, and some heterotrophic bacteria/archaea

Question 9

T or F: there is a tight recycling of nutrients in the surface zone

Answer 9

true

Question 10

why is it good that there is tight recycling of nutrients in the surface zone

Answer 10

it aids in the survival of microbes (referred to as the microbial loop)

Question 11

T or F: there is photosynthesis in the dark mid-water zone

Answer 11

false; there is no photosynthesis taking place

Question 12

how do microbes obtain nutrients in the dark mid-water zone

Answer 12

marine snow

Question 13

what is marine snow? give some examples of what it’s made of

Answer 13

organic matter produced in the upper level that’s hard to degrade and falls through the depths. Can be made of fecal pellets or diatom frustules

Question 14

what happens to the microbes that colonize marine snow

Answer 14

they form a biofilm and work together to degrade the snow

Question 15

what happens as biofilm microbes are degrading marine snow?

Answer 15

it attracts free swimming microbes which help to further degrade the snow

Question 16

__% of the photosynthetically derived carbon reaches the ocean floor

Answer 16

1%

Question 17

T or F: the ocean sediments are the earth’s largest microbial habitat

Answer 17

true

Question 18

list 3 characteristics of microbes in the deep sea zone

Answer 18

barophilic, psychrophilic, grow very slowly

Question 19

what domain of microbes were found in the mariana trench

Answer 19

bacteria

Question 20

T or F: there are naturally occurring oil-eating microbes

Answer 20

true

Question 21

give an example of a species of oil-eating microbes

Answer 21

Alcanivorax sp.

Question 22

there are about __x more viruses in the ocean than bacteria and archaeons combined

Answer 22

10x

Question 23

list 2 ways to quantitate marine viruses

Answer 23

electron microscopy, fluorescent microscopy

Question 24

what percentage of viral genomes from the ocean have no match on any database

Answer 24

90%

Question 25

list 3 roles of viruses in the ocean

Answer 25

major players in microbial mortality, play a role in supplying ecosystems with nutrients, play a role in HGT (transduction)

Question 26

where is the largest fraction of freshwater on earth

Answer 26

frozen at the earth’s polar regions (glaciers)

Question 27

which domain dominates the prokaryotic glacial ice community

Answer 27

bacteria

Question 28

T or F: the bacterial communities isolated from glaciers are dormant

Answer 28

false; they are active

Question 29

bacteria belonging to more than ___ different phyla have been identified in the soil

Answer 29

35

Question 30

describe how there is life in the soil (how do soil bacteria get oxyegn)

Answer 30

soil may have pores within a thin film of water that accumulates. Bacteria utilize the oxygen that diffuses into that water

Question 31

largest phylum of gram negative bacteria in the soil?

Answer 31

Proteobacteria

Question 32

largest phylum of gram positive bacteria in the soil?

Answer 32

Actinobacteria

Question 33

which phylum does genus streptomyces belong to

Answer 33

actinobacteria

Question 34

the number of archaea in the soil depends on what?

Answer 34

carbon:nitrogen ratio

Question 35

more ___ in the soil = more archaea in the soil

Answer 35

nitrogen

Question 36

T or F: fungi are important members of the soil microbial community

Answer 36

true

Question 37

list 2 things that viruses in the soil do

Answer 37

have been found to contain genes to degrade CHOs, they play a role in biogeochemical cycling