Question 1

Soil texture classification is based on the percent of __________ that make up the soil.

Accepted Answer

A)  air,water,and solids
B)  water and solids
C)  sand,silt,and clay
D)  sand and water
E)  clay and sand C

Question 2

Which of these characterizes dead zones in the ocean?

Accepted Answer

A)  Low temperatures.
B)  Lacking microbial life.
C)  Being hypoxic.
D)  Being oligotrophic.
E)  Lacking nutrients. C

Question 3

Deep subsurface environment are considered to be void of microbial life.

Accepted Answer

A) True 
 B)False  False

Question 4

Due to the environment from which it can be isolated,we can characterize Beggiatoa as: (Select all that apply)

Accepted Answer

A)  Barophilic
B)  Chemolithotrophic
C)  Photolithotrophic
D)  Psychrophilic
E)  oligotrophic

Question 5

A silt loam soil will possess:

Accepted Answer

A)  50% clay,20% sand,10% silt
B)  10% clay,10% sand,80% silt
C)  50% clay,20% sand,80% silt
D)  80% clay,20% sand,15% silt
E)  40% clay,20% sand,10% silt

Question 6

Which of these technologies employs heavy isotopes of nitrogen and carbon to enrich for DNA samples from actively growing organisms?

Accepted Answer

A)  RNA-SIP
B)  Metagenomic sequencing
C)  DDGE
D)  FISH
E)  SSU rRNA sequencing

Question 7

Estimates of overall microbial abundance in the ocean indicate that more Archaea are present than Bacteria.

Accepted Answer

A) True 
 B)False

Question 8

Which of these technologies could be used to determine the related ness of organisms? (Select all that apply)

Accepted Answer

A)  RNA-SIP
B)  Metagenomic sequencing
C)  DDGE
D)  FISH
E)  SSU rRNA sequencing

Question 9

The coastal marine waters contain on average about _________ microbial cells per ml.

Accepted Answer

A)  10
B)  100
C)  10,000
D)  1 million
E)  100 million

Question 10

Where is the soil's rhizosphere?

Accepted Answer

A)  Areas in contact with bodies of water.
B)  Areas in direct contact with the atmosphere.
C)  Areas surrounding plant roots.
D)  Patches that support nitrogen fixation.
E)  Zones that contain animal life.

Question 11

What is the % salinity of the ocean?

Accepted Answer

A)  1% or less
B)  3.5%
C)  8%
D)  15%
E)  35%

Question 12

FISH is a fluorescent microscopic technique used to differentiate microbes using this fluorescently labeled material.

Accepted Answer

A)  antibody
B)  antigen
C)  protein
D)  DNA probe
E)  lipid

Question 13

What are humic substances?

Accepted Answer

A)  clay particles
B)  recalcitrant organic molecules
C)  glucose molecules
D)  carbonates and phosphates
E)  silt and sand

Question 14

The part of the soil that immediately surrounds the plant root is called the __________.

Accepted Answer

The answer of The part of the soil that immediately...

Question 15

Soil microbes surrounding the plant root contribute to plant growth by providing the plants with all of the following EXCEPT:

Accepted Answer

A)  a source of fixed nitrogen.
B)  soluble phosphorus.
C)  water.
D)  a usable carbon source.
E)  protection from pathogens.

Question 16

How mught quorum sensing knowledge assist in medical antibiotic applications?

Accepted Answer

A)  Quorum sensors are antimicrobial in nature and their overexpression and purification may lead to a novel antibiotic class
B)  Quorum sensing inhibition might reduce bacterial communication and toxin release
C)  Quorum sensing stimulation might allow bacteria to outgrow nutrient sources
D)  Quorum sensing stimulation may allow biofilm reduction
E)  All are plausible choices

Question 17

Which of these processes likely contributes LEAST to growth of microbes in subsurface environments

Accepted Answer

A)  Chemolithoautotrophy
B)  Organic detritus deposition from surface layers
C)  Chemolithoheterotrophy
D)  Chemoorganoheterotrophy
E)  All contribute equally

Question 18

Which gel constituents are essential in facilitating DNA strand separation in the DGGE technique? (Select all that apply)

Accepted Answer

A)  Urea gradient
B)  Temperature gradient
C)  GC-rich primer clamp
D)  Polyacrylamide
E)  Applied voltage

Question 19

Which of these represents MOST of the ocean's biomass?

Accepted Answer

A)  fish
B)  sea mammals
C)  fish and sea mammals
D)  marine plants
E)  microbes

Question 20

Approximately what percent of primary production reaches the ocean floor?

Accepted Answer

A)  one
B)  five
C)  ten
D)  twenty
E)  forty

Exam 15: Microbial Ecosystems