NEWEST WGU C453 OA MICROBIOLOGY EXAM /
MICROBIOLOGY C453 OA EXAM LATEST UPDATED
VERSION COMPLETE ACTUAL TEST QUESTIONS AND
CORRECT DETAILED ANSWER (100% CORRECT VERIFIED
SOLUTIONS) |ALREADY GRADED A+ (BRAND NEW!!)
Bacteria - ANSWER: Single-celled organism that do not have a cell nucleus and the
membrane-enclosed intracellular structures found in most other cells (Prokaryotic
cell).
Gram-positive Bacteria - ANSWER: Thick layer of peptidoglycan (20-80nm across).
The peptidoglycan layer is closely attached to the outer surface of the cell
membrane. Retains crystal violet stains. Lack an outer membrane and a periplasmic
space.
Gram-negative Bacteria - ANSWER: Cell wall is thinner, but more complex. Only 10-
20% peptidoglycan. Contains an outer membrane, leaving a very narrow periplasmic
space. Does not retain crystal violet stain because of large quantities of lipoproteins
and lipopolysaccharides (endotoxin).
Acid-fast Bacteria - ANSWER: Cell wall is thick, but consists of 60% lipids. Lipids make
acid-fast organisms impermeable to most other stains and protect them from acids
and alkalis. Stain as gram-positive. Grow slowly because the lipids impeded entry of
nutrients.
Endotoxin - ANSWER: Lipopolysaccharide (LPS). Part of the outer membrane of the
cell wall of gram-negative bacteria. It can cause fever and dilates blood vessels-
causing BP to drop. Bacteria typically release this when they are dying, so killing
them increases the concentration of this toxic substance. Antibiotics given late in the
infection can cause worsening of symptoms or even death.
Wall-deficient Bacteria - ANSWER: Protected by a strengthened cell membrane that
contains sterols. Example: mycobacterium paratuberculosis with Crohn's disease- a
chronic disorder of the intestine.
Coccus - ANSWER: Sphere shaped bacteria
Coccobacillus - ANSWER: Short rod shaped bacteria (between cocci and bacilli)
Vibrio - ANSWER: Comma shaped bacteria
Bacillus - ANSWER: Rod shaped bacteria
Spirillum - ANSWER: Rigid, wavy shaped bacteria
, Spirochete - ANSWER: Corkscrew shape bacteria
Function of cell membrane - ANSWER: To regulate movement of materials into and
out of the cell by transport mechanisms. It synthesizes cell wall components, assists
with DNA replication, secretes proteins, carries on respiration, and captures energy
as ATP.
Function of the cell wall - ANSWER: Helps maintain the characteristic shape of the
cell and prevents the cell from bursting when fluids flow into the cell by osmosis. Lies
outside the cell membrane.
Peptidoglycan - ANSWER: Single most important component of the bacterial cell
wall.
Capsule - ANSWER: Discrete layer of polysaccharides that protects the cell. Promotes
infection by protecting the bacterial cell from engulfment by predatory protozoa or
WBC (phagocytes). Also mediates adherence of cells to surfaces.
Pili - ANSWER: Tiny, hallow projections that are used to attach bacteria to surfaces.
Are NOT involved in movement. Promote infection by transferring DNA amount
bacteria- which in turn can transfer antibiotic resistance. Can adhere to RBC and
cause blood cells to clump.
Flagella - ANSWER: Long, thin, helical appendages that allow bacteria to move.
Endospore - ANSWER: Helps the organism survive, and is not a means of
reproduction. They are formed within the cells, contain very little water and are
highly resistant to heat, drying, acids, bases, certain disinfectants, and even
radiation. They are capable of surviving adverse environmental conditions for long
periods of time.
Chemotaxis - ANSWER: Process of bacteria moving toward or away from substances
in their environment. Towards- positive, Away- Negative.
Bacteria that produce spores - ANSWER: Bacillus, Clostridium
Helminths - ANSWER: Worm-like organisms living in and feeding on live hosts,
receiving nourishment and protection while disrupting their hosts' nutrient
absorption, causing weakness and disease. Example: Flukes, tapeworms, adult
round-worms of intestine, and roundworm larvae.
Zygomycota - ANSWER: Bread molds
Ascomycota - ANSWER: Sac fungi. Yeasts. Replication by sexual reproduction.
Basidiomycota - ANSWER: Club fungi. Amanita and other mushrooms.
MICROBIOLOGY C453 OA EXAM LATEST UPDATED
VERSION COMPLETE ACTUAL TEST QUESTIONS AND
CORRECT DETAILED ANSWER (100% CORRECT VERIFIED
SOLUTIONS) |ALREADY GRADED A+ (BRAND NEW!!)
Bacteria - ANSWER: Single-celled organism that do not have a cell nucleus and the
membrane-enclosed intracellular structures found in most other cells (Prokaryotic
cell).
Gram-positive Bacteria - ANSWER: Thick layer of peptidoglycan (20-80nm across).
The peptidoglycan layer is closely attached to the outer surface of the cell
membrane. Retains crystal violet stains. Lack an outer membrane and a periplasmic
space.
Gram-negative Bacteria - ANSWER: Cell wall is thinner, but more complex. Only 10-
20% peptidoglycan. Contains an outer membrane, leaving a very narrow periplasmic
space. Does not retain crystal violet stain because of large quantities of lipoproteins
and lipopolysaccharides (endotoxin).
Acid-fast Bacteria - ANSWER: Cell wall is thick, but consists of 60% lipids. Lipids make
acid-fast organisms impermeable to most other stains and protect them from acids
and alkalis. Stain as gram-positive. Grow slowly because the lipids impeded entry of
nutrients.
Endotoxin - ANSWER: Lipopolysaccharide (LPS). Part of the outer membrane of the
cell wall of gram-negative bacteria. It can cause fever and dilates blood vessels-
causing BP to drop. Bacteria typically release this when they are dying, so killing
them increases the concentration of this toxic substance. Antibiotics given late in the
infection can cause worsening of symptoms or even death.
Wall-deficient Bacteria - ANSWER: Protected by a strengthened cell membrane that
contains sterols. Example: mycobacterium paratuberculosis with Crohn's disease- a
chronic disorder of the intestine.
Coccus - ANSWER: Sphere shaped bacteria
Coccobacillus - ANSWER: Short rod shaped bacteria (between cocci and bacilli)
Vibrio - ANSWER: Comma shaped bacteria
Bacillus - ANSWER: Rod shaped bacteria
Spirillum - ANSWER: Rigid, wavy shaped bacteria
, Spirochete - ANSWER: Corkscrew shape bacteria
Function of cell membrane - ANSWER: To regulate movement of materials into and
out of the cell by transport mechanisms. It synthesizes cell wall components, assists
with DNA replication, secretes proteins, carries on respiration, and captures energy
as ATP.
Function of the cell wall - ANSWER: Helps maintain the characteristic shape of the
cell and prevents the cell from bursting when fluids flow into the cell by osmosis. Lies
outside the cell membrane.
Peptidoglycan - ANSWER: Single most important component of the bacterial cell
wall.
Capsule - ANSWER: Discrete layer of polysaccharides that protects the cell. Promotes
infection by protecting the bacterial cell from engulfment by predatory protozoa or
WBC (phagocytes). Also mediates adherence of cells to surfaces.
Pili - ANSWER: Tiny, hallow projections that are used to attach bacteria to surfaces.
Are NOT involved in movement. Promote infection by transferring DNA amount
bacteria- which in turn can transfer antibiotic resistance. Can adhere to RBC and
cause blood cells to clump.
Flagella - ANSWER: Long, thin, helical appendages that allow bacteria to move.
Endospore - ANSWER: Helps the organism survive, and is not a means of
reproduction. They are formed within the cells, contain very little water and are
highly resistant to heat, drying, acids, bases, certain disinfectants, and even
radiation. They are capable of surviving adverse environmental conditions for long
periods of time.
Chemotaxis - ANSWER: Process of bacteria moving toward or away from substances
in their environment. Towards- positive, Away- Negative.
Bacteria that produce spores - ANSWER: Bacillus, Clostridium
Helminths - ANSWER: Worm-like organisms living in and feeding on live hosts,
receiving nourishment and protection while disrupting their hosts' nutrient
absorption, causing weakness and disease. Example: Flukes, tapeworms, adult
round-worms of intestine, and roundworm larvae.
Zygomycota - ANSWER: Bread molds
Ascomycota - ANSWER: Sac fungi. Yeasts. Replication by sexual reproduction.
Basidiomycota - ANSWER: Club fungi. Amanita and other mushrooms.
