Prescotts Microbiology Chapter 7
The reproductive strategies of a Eukaryotic Microbe? - (correct Answer) - - Asexual
and sexual. Both have a sexual and an asexual part of the cycle.
- Haploid or diploid
The reproductive strategies of Bacteria and Archaea? - (correct Answer) - - Haploid
Only
- Asexual-
- All must replicate and segregate their genome prior to cell division
Asexual in Bacteria and Archaea - (correct Answer) - binary fission, budding,
filamentous
Sequence of events from formation of new cell through the next cell division.
Associated with binary fission. - (correct Answer) - Bacterial Cell Cycle
What two pathways function during the Bacterial Cell Cycle? - (correct Answer) - -
DNA replication and partition
- Cytokinesis
Site at which replication begins - (correct Answer) - Single origin of replication
Site at which replication is terminated, located opposite of the origin - (correct
Answer) - Terminus
Group of proteins needed for DNA synthesis - (correct Answer) - Replisome
Most bacterial chromosomes are: - (correct Answer) - circular
DNA replication process in what direction from the orgin which move to opposite
ends of the cell? - (correct Answer) - Both directions
Formation of cross walls between daughter cells - (correct Answer) - Septation
In septation, which step occurs first? - (correct Answer) - Selection of site for
septum formation
In septation, what is the second step that occurs? - (correct Answer) - Assembly of
Z ring
The Z ring is composed of? - (correct Answer) - protein FtsZ
In septation, the third step that occurs is? - (correct Answer) - Assembly of cell
wall synthesizing machinery
In septation, what is the last step that occurs? - (correct Answer) - Constriction
of cell and septum formation
Tubulin homologue, found in most bacteria and archaea. Polymerization forms Z ring,
filaments of meshwork. - (correct Answer) - Protein FtsZ
Oscillate from one side of cell to the other. High concentration of MinC at poles
preventts formation of Z ring at those locations. - (correct Answer) - MinCDE,
limits Z ring to cell center
Anchoring proteins link Z ring to the plasma membrane - (correct Answer) - Divisome
Forms
Cell wall- synthesizing machinery assembled - (correct Answer) - Divisome Forms
The Z ring constricts, the plasma membrane invaginates, and septal wall synthesis/
division is completed - (correct Answer) - Divisome Forms
Sensitive to osmostic concentration of the environment - (correct Answer) - Plasma
Membranes
Water moves into a cell and can cause lysis - (correct Answer) - Hypotonic
Conditions
Hypotonic Conditions can occur if it is not controlled by? - (correct Answer) -
Inclusion bodies, Mechanosensitive channels, and cell walls.
Remove solutes from cytoplasm - (correct Answer) - Inclusion bodies
"relief valve" proteins that form pores that open to release solutes as the
membrane stretches due to influx of water - (correct Answer) - Mechanosensitive
Channels
Prevent membrane from bursting - (correct Answer) - Cell Wall
Water moves out of a cell leading to plasmolysis if not controlled by increasing
compatible solutes - (correct Answer) - Hypertonic Conditions
Water availablity is affected by the interaction of solute molecules or the binding
of water to the surface of the solid. (inversely related to osmotic pressure) -
(correct Answer) - Water Activity
, Microbes adapt to low water activity by being: - (correct Answer) - Osmotolerant
and Halophilic
Able to grow over a wide range of osmotic concentrations - (correct Answer) -
Osmotolerant
Requires high salt concentrations to support growth( possess altered proteins and
membranes to accomodate the high level of salts) - (correct Answer) - Halophilic
A measure of hydrogen ion (H+) activity of a solution - (correct Answer) - pH
pH 0.0 (1.0 MH+) - (correct Answer) - Highly Acidic
pH 14.0 (1 x 10^-14 M H+) - (correct Answer) - Highly Basic
Microbes can be categorized based upon their - (correct Answer) - ph growth range
and pH growth optimum
pH 0 - 5.5 - (correct Answer) - Acidophiles
pH 5.5 - 8.0 - (correct Answer) - Neutrophiles
pH 8.5 to 11.5 - (correct Answer) - Alkalophiles
Most microbes maintain an internal pH near - (correct Answer) - neutrality
The plasma membrane is impermeable to proton. Exchange potassium for protons. -
(correct Answer) - When microbes are near neutrality
Pump protons out of the cell. Some synthesize acid and heat shock proteins that
protect proteins - (correct Answer) - Acidic tolerance response
Many microorganisms change the pH of their habitat by - (correct Answer) -
Producing acidic or basic waste products
The two ways microbial metabolism is affected by temperature - (correct Answer) -
Slowing reactions
Damaging Proteins
Slowing reactions - (correct Answer) - low temperature
Damaging proteins - (correct Answer) - high temperatures
Microbes have cardinal temperatures for - (correct Answer) - Maximal, optimal and
minimal growth
Cardinal Temperatures can be influenced by: - (correct Answer) - Environmental
conditions (pH, available nutrients)
Grow well at 0C, optimally at lower.
- Enzyme systems function very well at low temperatures
- Have high levels of unsaturated fatty acids in their cell membranes, permitting a
semifluid state at low temperatures. - (correct Answer) - Psychrophiles
Grow between 0C - 7C, optimally between 20C and 30C, maximum at 35C - (correct
Answer) - Psychotrophs ( Faculatative Psychrophiles)
Grow between 15C to 20C, optimally 20C-45C, maximum 45 or lower - (correct Answer)
- Mesophiles
Most microbes fall in this category - (correct Answer) - Mesophile
All human pathogens are? Since human body temperature remains steady near 35C -
(correct Answer) - Mesophile
Growth minimum near 45C, optimally between 55C- 65C
- highly heat stable proteins b/c hydrophobic interiors, more noncovalent bonds and
large amounts of non flexible amino acids
-Stabilized by special histone- like proteins
- Membranes contain higher molecular weight lipids that are mmosre saturated and
branch, giving stability - (correct Answer) - Thermophiles
Growth above 90C, growth maximum above 100C, with ranges between 80C and 113C -
(correct Answer) - Hyperthermophiles
Microbes can be categorized according to their usage ( or not) of oxygen - (correct
Answer) - Oxygen Concentration
Microbe able to grow in the presence of O2 - (correct Answer) - Aerobe
Microbe able to grow in the absence of O2 - (correct Answer) - Anaerobe
dependent upon the presence of O2 as the final electron acceptor in respiration.
Superoxide dismutase is present (SOD+)
- Catalase is present (Cat+) - (correct Answer) - Obligate Aerobe
Do not require the presence of O2, but does grow better when it is present (can use
aerobic respiration)
-SOD+
The reproductive strategies of a Eukaryotic Microbe? - (correct Answer) - - Asexual
and sexual. Both have a sexual and an asexual part of the cycle.
- Haploid or diploid
The reproductive strategies of Bacteria and Archaea? - (correct Answer) - - Haploid
Only
- Asexual-
- All must replicate and segregate their genome prior to cell division
Asexual in Bacteria and Archaea - (correct Answer) - binary fission, budding,
filamentous
Sequence of events from formation of new cell through the next cell division.
Associated with binary fission. - (correct Answer) - Bacterial Cell Cycle
What two pathways function during the Bacterial Cell Cycle? - (correct Answer) - -
DNA replication and partition
- Cytokinesis
Site at which replication begins - (correct Answer) - Single origin of replication
Site at which replication is terminated, located opposite of the origin - (correct
Answer) - Terminus
Group of proteins needed for DNA synthesis - (correct Answer) - Replisome
Most bacterial chromosomes are: - (correct Answer) - circular
DNA replication process in what direction from the orgin which move to opposite
ends of the cell? - (correct Answer) - Both directions
Formation of cross walls between daughter cells - (correct Answer) - Septation
In septation, which step occurs first? - (correct Answer) - Selection of site for
septum formation
In septation, what is the second step that occurs? - (correct Answer) - Assembly of
Z ring
The Z ring is composed of? - (correct Answer) - protein FtsZ
In septation, the third step that occurs is? - (correct Answer) - Assembly of cell
wall synthesizing machinery
In septation, what is the last step that occurs? - (correct Answer) - Constriction
of cell and septum formation
Tubulin homologue, found in most bacteria and archaea. Polymerization forms Z ring,
filaments of meshwork. - (correct Answer) - Protein FtsZ
Oscillate from one side of cell to the other. High concentration of MinC at poles
preventts formation of Z ring at those locations. - (correct Answer) - MinCDE,
limits Z ring to cell center
Anchoring proteins link Z ring to the plasma membrane - (correct Answer) - Divisome
Forms
Cell wall- synthesizing machinery assembled - (correct Answer) - Divisome Forms
The Z ring constricts, the plasma membrane invaginates, and septal wall synthesis/
division is completed - (correct Answer) - Divisome Forms
Sensitive to osmostic concentration of the environment - (correct Answer) - Plasma
Membranes
Water moves into a cell and can cause lysis - (correct Answer) - Hypotonic
Conditions
Hypotonic Conditions can occur if it is not controlled by? - (correct Answer) -
Inclusion bodies, Mechanosensitive channels, and cell walls.
Remove solutes from cytoplasm - (correct Answer) - Inclusion bodies
"relief valve" proteins that form pores that open to release solutes as the
membrane stretches due to influx of water - (correct Answer) - Mechanosensitive
Channels
Prevent membrane from bursting - (correct Answer) - Cell Wall
Water moves out of a cell leading to plasmolysis if not controlled by increasing
compatible solutes - (correct Answer) - Hypertonic Conditions
Water availablity is affected by the interaction of solute molecules or the binding
of water to the surface of the solid. (inversely related to osmotic pressure) -
(correct Answer) - Water Activity
, Microbes adapt to low water activity by being: - (correct Answer) - Osmotolerant
and Halophilic
Able to grow over a wide range of osmotic concentrations - (correct Answer) -
Osmotolerant
Requires high salt concentrations to support growth( possess altered proteins and
membranes to accomodate the high level of salts) - (correct Answer) - Halophilic
A measure of hydrogen ion (H+) activity of a solution - (correct Answer) - pH
pH 0.0 (1.0 MH+) - (correct Answer) - Highly Acidic
pH 14.0 (1 x 10^-14 M H+) - (correct Answer) - Highly Basic
Microbes can be categorized based upon their - (correct Answer) - ph growth range
and pH growth optimum
pH 0 - 5.5 - (correct Answer) - Acidophiles
pH 5.5 - 8.0 - (correct Answer) - Neutrophiles
pH 8.5 to 11.5 - (correct Answer) - Alkalophiles
Most microbes maintain an internal pH near - (correct Answer) - neutrality
The plasma membrane is impermeable to proton. Exchange potassium for protons. -
(correct Answer) - When microbes are near neutrality
Pump protons out of the cell. Some synthesize acid and heat shock proteins that
protect proteins - (correct Answer) - Acidic tolerance response
Many microorganisms change the pH of their habitat by - (correct Answer) -
Producing acidic or basic waste products
The two ways microbial metabolism is affected by temperature - (correct Answer) -
Slowing reactions
Damaging Proteins
Slowing reactions - (correct Answer) - low temperature
Damaging proteins - (correct Answer) - high temperatures
Microbes have cardinal temperatures for - (correct Answer) - Maximal, optimal and
minimal growth
Cardinal Temperatures can be influenced by: - (correct Answer) - Environmental
conditions (pH, available nutrients)
Grow well at 0C, optimally at lower.
- Enzyme systems function very well at low temperatures
- Have high levels of unsaturated fatty acids in their cell membranes, permitting a
semifluid state at low temperatures. - (correct Answer) - Psychrophiles
Grow between 0C - 7C, optimally between 20C and 30C, maximum at 35C - (correct
Answer) - Psychotrophs ( Faculatative Psychrophiles)
Grow between 15C to 20C, optimally 20C-45C, maximum 45 or lower - (correct Answer)
- Mesophiles
Most microbes fall in this category - (correct Answer) - Mesophile
All human pathogens are? Since human body temperature remains steady near 35C -
(correct Answer) - Mesophile
Growth minimum near 45C, optimally between 55C- 65C
- highly heat stable proteins b/c hydrophobic interiors, more noncovalent bonds and
large amounts of non flexible amino acids
-Stabilized by special histone- like proteins
- Membranes contain higher molecular weight lipids that are mmosre saturated and
branch, giving stability - (correct Answer) - Thermophiles
Growth above 90C, growth maximum above 100C, with ranges between 80C and 113C -
(correct Answer) - Hyperthermophiles
Microbes can be categorized according to their usage ( or not) of oxygen - (correct
Answer) - Oxygen Concentration
Microbe able to grow in the presence of O2 - (correct Answer) - Aerobe
Microbe able to grow in the absence of O2 - (correct Answer) - Anaerobe
dependent upon the presence of O2 as the final electron acceptor in respiration.
Superoxide dismutase is present (SOD+)
- Catalase is present (Cat+) - (correct Answer) - Obligate Aerobe
Do not require the presence of O2, but does grow better when it is present (can use
aerobic respiration)
-SOD+
