NURS 350 Exam 2 Questions and
Answers 100% Solved | Graded A+
1. Identify mechanisms used by pathogens to survive defenses of the body.
- ✔✔o Infectious disease: infection spread from person to person
o Pathogens successfully cause disease because they"
Compete with normal flora
Produce toxins
Produce enzymes to
• Avoid phagocytosis, opsonization, destroy connective tissues
Avoid lysis
• Stop complement cascade by degrading C3b
Paralyze ciliary activity
2. Describe the different factors for infection. - ✔✔o Communicability
Ability to spread disease from one to others
o Infectivity
Ability of pathogen to invade and multiply in host
o Virulence
1
©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.
,Capacity of pathogen to cause severe disease
o Pathogenicity
Ability of an agent to produce diseae
o Portal of entry
Route by which pathogenic microorganism infects host
o Toxigenicity
Ability to produce soluble toxins or endotoxins, factors that influence
pathogen's virulence
3. Understand the significance of bacterial toxins. - ✔✔o Toxin production
Exotoxins (released from living microbes)
• Enzymes that damage host cell plasma membranes or can inactivate
enzymes critical to protein synthesis
Endotoxins (released from lysed gram-negative bacteria: LPS)
• Activate inflammatory response and produce fever
4. Explain bacteremia or septicemia. - ✔✔o Bacteremia (presence) or
septicemia (growth)
Bacteria present in blood
Failure of the body's defense mechanisms
Caused by gram-negative bacteria
Endotoxins released in blood activate complement and clotting systems
2
©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.
,• Capillary permeability causes plasma to escape into surrounding tissues
producing widespread hypotension; severe cases= cardiovascular shock
Gram negative has LPS and thinner peptidoglycan
Gram positive has thicker peptidoglycan
5. Using HIV as an example, explain how viruses infect cells (be able to
describe event steps and key players and what occurs). - ✔✔• Human
Immunodeficiency Virus (HIV)
o Structure
Gp120 proteing binds to the CD4 molecule found primarily on surface of
helper T cells
• Destroys CD4 Th cells
o Reverses CD4: CD8 ratio
o Coreceptors
CXCR4 and CCR5
• Strains can be selective for these receptors; influence the tropism of the
target cells
Steps of how HIV infects cells:
1. virion binds to CD 4 and chemokine receptors
3
©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.
, 2.fusion of HIV membrane with host cell membrane entry of viral genome
into cytoplasm and gp41 enters cells
-RNA-> DNA
3. integration of provirus into host cell genome
-DNA->mRNA
4.Cytokine activation of cell; transcription of HIV genome; transport of viral
RNAs to cytoplasm
-protease trim virions
5. synthesis of HIV proteins; assembly of virion core
6. Budding and release of mature virion
7. New HIV virion
6. Identify the key immunologic finding in those with HIV infection/AIDS. -
✔✔Th cells < 200 cells/mm^3 diagnositc for AIDS
CD4 T Cells (normal= 800-1000/mm^3) declines to <400/mm^3
8. Identify opportunistic infections and malignancies associated with AIDS.
- ✔✔-herpes
-varicella
-mycobacterium (Tb)
-fungi
-pneumocystis
4
©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.
Answers 100% Solved | Graded A+
1. Identify mechanisms used by pathogens to survive defenses of the body.
- ✔✔o Infectious disease: infection spread from person to person
o Pathogens successfully cause disease because they"
Compete with normal flora
Produce toxins
Produce enzymes to
• Avoid phagocytosis, opsonization, destroy connective tissues
Avoid lysis
• Stop complement cascade by degrading C3b
Paralyze ciliary activity
2. Describe the different factors for infection. - ✔✔o Communicability
Ability to spread disease from one to others
o Infectivity
Ability of pathogen to invade and multiply in host
o Virulence
1
©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.
,Capacity of pathogen to cause severe disease
o Pathogenicity
Ability of an agent to produce diseae
o Portal of entry
Route by which pathogenic microorganism infects host
o Toxigenicity
Ability to produce soluble toxins or endotoxins, factors that influence
pathogen's virulence
3. Understand the significance of bacterial toxins. - ✔✔o Toxin production
Exotoxins (released from living microbes)
• Enzymes that damage host cell plasma membranes or can inactivate
enzymes critical to protein synthesis
Endotoxins (released from lysed gram-negative bacteria: LPS)
• Activate inflammatory response and produce fever
4. Explain bacteremia or septicemia. - ✔✔o Bacteremia (presence) or
septicemia (growth)
Bacteria present in blood
Failure of the body's defense mechanisms
Caused by gram-negative bacteria
Endotoxins released in blood activate complement and clotting systems
2
©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.
,• Capillary permeability causes plasma to escape into surrounding tissues
producing widespread hypotension; severe cases= cardiovascular shock
Gram negative has LPS and thinner peptidoglycan
Gram positive has thicker peptidoglycan
5. Using HIV as an example, explain how viruses infect cells (be able to
describe event steps and key players and what occurs). - ✔✔• Human
Immunodeficiency Virus (HIV)
o Structure
Gp120 proteing binds to the CD4 molecule found primarily on surface of
helper T cells
• Destroys CD4 Th cells
o Reverses CD4: CD8 ratio
o Coreceptors
CXCR4 and CCR5
• Strains can be selective for these receptors; influence the tropism of the
target cells
Steps of how HIV infects cells:
1. virion binds to CD 4 and chemokine receptors
3
©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.
, 2.fusion of HIV membrane with host cell membrane entry of viral genome
into cytoplasm and gp41 enters cells
-RNA-> DNA
3. integration of provirus into host cell genome
-DNA->mRNA
4.Cytokine activation of cell; transcription of HIV genome; transport of viral
RNAs to cytoplasm
-protease trim virions
5. synthesis of HIV proteins; assembly of virion core
6. Budding and release of mature virion
7. New HIV virion
6. Identify the key immunologic finding in those with HIV infection/AIDS. -
✔✔Th cells < 200 cells/mm^3 diagnositc for AIDS
CD4 T Cells (normal= 800-1000/mm^3) declines to <400/mm^3
8. Identify opportunistic infections and malignancies associated with AIDS.
- ✔✔-herpes
-varicella
-mycobacterium (Tb)
-fungi
-pneumocystis
4
©JOSHCLAY 2024/2025. YEAR PUBLISHED 2024.
