MICR 271 2025 EXAM QUESTIONS AND
CORRECT ANSWERS!!
when recombinant proteins are being produced, misfolding may occur as proper folding
accessories may not be present
how are inclusion bodies formed
microcompartments in the cytoplasm containing enzymes involved in carbon fixation
What are carboxysomes
ribulose bisphosphate carboxylase/oxygenase
what is the predominant enzyme in carbon fixation
extra cytoplasmic membranes that extend and fold within the cytoplasm, increasing surface
area
what is an intracytoplasmic membrane
structural components within the cytoplasm of magnetotactic bacteria that act as miniature
motile compass needles
what are magnetosomes
a resistant asexual spore that develops inside some bacterial cells, allowing for survival in
periods of low nutrient levels and moisture
what is an endospore
start with a normal bacteria cell, asymmetric division results in the mother cell and the
forespore, the forespore is engulfed by the mother cell, the cortex is formed, coat is
synthesized and there is an increase in refractility and heat resistance, endospore is
released due to lysis of mother cell
Summarize the steps of endospore formation
a layer of material attached firmly to an individual bacterium
,what is a capsule
diffuse, unorganized material that is easily removed
What is a slime layer
offer protection by masking the bacteria from immune system and antibiotics during
infection
What do capsules or slime layers do
a structure consisting of polysaccharides surrounding groups of bacteria
what is a biofilm
they harbour bacteria serving as sources of infection for deeper tissues and organs
What problem do biofilms pose for humans
continuous interaction often leads to mutual benefits
Why is an advantage of biofilms
a 2D, crystalline glycoprotein component of the cell envelope that provides protection from
the immune system and phage infection and increases structural stability of the cell wall
What is the S layer
movement in liquid
When are flagella used
when moving on solid surfaces
When are pili used
only when it benefits cell (very tightly regulated gene expression)
When are motility structures made
flagella surround entire periphery of cell
Explain peritrichouse bacteria
, 1 flagella
What is a single/polar cell
have tufts of flagella at one end of a bacterium
What are lophotrichouse cells
a single flagellum at both ends of the bacterium
what is a bipolar cell
the portion attached to the cell wall is called the basal body. It is anchored in the outer
membrane and peptidoglycan by P and L rings. Other rings spin along the central
flagellum.
Describe the structure of a flagellum
very fine hair like appendages
What are pili
at the cell surface via addition of protein subunits for adherence
How, where, and why are pili assembled
the distal tip of the pilus attaches to a surface. The pilus is then rapidly retracted into the
cell and this action moves the cell toward the attachment site
describe the mechanism "twitching" that type 4 pili use
sex
What type of pili allow for the exchange of genetic material via conjugation
very simple, has an S layer outside a cytoplasmic membrane
What is the general cell wall structure of archaea
between the S layer and the cytoplasmic membrane in archaea with similar functions are
peptidoglycan
Where is pseudomurein and what does it do
CORRECT ANSWERS!!
when recombinant proteins are being produced, misfolding may occur as proper folding
accessories may not be present
how are inclusion bodies formed
microcompartments in the cytoplasm containing enzymes involved in carbon fixation
What are carboxysomes
ribulose bisphosphate carboxylase/oxygenase
what is the predominant enzyme in carbon fixation
extra cytoplasmic membranes that extend and fold within the cytoplasm, increasing surface
area
what is an intracytoplasmic membrane
structural components within the cytoplasm of magnetotactic bacteria that act as miniature
motile compass needles
what are magnetosomes
a resistant asexual spore that develops inside some bacterial cells, allowing for survival in
periods of low nutrient levels and moisture
what is an endospore
start with a normal bacteria cell, asymmetric division results in the mother cell and the
forespore, the forespore is engulfed by the mother cell, the cortex is formed, coat is
synthesized and there is an increase in refractility and heat resistance, endospore is
released due to lysis of mother cell
Summarize the steps of endospore formation
a layer of material attached firmly to an individual bacterium
,what is a capsule
diffuse, unorganized material that is easily removed
What is a slime layer
offer protection by masking the bacteria from immune system and antibiotics during
infection
What do capsules or slime layers do
a structure consisting of polysaccharides surrounding groups of bacteria
what is a biofilm
they harbour bacteria serving as sources of infection for deeper tissues and organs
What problem do biofilms pose for humans
continuous interaction often leads to mutual benefits
Why is an advantage of biofilms
a 2D, crystalline glycoprotein component of the cell envelope that provides protection from
the immune system and phage infection and increases structural stability of the cell wall
What is the S layer
movement in liquid
When are flagella used
when moving on solid surfaces
When are pili used
only when it benefits cell (very tightly regulated gene expression)
When are motility structures made
flagella surround entire periphery of cell
Explain peritrichouse bacteria
, 1 flagella
What is a single/polar cell
have tufts of flagella at one end of a bacterium
What are lophotrichouse cells
a single flagellum at both ends of the bacterium
what is a bipolar cell
the portion attached to the cell wall is called the basal body. It is anchored in the outer
membrane and peptidoglycan by P and L rings. Other rings spin along the central
flagellum.
Describe the structure of a flagellum
very fine hair like appendages
What are pili
at the cell surface via addition of protein subunits for adherence
How, where, and why are pili assembled
the distal tip of the pilus attaches to a surface. The pilus is then rapidly retracted into the
cell and this action moves the cell toward the attachment site
describe the mechanism "twitching" that type 4 pili use
sex
What type of pili allow for the exchange of genetic material via conjugation
very simple, has an S layer outside a cytoplasmic membrane
What is the general cell wall structure of archaea
between the S layer and the cytoplasmic membrane in archaea with similar functions are
peptidoglycan
Where is pseudomurein and what does it do
