BIO 2020 EXAM 2 2026/2027 – BIOLOGY STUDY GUIDE, PRACTICE QUESTIONS,
EXAM REVIEW & TEST PREP
Prokaryotes are classified as belonging to two different domains. What are the domains? - correct
answer ✔✔Bacteria and Archaea
What organisms are most numerous on Earth?
-Eukaryotes
-Archaea
-Prokaryotes
-Plants
-Insects - correct answer ✔✔prokaryotes
To establish a link between a specific bacterium and a skin disease, researchers have shown that the
bacterium was present in sick persons but not in healthy individuals. They isolate the bacterium in a pure
culture and demonstrated that experimental healthy animals inject with this culture became sick. What
other experiment do researchers need to perform to be absolutely sure that the bacterium is responsible
for the disease?
-Demonstrate that the bacterium belongs to the pathogenic lineage
-Demonstrate that the bacterium is not able to live outside of humans or animals.
-Isolate bacterium from an infected sick animal and demonstrate that it is the same bacterium as the one
used for infection
-Isolate Bacterium from an infected sick animal and demonstrate that it is susceptible to broad spectrum
antibiotics. - correct answer ✔✔Isolate bacterium from an infected sick animal and demonstrate that it
is the same bacterium as the one used for infection.
You need to identify the major type of bacteria living on the shower curtain in your bathroom and find
out what they use as a food source. What is the most efficient method for answering the question?
-Enrichment culture
-Producing
-Direct sequencing
-Enrichment culture and direct sequencing are equally efficient methods. - correct answer
✔✔Enrichment culture
you might be interested to know how many different types of bacteria live on the shower curtain in your
bathroom. What is the most efficient method for finding out?
-Producing a molecular phylogeny
-Enrichment culture
-Direct sequencing
-Enrichment culture and direct sequencing are equally methods. - correct answer ✔✔Direct Sequencing
, Microbiologists use the gram stain to aid in the identification of bacteria. What is the major difference
between Gram-positive and gram-negative bacteria?
-Structure of nucleotides in the plasma membrane
-Presence or Absence of muramic acid in the cell wall
- presence or absence of peptidoglycan in the cell wall
-Presence or absence of outer plasma membrane - correct answer ✔✔presence or absence of
peptidoglycan in the cell wall
A prokaryote that obtains energy and carbon as it decomposes dead organisms is a
-Autotroph
-Chemotroph
-Autotroph and Phototroph
-Heterotroph and Chemotroph
-Autotroph, phototroph, and chemotroph - correct answer ✔✔Heterotroph and chemotroph
Which of the following extremophiles might researchers most likely use as a model for the earliest
organisms on earth?
-Bacterium capable of living at extremely high salinity
-Bacterium found on another planet or moon
-Archaean capable of surviving in the polar ice caps.
-An anaerobic Archaean species. - correct answer ✔✔An anaerobic Archaean species
you run an osteology lab, where students can study the bone structure of various species. to produce
clean bones, you introduce insects and bacteria to remove all remaining flesh. Which bacteria would be
the best purchase for your lab?
-Crenarchaeota
-Actinobacteria
-Alveolata
-Cyanobacteria
-Proteobacteria - correct answer ✔✔Actinobacteria
you have found a new prokaryote. What line of evidence would support your hypothesis that the
organism is a cyanobacterium?
-It is able to form colonies and produce oxygen
-It is an endosymbiont
-It forms chains call mycelia
-You determine that it can cause lime disease
-It lacks a cell wall - correct answer ✔✔it is able to form colonies and produce oxygen.
Protistic and bacteria are grouped into different domains because
-Protist can eat bacteria
-Bacteria are not made of cells
EXAM REVIEW & TEST PREP
Prokaryotes are classified as belonging to two different domains. What are the domains? - correct
answer ✔✔Bacteria and Archaea
What organisms are most numerous on Earth?
-Eukaryotes
-Archaea
-Prokaryotes
-Plants
-Insects - correct answer ✔✔prokaryotes
To establish a link between a specific bacterium and a skin disease, researchers have shown that the
bacterium was present in sick persons but not in healthy individuals. They isolate the bacterium in a pure
culture and demonstrated that experimental healthy animals inject with this culture became sick. What
other experiment do researchers need to perform to be absolutely sure that the bacterium is responsible
for the disease?
-Demonstrate that the bacterium belongs to the pathogenic lineage
-Demonstrate that the bacterium is not able to live outside of humans or animals.
-Isolate bacterium from an infected sick animal and demonstrate that it is the same bacterium as the one
used for infection
-Isolate Bacterium from an infected sick animal and demonstrate that it is susceptible to broad spectrum
antibiotics. - correct answer ✔✔Isolate bacterium from an infected sick animal and demonstrate that it
is the same bacterium as the one used for infection.
You need to identify the major type of bacteria living on the shower curtain in your bathroom and find
out what they use as a food source. What is the most efficient method for answering the question?
-Enrichment culture
-Producing
-Direct sequencing
-Enrichment culture and direct sequencing are equally efficient methods. - correct answer
✔✔Enrichment culture
you might be interested to know how many different types of bacteria live on the shower curtain in your
bathroom. What is the most efficient method for finding out?
-Producing a molecular phylogeny
-Enrichment culture
-Direct sequencing
-Enrichment culture and direct sequencing are equally methods. - correct answer ✔✔Direct Sequencing
, Microbiologists use the gram stain to aid in the identification of bacteria. What is the major difference
between Gram-positive and gram-negative bacteria?
-Structure of nucleotides in the plasma membrane
-Presence or Absence of muramic acid in the cell wall
- presence or absence of peptidoglycan in the cell wall
-Presence or absence of outer plasma membrane - correct answer ✔✔presence or absence of
peptidoglycan in the cell wall
A prokaryote that obtains energy and carbon as it decomposes dead organisms is a
-Autotroph
-Chemotroph
-Autotroph and Phototroph
-Heterotroph and Chemotroph
-Autotroph, phototroph, and chemotroph - correct answer ✔✔Heterotroph and chemotroph
Which of the following extremophiles might researchers most likely use as a model for the earliest
organisms on earth?
-Bacterium capable of living at extremely high salinity
-Bacterium found on another planet or moon
-Archaean capable of surviving in the polar ice caps.
-An anaerobic Archaean species. - correct answer ✔✔An anaerobic Archaean species
you run an osteology lab, where students can study the bone structure of various species. to produce
clean bones, you introduce insects and bacteria to remove all remaining flesh. Which bacteria would be
the best purchase for your lab?
-Crenarchaeota
-Actinobacteria
-Alveolata
-Cyanobacteria
-Proteobacteria - correct answer ✔✔Actinobacteria
you have found a new prokaryote. What line of evidence would support your hypothesis that the
organism is a cyanobacterium?
-It is able to form colonies and produce oxygen
-It is an endosymbiont
-It forms chains call mycelia
-You determine that it can cause lime disease
-It lacks a cell wall - correct answer ✔✔it is able to form colonies and produce oxygen.
Protistic and bacteria are grouped into different domains because
-Protist can eat bacteria
-Bacteria are not made of cells
