WGU D311 MICROBIOLOGY 2026 STUDY GUIDE QUESTIONS
AND ANSWERS MARKED A+
✔✔Characteristics of platyhelminthes (flukes/tapeworms) - ✔✔Flukes: nonsegmented
flatworms that have oral sucker, attach to inner walls of intestines, lungs, large blood
vessels or the liver
Tapeworms:
segmented flatworms that may have suckers at the head region, attach to wall of small
intestine
✔✔homolactic fermentation - ✔✔produces lactic acid only
✔✔heterolactic fermentation - ✔✔Mixture of lactic acid, ethanol and co2
✔✔acetone-butanol-ethanol fermentation - ✔✔industrial solvents. Kills clostridium
acetobutylicum
✔✔alcholic fermentation - ✔✔Microbes: Candida, Saccharomyces
commercial: beer and bread
✔✔butanediol fermentation - ✔✔Microbes: Klebsiella, Enterobacter,
Commerical: Chardonnay wine
✔✔butyric acid - ✔✔Microbes: clostridium butyricum
Commerical: butter
✔✔lactic acid fermentation - ✔✔Microbes: strep, lactobacillis,
commerical: yogurt, cheese and sauerkraut
✔✔mixed acid fermentation - ✔✔Microbes: esherichia, shigella
commerical: vinegar, cosmetics, pharmaceuticals
✔✔Proprionic acid - ✔✔Microbes: propionibacterium, Bifidobacterium
commercial: Swiss cheese
✔✔Purpose of bioremediation - ✔✔Stimulate microorganisms with nutrients and other
chemicals that will enable them to destroy contaminants.
✔✔Xenobiotics - ✔✔Things that humans pollute the air with and are more than what
naturally happen. Bacteria that helps with this is Rhodococcus and Pseudomonas
degrade contaminants found in oil and co2
✔✔gene therapy - ✔✔the transplantation of normal genes into cells in place of missing
or defective ones in order to correct genetic disorders.
, ✔✔What does gene therapy use - ✔✔viruses bc it has the ability to deliver genetic
material into the cells
✔✔risks of gene therapy - ✔✔Inflammation: lead to organ failure
Toxicity: virus can change to be infect
Cancer: disrupt normal cell cycling and cause tumor formation
✔✔synthetic antimicrobials - ✔✔manufactured by chemical processes not found in
nature
ex: sulfanilamide, which led to production of Quinolones and Oxazidinones
✔✔natural antibiotics - ✔✔Produced by microbes in nature
ex: PCN in mold to treat streptococcus, meningococcal
✔✔semisynthetic antimicrobials - ✔✔chemical modification of naturally occurring
antibiotics. This allows for more bacteria to be targeted, increase stability and decrease
toxicity
✔✔Pathogenicity - ✔✔ability to cause disease
✔✔Virulence - ✔✔severity of disease
✔✔median infectious dose (ID50) - ✔✔the number of pathogenic cells/viruses needed
to cause infection in 50% of inoculated animals
✔✔median lethal dose (LD50) - ✔✔The number of pathogenic cells/viruses/toxins
needed to kill 50% of infection animals
✔✔Primary pathogen - ✔✔causes disease in healthy host
✔✔opportunistic pathogens - ✔✔cause disease in immunocomprised individuals
✔✔What is positive about bacteria - ✔✔Bacteria are everywhere
skin: beneficial, keeps harmful bacteria from growing
digestive system: break down food and absorb vitamins
ecosystem: decompose, fix nitrogen that plants need
✔✔virulence factors - ✔✔traits used to invade and establish themselves in the host,
also determine the degree of tissue damage that occurs - severity of disease
✔✔Streptococcus pyogenes - ✔✔strep throat- protein F- resp epithelial cells
✔✔Streptococcus mutans - ✔✔dental caries- adhesion P1- teeth
AND ANSWERS MARKED A+
✔✔Characteristics of platyhelminthes (flukes/tapeworms) - ✔✔Flukes: nonsegmented
flatworms that have oral sucker, attach to inner walls of intestines, lungs, large blood
vessels or the liver
Tapeworms:
segmented flatworms that may have suckers at the head region, attach to wall of small
intestine
✔✔homolactic fermentation - ✔✔produces lactic acid only
✔✔heterolactic fermentation - ✔✔Mixture of lactic acid, ethanol and co2
✔✔acetone-butanol-ethanol fermentation - ✔✔industrial solvents. Kills clostridium
acetobutylicum
✔✔alcholic fermentation - ✔✔Microbes: Candida, Saccharomyces
commercial: beer and bread
✔✔butanediol fermentation - ✔✔Microbes: Klebsiella, Enterobacter,
Commerical: Chardonnay wine
✔✔butyric acid - ✔✔Microbes: clostridium butyricum
Commerical: butter
✔✔lactic acid fermentation - ✔✔Microbes: strep, lactobacillis,
commerical: yogurt, cheese and sauerkraut
✔✔mixed acid fermentation - ✔✔Microbes: esherichia, shigella
commerical: vinegar, cosmetics, pharmaceuticals
✔✔Proprionic acid - ✔✔Microbes: propionibacterium, Bifidobacterium
commercial: Swiss cheese
✔✔Purpose of bioremediation - ✔✔Stimulate microorganisms with nutrients and other
chemicals that will enable them to destroy contaminants.
✔✔Xenobiotics - ✔✔Things that humans pollute the air with and are more than what
naturally happen. Bacteria that helps with this is Rhodococcus and Pseudomonas
degrade contaminants found in oil and co2
✔✔gene therapy - ✔✔the transplantation of normal genes into cells in place of missing
or defective ones in order to correct genetic disorders.
, ✔✔What does gene therapy use - ✔✔viruses bc it has the ability to deliver genetic
material into the cells
✔✔risks of gene therapy - ✔✔Inflammation: lead to organ failure
Toxicity: virus can change to be infect
Cancer: disrupt normal cell cycling and cause tumor formation
✔✔synthetic antimicrobials - ✔✔manufactured by chemical processes not found in
nature
ex: sulfanilamide, which led to production of Quinolones and Oxazidinones
✔✔natural antibiotics - ✔✔Produced by microbes in nature
ex: PCN in mold to treat streptococcus, meningococcal
✔✔semisynthetic antimicrobials - ✔✔chemical modification of naturally occurring
antibiotics. This allows for more bacteria to be targeted, increase stability and decrease
toxicity
✔✔Pathogenicity - ✔✔ability to cause disease
✔✔Virulence - ✔✔severity of disease
✔✔median infectious dose (ID50) - ✔✔the number of pathogenic cells/viruses needed
to cause infection in 50% of inoculated animals
✔✔median lethal dose (LD50) - ✔✔The number of pathogenic cells/viruses/toxins
needed to kill 50% of infection animals
✔✔Primary pathogen - ✔✔causes disease in healthy host
✔✔opportunistic pathogens - ✔✔cause disease in immunocomprised individuals
✔✔What is positive about bacteria - ✔✔Bacteria are everywhere
skin: beneficial, keeps harmful bacteria from growing
digestive system: break down food and absorb vitamins
ecosystem: decompose, fix nitrogen that plants need
✔✔virulence factors - ✔✔traits used to invade and establish themselves in the host,
also determine the degree of tissue damage that occurs - severity of disease
✔✔Streptococcus pyogenes - ✔✔strep throat- protein F- resp epithelial cells
✔✔Streptococcus mutans - ✔✔dental caries- adhesion P1- teeth
