Exam 2: BIOS 242 / BIOS242 Review (Latest 2024/ 2025 Update) Fundamentals of Microbiology with Lab| Questions and Verified Answers| 100% Correct| Grade A- Chamberlain

Exam 2: BIOS 242 / BIOS242 Review (Latest
2024/ 2025 Update) Fundamentals of
Microbiology with Lab| Questions and
Verified Answers| 100% Correct| Grade AChamberlain
Q: what are enzymes?
Answer:
biological catalysts that increase the rate of a chemical reaction
Q: is needed for a reaction to occur
Answer:
activation energy
Q: true or false: enzymes lower the activation energy
Answer:
true
Q: enzymes act on reactant molecules known as
Answer:
substrates
Q: enzymes bind and chemically change substrates into
Answer:
products

Q: what is an apoenzyme?
Answer:
protein, composed of a sequence of amino acids
Q: what is required for a holoenzyme?
Answer:
cofactors and coenzyme
Q: cofactors are elements
Answer:
inorganic
Q: coenzymes are elements
Answer:
organic
Q: what are cofactos?
Answer:
metal ions that activate enzymes
Q: cofactors help bring the and substrate close together
Answer:
active site

Q: true or false: cofactors do not directly participate in chemical reactions with the enzyme
Answer:
false
Q: what the is main function of coenzymes?
Answer:
remove a chemical group from one substrate molecule and add it to a substrate
Q: what is the most important component of coenzymes?
Answer:
vitamins
Q: what are the phases of the growth curve in a bacterial culture?
Answer:
lag phase, exponential growth/log phase, stationary growth phase, death phase
Q: what is the lag phase?
Answer:
flat period on the graph when the population appears to not be growing
Q: what are the reason growth lags?
Answer:
1.newly inoculated cells require a period of adjustment, enlargement, and synthesis
2.the cells are not multiplying at max rate
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Auto troph “””self-feeder”” inorganic CO2 as its carbon source and convert into carbon compounds”
heterotroph must obtain its carbon in organic form, dependent on other life forms
Phototroph Photosynthesis
Chemotroph Chemical reaction
Saprobes “””Recycling””, release enzymes into environment to digest food into smaller particles that can be transported. Dead organisms, decomposer’s release exoenzyme”
Diffusion Movement of molecules from high to low concentration
Osmosis movement of water from high to low concentration
Psychrophiles Below 15 degrees CelsiusEx: refrigerator
Mesophile Pathogens 30-40 degrees Celsius
Thermophile 40-60 degrees Celsius
Thermophile Soil & water associated with volcanic activity, compost piles
Extreme thermophile Grow between 80-121 degrees Celsius
Psychrotroph 5-35 degrees Celsius
Capnophile grow at high CO2 content in atmosphere
Acidophile Require acidic environment for growth (below 7 pH)Ex: mold & yeast
Alkalinophiles Hot pools & soils that contain high levels of minerals
Halophile Salt for growth Ex: dead sea
Barophile Bottom of ocean up to 1000x atmospheric pressure
Binary Fission – Parent cell enlarge- Chromosome Duplicate- Cell envelope pulls together in center of cell to form a septum- Cell divides into 2 daughter cells
Generation/Doubling Time Time required for complete fission cycle
Stages of Normal Growth Curve Lag Phase, Exponential Growth (log phase), Stationary growth phase, death phase
Lag Phase require period of adjustment, enlargement & synthesis; not yet multiplying
Exponential Growth (Log Phase) Growth curve increases geometrically; antibiotics are most effective
Stationary Growth Phase Cells stop growing or grow slowlyRate of growth = rate of death
Death Phase Cells die at exponential rate because no nutrients are present
Aerobe gaseous O2 in metabolism, intermediate enzymes
Obligate aerobe cannot grow without O2
Facultative anaerobe Does not require O2, can grow without O2
Anaerobe Strict or obligate anaerobe, cannot tolerate free O2 & will die in its presence, no enzymes
True or False: Bacteria is a replicating cell and is done through binary fission. True
Heat Kill off bacteria
Cold Slow growth, depends on optimal growth temperature. Psychrophiles grow faster in this condition, while mesophile and thermophiles grow slow
Acid Can’t survive on skin if it’s unable to handle the acidity
Cardinal Temperature Range of temperature for growth
Minimum Temperature Lowest temperature, organisms NOT killed, just stop growing
Maximum temperature Highest Temperature
Optimum temperature intermediate temperature, best one!
Anabolism Requires energy (ATP) input, synthesis of cell molecule & structure
Catabolism Release energy (ATP), break bonds of larger molecule
Enzymes Lower activation energy
Substrate Enzyme acts on
Catalyst Speed up rate of chemical reaction
Cofactor nonprotein portion; organic or inorganicEx: minerals
Coenzyme organic cofactor work with the apoenzyme to alter substrateEx: vitamins
Apoenzyme Actual site where substrate binds, 3 dimensional crevice
Oxidoreductases Transfer electrons from one substrate to another
Transferases Transfer functional group from one substrate to another
Hydrolases Cleave bonds on molecules with addition of H2O
Lyases Add groups or remove from double bounded substrate
Isomerases Change a substrate to its isomeric form
Ligases Catalyze formation of bonds with input of ATP & removal of H2O
Exoenzyme transport extracellularly
Endoenzyme Retained intracellularly & function there
Competitive inhibition Occupy active site, preventing substrate from binding because it wants to bind to the same active site
Noncompetitive inhibition Binds outside active site & changes the shape. Provides negative feedback
Competitive Inhibition Process Substrate that doesn’t belong binds to active site and prevents any products from being made
Noncompetitive Inhibition Process Substrate binds to active site to make product and is released. It then binds to the regulatory site changing the shape enabling the substrate to bind and no products can be made.
Aerobic Respiration GlycolysisKrebs Cycle (NADH + FADH2)ETC: H2O is produced by O2Large ATP generatedCO2 made (36-38)
Anaerobic Respiration Utilizes glycolysisKrebs Cycle (NADH + FADH2)ETC: final electron acceptorCO2 made (36-38)
Fermentation Only glycolysisNo Krebs CycleNO ATPNAD+ produced from ATP in glycolysisCO2 made (2)
Krebs Cyle – Connects all metabolic pathways- Most reduced forms NADH3 + FADH2- Drives ATP
Inner mitochondrial membrane Electron transport in eukaryotic cells occurs where?
Cell membrane Electron transport in bacterial cells occur where?
Outside body inanimate objects SterilizationDisinfectionDecontamination
Living surfaces Antisepsis/degermationAsepsisSepsis
Sterilization Destruction of all microbial life including endosporesEx: Steam autoclave, syring, surgical equipment
Disinfection Destroy microbial life, reducing contamination on inanimate surfacesEx: destroy vegetative pathogens
Decontamination/Sanitization Destroy microbial life using soap or detergent to reduce contamination
Antisepsis/Degermation Application/scrubbing chemical agents
Asepsis Chemical agents exposed directly on body surface to destroy or inhibit vegetative pathogen
Sepsis Growth of microorganism in blood and tissue
Bacterial Endospore Most resistant microbial entity
Cidal Chemical agents that kill microorganism
Static Microbes prevented from multiplying but are NOT killed
Pasteurization Heat is applied to liquids to kill potential agents of infection and spoilage while retaining liquid’s flavor and food value.
Halogens Group 7 elementsEx: Tincture (alcohol mixture used in hospital)
Antibiotics Substances produced by natural metabolic process of some microorganisms
Selective Toxicity Antimicrobial drugs should kill or inhibit microbial cells without damaging the host tissues
As the characteristics of infectious agent become to that of host, selective toxicity becomes to achieve & undesirable side effects are more likely to occur More Similar; More difficult
Antimicrobial Drug that inhibits Protein Synthesis ClindamycinErythromycin
Antimicrobial Drug that inhibits Folic Acid Synthesis SulfonamidesTrimethoprim
Antimicrobial Drug that inhibits Cell wall PenicillinVancomycin
Antimicrobial Drug that inhibits Cell membrane PolymyxinsDaptomycin
Antimicrobial Drug that inhibits DNA/RNA QuinolonesRifampin
Broad spectrum Effective against wide variety of microbial typesEx: Tetracycline
Narrow Spectrum Effective against limited array of microbial typesEx: Isoniazid –> specific for Mycobacteria Tuberculosis
Drugs ending in -illin Attack the cell wall, specifically the Beta lactic ring
Cellular basis of Drug Resistance 1. Enzymes synthesze, inactivate drug2. Prevention of drug entry3. Drug eliminated, efflux of drugs4. Binding sites/receptros altered5. Affect metabolic pathway shutdown or alternate pathway (persister cells)6. Spontaneous chromosome mutation & horizontal gene transfer
Persister cells If antibiotics are not taken in its entirety, these cells will come back around
Broad spectrum – Treats infection- Destroy good biota
Normal Flora begins when? Starts at birth
Ways for Fetus to gain Normal Flora Vaginal canal during birthBreast milkBottle feedingSkin contact (staff, parents, grandparents)
Level 4 Most virulent biosafety level
TORCH acronym ToxoplasmosisOther diseasesRubellaCytomegalovirusHerpes Simplex Virus
TORCH Common infections of fetus and neonate
Endotoxin LPS of outer membrane,Not actively secreted,Shed from outer membrane,ONLY gram-negative bacteriaEx: fever, septic shock
Exotoxin Secreted by a living bacterial cell to the infected tissueEx: lung, heart, kidney
Localized infection Enter’s body and remains confined to a specific tissueEx: warts, boils, fungal skin infections
Systemic infection Infection in the blood and all throughout the body nerves
Focal infection agnate breaks loose from a local infection and carried to other tissue
Mixed infection More than 1 bacteria causing a diseaseEx: wound infection, dental caries, human bite infection
Primary infection Initial infection
Secondary infection when primary infection complicated by another infection
Sign Objective measurement that can be seen with the naked eye
Symptom Subjective measurement about what patient says
Asymptomatic Infections that go unnoticed
Latency a dormant state of an infectious agentEx: chickenpox to shingles
Stages of an Infection 1. Incubation Period2. Prodromal Stage3. Period of invasion4. Convalescent
Incubation Period Time from initial contact to appearance of symptoms
Prodromal stage “notable symptoms start “”feel like I’m coming down with something”””
Period of invasion infectious agent multiplying at high levels, greatest virulence
Convalescent Symptoms decline, recovery
Reservoir Primary habitat in natural world from which a pathogen originates
Living Reservoirs Human CarrierZoonotic animalsVectors/arthropodsNonliving/inanimate
Vector Live animal that transmits infectious agent from one host to another
Biological vector Participates in pathogen’s life cycleEx: Chicken, bat
Mechanical vector Transport pathogen without being infected, no life cycleEx: cockroach, flies
Fomite Inanimate object that harbor and transmits pathogens, nonliving reservoir
Endemic # of cases over long period of time is steady on [articular geographic locale
Epidemic Greater frequency of disease than normal for population area
Sporadic Disease Occasional cases reported at irregular interval in random locales
Pandemic Spread of an epidemic across continents