WGU D311
Microbiology
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,Differentiate Prokaryotic and Eukaryotic Cells
Prokaryotic Cells No true nucleus ( nucleoid region )
Differentiate Prokaryotic and Eukaryotic Cells
Prokaryotic Cells Organelles No membrane - bound organelles Ribosomes Smaller
( 70S )
Differentiate Prokaryotic and Eukaryotic Cells
Prokaryotic Cells Cell Wall Present ( contains peptidoglycan in bacteria )
Differentiate Prokaryotic and Eukaryotic Cells
Eukaryotic Cells Membrane - bound organelles present
Differentiate Prokaryotic and Eukaryotic Cells
Eukaryotic Cells True nucleus enclosed in a membrane
Differentiate Prokaryotic and Eukaryotic Cells
Cell Wall May or may not be present , composition varies
Prokaryotic Cells Examples
Bacteria , Archaea
Eukaryotic Cells Examples
Animals plants , fungi , protists
Bacteria
Found in various environments ; cell walls often contain peptidoglycan .
Archaea
,Found in extreme environments e.g. , hot springs , salt lakes ) ; cell walls lack
peptidoglycan but contain unique lipids .
Bacteria cell walls often contain
peptidoglycan
Archaea cell walls lack
peptidoglycan but contain unique lipids .
Structures Only Found in Eukaryotic Cells
Nucleus Mitochondria Endoplasmic Golgi Apparatus Lysosomes Chloroplasts
Cytoskeleton
Structures Only Found in Prokaryotic Cells
Structures Nucleoid Plasmids Capsule Fimbriae Pili Flagella
Stores DNA and controls cellular activities .
Nucleus
Produces ATP through cellular respiration .
Mitochondria
Synthesizes lipids and proteins .
Endoplasmic Reticulum ( Smooth and Rough
Modifies , sorts , and packages proteins .
Golgi Apparatus
Breaks down waste and cellular debris
Lysosomes
Site of photosynthesis
, Chloroplasts ( in plants and algae
Provides structure and facilitates intracellular transport .
Cytoskeleton ( complex network )
Region where the circular DNA is located , not enclosed by a membrane .
Nucleoid
Small , circular DNA molecules providing additional genetic traits , such as
antibiotic resistance .
Plasmids
A gelatinous outer layer that protects against desiccation and immune attack .
Capsule
Short , hair - like structures for adhesion to surfaces .
Fimbriae
Involved in DNA transfer during conjugation
Pili
Long , whip - like structures for movement
Flagella
Difference Between Gram - Positive and Gram - Negative Cell Walls
Gram - positive Peptidoglycan Layer Thick
Difference Between Gram - Positive and Gram - Negative Cell Walls
Gram - positive Outer Membrane Absent
Difference Between Gram - Positive and Gram - Negative Cell Walls
,Alcohol ( e.g. , beer , wine ) from yeast fermentation . Bread ( leavened by carbon
dioxide from yeast ) . Yogurt , cheese , and kefir from bacterial fermentation .
Fermentation , Industrial Products
Biofuels ( e.g. , ethanol Organic acids ( e.g. , lactic acid , acetic acid ) .
Pharmaceuticals ( e.g. , antibiotics , insulin from recombinant microbes ) .
What Is the Purpose of Bioremediation
To use organisms ( mainly microorganisms ) to remove or neutralize pollutants
from the environment .
Bioremediation How Are Microorganisms Involved
Microbes metabolize toxic substances into less harmful forms .
Bioremediation Microorganisms Role :
Examples Bacteria degrading oil spills ( Pseudomonas species ) . Fungi breaking
down pollutants in soil . Bacteria reducing heavy metal contamination ( e.g. ,
chromium , mercury ) .
A technique that involves introducing , altering , or removing genes within an
individual's cells to treat or prevent disease .
Gene Therapy
Briefly Describe the Method of Gene Therapy
1. Identify Target Gene 2. Vector Selection 3. Gene Insertion 4. Cell Function
Restoration
What Is the Difference Between Synthetic Antimicrobials and Natural
Antibiotics ?
Natural Antibiotics : Produced by microorganisms ( e.g. , penicillin from
Penicillium fungi ) .
,Opportunistic Pathogens Cause disease only in hosts with weakened or
compromised immune systems or when they gain access to normally sterile sites .
Primary Pathogens Example
Mycobacterium tuberculosis ( causes tuberculosis ) .
Opportunistic Pathogens : Example
Candida albicans ( causes infections in immunocompromised individuals ) .
What Are Virulence Factors ?
Molecules , structures , or processes used by pathogens to colonize the host , evade
or suppress the immune system , and cause disease .
Virulence Factors Examples
Toxins ( e.g. , botulinum toxin produced by Clostridium botulinum ) . Enzymes (
e.g. , hyaluronidase that breaks down host tissues ) . Adhesins ( for attachment to
host cells ) . Capsules ( to evade phagocytosis ) . Antigenic variation ( to avoid
immune detection ) .
What Are Adhesins ?
Surface proteins or structures that allow microorganisms to adhere to host cells or
tissues . They are crucial for colonization and establishing infection
Adhesins Examples :
Fimbriae or pili in bacteria ( e.g. , Escherichia coli uses pili to attach to urinary
tract epithelium ) . Adhesin molecules on Plasmodium ( malaria parasite ) to bind
red blood cells .
Pathogens alter their surface antigens to
evade recognition by the host immune system .
Trypanosoma brucei ( causes African sleeping sickness ) frequently changes its
,Deoxyribonuclease ( DNase )
Degrade RNA to disrupt host cellular processes or acquire nutrients .
Ribonucleases ( RNase
Enzymes that hydrolyze phospholipids in host cell membranes , causing cell
lysis and providing nutrients . They also facilitate tissue invasion by breaking
down barriers .
Phospholipases
Phospholipases Example
Phospholipase C : Phospholipase D :
Produced by Clostridium perfringens . Degrades phospholipids in host cell
membranes , leading to cell lysis and tissue necrosis gas gangrene ) .
Phospholipase C
Found in Pseudomonas aeruginosa . Assists in biofilm formation and invasion
of host tissues .
Phospholipase D
Enzymes that hydrolyze peptide bonds in proteins , aiding in tissue
destruction , immune evasion , and nutrient acquisition .
Proteases
Proteases Example
IgA Protease :
Collagenase
Elastase
Produced by Neisseria gonorrhoeae and Streptococcus pneumoniae . Cleaves
IgA antibodies to evade mucosal immunity .
,Zoonotic Disease
A disease that cannot be transmitted from person to person . Example :
Tetanus caused by Clostridium tetani , acquired from the environment .
Noncommunicable Disease
A disease not caused by microorganisms but by other factors such as genetics ,
environmental influences , or lifestyle . Example : Diabetes or atherosclerosis .
Noninfectious Disease
What Is a Portal of Exit ?
The route by which a pathogen leaves the host to infect another host or the
environment . Portals of exit are essential for disease transmission .
Examples of Portals of Exit :
1. Respiratory Tract 2. Gastrointestinal Tract : 3. Genitourinary Tract : 4. Skin : 5.
Blood 6. Other Secretions : Breast milk , tears , or other bodily fluids
Respiratory Tract :
Pathogens exit via sneezing , coughing , or talking . Example : Influenza virus ,
Mycobacterium tuberculosis .
Gastrointestinal Tract :
Pathogens exit via feces , vomit , or saliva . Example : Vibrio cholerae ( cholera ) ,
Norovirus .
Genitourinary Tract :
Pathogens exit via urine , semen , or vaginal secretions . Example : Neisseria
gonorrhoeae ( gonorrhea ) , HIV .
Skin
, HSCs become committed to specific lineages through signals from cytokines
and growth factors ( e.g. , erythropoietin for RBCs , granulocyte colony -
stimulating factor for neutrophils ) .
Lineage Commitment
Progenitor cells mature into functional blood cells . Mature cells are released
into the bloodstream to perform their specific roles
Hematopoiesis Maturation
Erythrocyte
- Transport oxygen ( via hemoglobin ) and carbon dioxide .
Neutrophil
- First responders to bacterial and fungal infections . - Perform phagocytosis of
pathogens .
Eosinophil
- Combat parasitic infections . - Involved in allergic reactions and asthma .
Basophil
-Release histamine and other chemicals during allergic and inflammatory
Mast Cell
- Reside in tissues and release histamine , promoting inflammation and alle
Natural Killer ( NK ) Cells
- Destroy virus - infected and cancerous cells by inducing apoptosis .
Macrophage
- Perform phagocytosis of pathogens and cellular debris . - Present antigens to T
cells to initiate adaptive immunity .
Microbiology
OA EXAM
Definitions, Reviews & Study Guide
Pass the Exam with Confidence
What You Will Get:
➢ OA Definitions,
➢ Concept Reviews
➢ Study Guide
Take and pass the OA :)
, Preview Pages Below
Get the Complete PDF After Purchase
"If you require further clarification or in need of any study resources,
feel free to Message me."
Preview sample only
,Differentiate Prokaryotic and Eukaryotic Cells
Prokaryotic Cells No true nucleus ( nucleoid region )
Differentiate Prokaryotic and Eukaryotic Cells
Prokaryotic Cells Organelles No membrane - bound organelles Ribosomes Smaller
( 70S )
Differentiate Prokaryotic and Eukaryotic Cells
Prokaryotic Cells Cell Wall Present ( contains peptidoglycan in bacteria )
Differentiate Prokaryotic and Eukaryotic Cells
Eukaryotic Cells Membrane - bound organelles present
Differentiate Prokaryotic and Eukaryotic Cells
Eukaryotic Cells True nucleus enclosed in a membrane
Differentiate Prokaryotic and Eukaryotic Cells
Cell Wall May or may not be present , composition varies
Prokaryotic Cells Examples
Bacteria , Archaea
Eukaryotic Cells Examples
Animals plants , fungi , protists
Bacteria
Found in various environments ; cell walls often contain peptidoglycan .
Archaea
,Found in extreme environments e.g. , hot springs , salt lakes ) ; cell walls lack
peptidoglycan but contain unique lipids .
Bacteria cell walls often contain
peptidoglycan
Archaea cell walls lack
peptidoglycan but contain unique lipids .
Structures Only Found in Eukaryotic Cells
Nucleus Mitochondria Endoplasmic Golgi Apparatus Lysosomes Chloroplasts
Cytoskeleton
Structures Only Found in Prokaryotic Cells
Structures Nucleoid Plasmids Capsule Fimbriae Pili Flagella
Stores DNA and controls cellular activities .
Nucleus
Produces ATP through cellular respiration .
Mitochondria
Synthesizes lipids and proteins .
Endoplasmic Reticulum ( Smooth and Rough
Modifies , sorts , and packages proteins .
Golgi Apparatus
Breaks down waste and cellular debris
Lysosomes
Site of photosynthesis
, Chloroplasts ( in plants and algae
Provides structure and facilitates intracellular transport .
Cytoskeleton ( complex network )
Region where the circular DNA is located , not enclosed by a membrane .
Nucleoid
Small , circular DNA molecules providing additional genetic traits , such as
antibiotic resistance .
Plasmids
A gelatinous outer layer that protects against desiccation and immune attack .
Capsule
Short , hair - like structures for adhesion to surfaces .
Fimbriae
Involved in DNA transfer during conjugation
Pili
Long , whip - like structures for movement
Flagella
Difference Between Gram - Positive and Gram - Negative Cell Walls
Gram - positive Peptidoglycan Layer Thick
Difference Between Gram - Positive and Gram - Negative Cell Walls
Gram - positive Outer Membrane Absent
Difference Between Gram - Positive and Gram - Negative Cell Walls
,Alcohol ( e.g. , beer , wine ) from yeast fermentation . Bread ( leavened by carbon
dioxide from yeast ) . Yogurt , cheese , and kefir from bacterial fermentation .
Fermentation , Industrial Products
Biofuels ( e.g. , ethanol Organic acids ( e.g. , lactic acid , acetic acid ) .
Pharmaceuticals ( e.g. , antibiotics , insulin from recombinant microbes ) .
What Is the Purpose of Bioremediation
To use organisms ( mainly microorganisms ) to remove or neutralize pollutants
from the environment .
Bioremediation How Are Microorganisms Involved
Microbes metabolize toxic substances into less harmful forms .
Bioremediation Microorganisms Role :
Examples Bacteria degrading oil spills ( Pseudomonas species ) . Fungi breaking
down pollutants in soil . Bacteria reducing heavy metal contamination ( e.g. ,
chromium , mercury ) .
A technique that involves introducing , altering , or removing genes within an
individual's cells to treat or prevent disease .
Gene Therapy
Briefly Describe the Method of Gene Therapy
1. Identify Target Gene 2. Vector Selection 3. Gene Insertion 4. Cell Function
Restoration
What Is the Difference Between Synthetic Antimicrobials and Natural
Antibiotics ?
Natural Antibiotics : Produced by microorganisms ( e.g. , penicillin from
Penicillium fungi ) .
,Opportunistic Pathogens Cause disease only in hosts with weakened or
compromised immune systems or when they gain access to normally sterile sites .
Primary Pathogens Example
Mycobacterium tuberculosis ( causes tuberculosis ) .
Opportunistic Pathogens : Example
Candida albicans ( causes infections in immunocompromised individuals ) .
What Are Virulence Factors ?
Molecules , structures , or processes used by pathogens to colonize the host , evade
or suppress the immune system , and cause disease .
Virulence Factors Examples
Toxins ( e.g. , botulinum toxin produced by Clostridium botulinum ) . Enzymes (
e.g. , hyaluronidase that breaks down host tissues ) . Adhesins ( for attachment to
host cells ) . Capsules ( to evade phagocytosis ) . Antigenic variation ( to avoid
immune detection ) .
What Are Adhesins ?
Surface proteins or structures that allow microorganisms to adhere to host cells or
tissues . They are crucial for colonization and establishing infection
Adhesins Examples :
Fimbriae or pili in bacteria ( e.g. , Escherichia coli uses pili to attach to urinary
tract epithelium ) . Adhesin molecules on Plasmodium ( malaria parasite ) to bind
red blood cells .
Pathogens alter their surface antigens to
evade recognition by the host immune system .
Trypanosoma brucei ( causes African sleeping sickness ) frequently changes its
,Deoxyribonuclease ( DNase )
Degrade RNA to disrupt host cellular processes or acquire nutrients .
Ribonucleases ( RNase
Enzymes that hydrolyze phospholipids in host cell membranes , causing cell
lysis and providing nutrients . They also facilitate tissue invasion by breaking
down barriers .
Phospholipases
Phospholipases Example
Phospholipase C : Phospholipase D :
Produced by Clostridium perfringens . Degrades phospholipids in host cell
membranes , leading to cell lysis and tissue necrosis gas gangrene ) .
Phospholipase C
Found in Pseudomonas aeruginosa . Assists in biofilm formation and invasion
of host tissues .
Phospholipase D
Enzymes that hydrolyze peptide bonds in proteins , aiding in tissue
destruction , immune evasion , and nutrient acquisition .
Proteases
Proteases Example
IgA Protease :
Collagenase
Elastase
Produced by Neisseria gonorrhoeae and Streptococcus pneumoniae . Cleaves
IgA antibodies to evade mucosal immunity .
,Zoonotic Disease
A disease that cannot be transmitted from person to person . Example :
Tetanus caused by Clostridium tetani , acquired from the environment .
Noncommunicable Disease
A disease not caused by microorganisms but by other factors such as genetics ,
environmental influences , or lifestyle . Example : Diabetes or atherosclerosis .
Noninfectious Disease
What Is a Portal of Exit ?
The route by which a pathogen leaves the host to infect another host or the
environment . Portals of exit are essential for disease transmission .
Examples of Portals of Exit :
1. Respiratory Tract 2. Gastrointestinal Tract : 3. Genitourinary Tract : 4. Skin : 5.
Blood 6. Other Secretions : Breast milk , tears , or other bodily fluids
Respiratory Tract :
Pathogens exit via sneezing , coughing , or talking . Example : Influenza virus ,
Mycobacterium tuberculosis .
Gastrointestinal Tract :
Pathogens exit via feces , vomit , or saliva . Example : Vibrio cholerae ( cholera ) ,
Norovirus .
Genitourinary Tract :
Pathogens exit via urine , semen , or vaginal secretions . Example : Neisseria
gonorrhoeae ( gonorrhea ) , HIV .
Skin
, HSCs become committed to specific lineages through signals from cytokines
and growth factors ( e.g. , erythropoietin for RBCs , granulocyte colony -
stimulating factor for neutrophils ) .
Lineage Commitment
Progenitor cells mature into functional blood cells . Mature cells are released
into the bloodstream to perform their specific roles
Hematopoiesis Maturation
Erythrocyte
- Transport oxygen ( via hemoglobin ) and carbon dioxide .
Neutrophil
- First responders to bacterial and fungal infections . - Perform phagocytosis of
pathogens .
Eosinophil
- Combat parasitic infections . - Involved in allergic reactions and asthma .
Basophil
-Release histamine and other chemicals during allergic and inflammatory
Mast Cell
- Reside in tissues and release histamine , promoting inflammation and alle
Natural Killer ( NK ) Cells
- Destroy virus - infected and cancerous cells by inducing apoptosis .
Macrophage
- Perform phagocytosis of pathogens and cellular debris . - Present antigens to T
cells to initiate adaptive immunity .
