PENETRATION TESTING FINAL CERTIFICATION
EVALUATION 2026 QUESTIONS WITH
SOLUTIONS GRADED A+
◉ 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.
EVALUATION 2026 QUESTIONS WITH
SOLUTIONS GRADED A+
◉ 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.
