MCB3023 EXAM 1 MODULES 1.1-1.4
WITH CORRECT SOLUTIONS
The bacterial chromosome is a highly condensed structure that is tightly wound up
around itself to fit into the bacterial cell. What is the main enzyme responsible for
condensing the DNA? - ANSWER-DNA topoisomerase
The discovery of ribozymes provides evidence that life on the early Earth may have
been based on - ANSWER-RNA
Which of these is considered to be the smallest unit of life? - ANSWER-cell
A chemoautotroph: - ANSWER-obtains carbon and energy from inorganic molecules
Which of the characteristics of life is not displayed by any individual organism? -
ANSWER-evolution
Which is the correct distinction between a heterotroph and an autotroph? -
ANSWER-An autotroph utilizes carbon dioxide as a carbon source and a heterotroph
utilizes organic compounds as a carbon source.
In which of these are Archaea and Bacteria significantly different? - ANSWER-
membrane lipid structure
In which of these aspects do Archaea DIFFER from Eukarya - ANSWER-Being
haploid in chromosome number while Eukarya are diploid
What are the two lines of evidence that support the Endosymbiotic Theory for the
origin of chloroplasts? - ANSWER-They divide by binary fission and they contain
DNA
The eukaryal cell emerged on Earth approximately ______ years ago - ANSWER-2
billion
Movement of the eukaryal cilia and flagella involves interaction between dynein
motor proteins and _____ - ANSWER-microtubules
Which medium is used to obtain maximum yield of any pure culture? - ANSWER-
nutrient-rich general purpose
Which of these methods will NOT ensure sterility? - ANSWER-Pasteurization
Preventing phagocytosis by phagocytic cells
Resisting desiccation
Attachment
, In which molecule is the occurrence of mutations most likely to be detected and
repaired? - ANSWER-double stranded DNA
Which best describes the cyanobacteria? - ANSWER-Carry out oxygenic
photosynthesis
The Endosymbiotic Theory supports - ANSWER-Presence of mitochondria in
eukaryotes
The MreB protein in bacteria may play an important role in - ANSWER-Determining
cell shape
Given the size of a typical ribosome, how many would you expect to find inside a
typical bacterium of 1-5um size? - ANSWER-5-20 ribosomes
During steady state growth in a chemostat, the growth rate of the cells is equivalent
to: - ANSWER-the dilution rate
You are using triple sugar iron agar to differentiate intestinal bacteria. You believe
you have isolated Shigella. What appearance would you see in the culture tube? -
ANSWER-Red slant, yellow butt
Which of these are fossilized microbial mats containing photosynthesis bacteria? -
ANSWER-stromatolites
Which term describes straight, rod-shaped bacteria? - ANSWER-bacilli
Which statement below is false concerning the atmosphere of the early Earth? -
ANSWER-O2 was present in very minute amounts
Which is the major component of the cell wall in the microbes in the Bacteria
domain? - ANSWER-peptidoglycan
Which is an example of an inclusion body found in a bacterial cell? - ANSWER-
polyhydroxybutyrate
The glycan portion of peptidoglycan is composed of alternating units of which two
compounds? - ANSWER-N-acetylmuramic acid and N-acetylglucosamine (NAM and
NAG)
Some bacteria produce sterol-like molecules called __________________ that help
to stabilize the plasma membrane - ANSWER-hopanoids
What is the function of the bacterial capsule? - ANSWER-all of the above:
Which of these constitute valid reasons why action polymer formation by Shigella
should be considered as a strong virulence factor? - ANSWER-Actin can propel
bacterial cells from one side of a host cell to another
WITH CORRECT SOLUTIONS
The bacterial chromosome is a highly condensed structure that is tightly wound up
around itself to fit into the bacterial cell. What is the main enzyme responsible for
condensing the DNA? - ANSWER-DNA topoisomerase
The discovery of ribozymes provides evidence that life on the early Earth may have
been based on - ANSWER-RNA
Which of these is considered to be the smallest unit of life? - ANSWER-cell
A chemoautotroph: - ANSWER-obtains carbon and energy from inorganic molecules
Which of the characteristics of life is not displayed by any individual organism? -
ANSWER-evolution
Which is the correct distinction between a heterotroph and an autotroph? -
ANSWER-An autotroph utilizes carbon dioxide as a carbon source and a heterotroph
utilizes organic compounds as a carbon source.
In which of these are Archaea and Bacteria significantly different? - ANSWER-
membrane lipid structure
In which of these aspects do Archaea DIFFER from Eukarya - ANSWER-Being
haploid in chromosome number while Eukarya are diploid
What are the two lines of evidence that support the Endosymbiotic Theory for the
origin of chloroplasts? - ANSWER-They divide by binary fission and they contain
DNA
The eukaryal cell emerged on Earth approximately ______ years ago - ANSWER-2
billion
Movement of the eukaryal cilia and flagella involves interaction between dynein
motor proteins and _____ - ANSWER-microtubules
Which medium is used to obtain maximum yield of any pure culture? - ANSWER-
nutrient-rich general purpose
Which of these methods will NOT ensure sterility? - ANSWER-Pasteurization
Preventing phagocytosis by phagocytic cells
Resisting desiccation
Attachment
, In which molecule is the occurrence of mutations most likely to be detected and
repaired? - ANSWER-double stranded DNA
Which best describes the cyanobacteria? - ANSWER-Carry out oxygenic
photosynthesis
The Endosymbiotic Theory supports - ANSWER-Presence of mitochondria in
eukaryotes
The MreB protein in bacteria may play an important role in - ANSWER-Determining
cell shape
Given the size of a typical ribosome, how many would you expect to find inside a
typical bacterium of 1-5um size? - ANSWER-5-20 ribosomes
During steady state growth in a chemostat, the growth rate of the cells is equivalent
to: - ANSWER-the dilution rate
You are using triple sugar iron agar to differentiate intestinal bacteria. You believe
you have isolated Shigella. What appearance would you see in the culture tube? -
ANSWER-Red slant, yellow butt
Which of these are fossilized microbial mats containing photosynthesis bacteria? -
ANSWER-stromatolites
Which term describes straight, rod-shaped bacteria? - ANSWER-bacilli
Which statement below is false concerning the atmosphere of the early Earth? -
ANSWER-O2 was present in very minute amounts
Which is the major component of the cell wall in the microbes in the Bacteria
domain? - ANSWER-peptidoglycan
Which is an example of an inclusion body found in a bacterial cell? - ANSWER-
polyhydroxybutyrate
The glycan portion of peptidoglycan is composed of alternating units of which two
compounds? - ANSWER-N-acetylmuramic acid and N-acetylglucosamine (NAM and
NAG)
Some bacteria produce sterol-like molecules called __________________ that help
to stabilize the plasma membrane - ANSWER-hopanoids
What is the function of the bacterial capsule? - ANSWER-all of the above:
Which of these constitute valid reasons why action polymer formation by Shigella
should be considered as a strong virulence factor? - ANSWER-Actin can propel
bacterial cells from one side of a host cell to another
