Microbes In Human Health And Disease (MODULE 2A/2B) Flashcards
T or F
Viruses prions are referred to as A - cellular
T
T or F
Within the scope of medical microbiology chart: Etiologic Agents of Infectious Diseases is broken down into Cellular (Eukaryotes and Prokaryotes) and A - Cellular (Viruses, Viroids, and prions)
*Look at chart on slide 7 for reference
T
Prokaryotes vs. Eukaryotes
Prokaryotes: single - cell organisms, no real nucleus, no membrane-bound organelles, unique cell wall (bacteria)
Eukaryotes: real nucleus, membrane-bound organelles; some have cells lack walls (plants, fungi), some do not (animals)
- Protozoa: single-cell organisms similar to animal cells, belong to ‘parasites’
- Fungi: can be single- or multicellular, unique cell wall
- Helminths: multicellular, belong to animals, cells have no cell wall, most closely related to humans, belong to ‘parasites’
T or F
Fungi can only be single celled
F
Fungi can be single- or multicellular, unique cell wall
T or F
Prions are misfolded protiens
T
What are Viroids?
RNA molecule (so far only know to cause diseases in plants)
T or F
Viruses: RNA or DNA surrounded by a structural protein layer, many with additional structural features; no metabolic capability
T
Compare and contrast prokaryotic cells and eukaryotic cells.
Prokaryotic cells - small, simple (0.1-5mm); unicellular; No nucleus; Circular DNA; No membrane-bound organelles
Eukaryotic cells - Large, complex (10-100mm); Uni- or multicellular; Nucleus present; Linear DNA; Membrane-bound organelles present
BOTH: Cytoplasm; DNA and RNA; Ribosomes
T or F
Bacteria can synthesize cholesterol
F
T or F
Prokaryotic cells have a higher protein content
T
What is the major component of the prokaryotic cells wall?
Peptidoglycan (protection from osmotic pressure)
T or F
Gram-positive bacteria have less peptidoglycan than gram-negative bacteria.
F
Gram-positive bacteria has more peptidoglycan than gram-negative bacteria
What is the role of lipopolysaccharide (LPS) in the gram-negative bacteria of the cell wall of prokaryotic cells?
A substance that can lead to our immune system reacting to them, because it acts as an antigen and leading to an up regulation of the immune response.
T or F
Gram-positive has a high susceptibility to penicillin, and gram-negative has a low susceptibility to penicillin
T
T or F
Gram-positive has high susceptibility to lysozyme, and gram-negative has low
T
Gram-positive has _____ susceptibility to lysis by complement and gram-negative has _____.
Low
High
T or F
Exotoxin are present in some species of gram-positive bacteria and a few species of gram-negative bacteria
T
What is the wax like substance that covers gram-positive bacteria?
Mycolic acid
Name the four identifications of flagella.
Monotrichous - one strand
Amphitrichous - two strands
Lophotrichous - three strands
Peritrichous - multiple strands
Name the sticky, bristle-like appendages structure that has a purpose for biofilm formation.
Fimbriae
What is the purpose of Pili?
Hollow tubes (made of proteins), make a connection between two cells
Purpose: transfer of DNA between two cells (conjugation)
What are endospores and why are they clinically important?
Found in some gram-positive genera of bacteria
Clinically important: certain species of Bacillus and Clostridium
Resistant to commonly used methods of sterilisation (difficult to get rid of)
*Cells can toggle back between an endospores stage and a vegetative stage
Vegetative Cells vs Endospores
Vegetative cells - sensitive to extreme temperatures and radiation; gram-positive; physiological water content and enzymatic activity; capable for growth and metabolism
Endospores - resistant to extreme temperatures and radiation; do not absorb gram stain; need special endospore stains; dehydrated; no metabolic activity; dormant; no growth or metabolic activity
Explain fermentation
Pyruvate ——> Glucose
*when glucose is broken down to pyrucate for the purpose of ATP production, and NAD+ is necessary for glycolysis.
Reasons for not completely oxidizing glucose and/or other nutrients (to CO2):
- lack of O2
- lack of genes for some enzymes of the cellular respiration process
Aerobic vs Anaerobic carbohydrate catabolism
Aerobic respiration -
O2 required (YES)
Phosphorylation (mostly oxidative phosphorylation)
Final e- Acceptor (O2)
ATP/Glucose (lots (30-32)
Fermentation -
O2 required (NO)
Phophorylation (substrate-level phosphorylation)
Final e- Acceptor (organic metabolite (pyruvate,..)
ATP/Glucose (Few (2))
What are the optimal conditions for microbial growth?
Chemical —> macro- and micronutrient, oxygen, water
*Nitrogen (N): Needed in higher proportion compared to humans due to the high nitrogen content in peptidoglycan (cell wall)
*Oxygen (O): Depends on species
Physical: temp., pH., osmolarity
*Growth rate highest at optimum pH of growth
*High Temperature
*Osmotic pressure pulls water out of cells
What are the phases of the microbial growth curve?
- Lag phase
- Log phase
- Stationary phase
- Death or decline phase
When is membrane filtration used?
Used when the cell count is low (a few cells per litre, ex: in drinking water, or lake or stream water)
T or F
Prokaryotic cells have one (haploid) chromosome, and eukaryotes have more than one (two—>diploid)
T
Where is the location of chromosomes in prokaryotes?
Eukaryotes?
Cytoplasm
In nucleus
What are plasmids?
- Small circular DNA molecules
- Replicate independently
- Do not contain essential genes for metabolism
- Some are called ‘factor’
= F factor = ‘fertility factor’
= ‘Virulence factor’; encodes for a capability of a strain or species to cause disease
= ‘Bacteriocin factor’; kill bacterial cells that are competitors
In the discussion of genetic recombination and transfer what is genetic recombination?
Exchange of segments, typically genes, between two DNA molecules
In the discussion of genetic recombination and transfer what is Recombinanats?
Cells with DNA molecules that contain one or more nucleotide sequence
In the discussion of genetic recombination and transfer what is vertical gene transfer?
An organism replicates its genome and provides copies to descendants, including permanent mutations; transfer from one generation to the next generation
In the discussion of genetic recombination and transfer what is horizontal gene transfer?
Donor cell contributes part of its genome to a recipient cell; transfer within generation —> important for genetic variability in species that have no sexual reproduction
What are the three horizontal gene transfer in prokaryote strange?
Transformation - > transduction -> conjugation
What are the three repetitions process steps of DNA amplification? (PCR gene technology)
Denaturing
Priming
Extension
Gene technology CRISPR stands for what? And is applied to what areas of research?
Clustered, regularly interspeced, short palindromic repeats
Medicine - biotechnology - agriculture - epidemiology
T or F
Reproduction in Eukaryotes is more complex and variable than in prokaryotes
T
What are the three types of asexual reproduction in eukaryotes through mitosis?
Binary fission
Budding
Schizogony
What is a schizont cell?
Cell filled with multiple nuclei
T or F
The terms schizont and merozoites are related to asexual reproduction and mitosis
T
Sexual reproduction requires what?
The formation of gametes through the process of meiosis:
Meiosis One diploid nucleus —-> four haploid nuclei
—> for genetic variability, during meiosis (the maternal and paternal chromosomes get randomly reasserted into new sets) (recombination of genes through ‘cross-over’ process)
What are the three forms of fungi growth?
Filamentous growth (hypha = fungal filament; plural is hyphae); many hyphae create a mycelium (typical for molds)
Yeast cells are single cells, which may from chains called ‘pseudo- hyphae’
Dimorphic species of fungo can grow as hyphae or yeast cells
T or F
Most fungi are anaerobic
F
Most are aerobic
T or F
All Fungi use asexual reproduction
T
Parasites are combinations of what two etiological agents of infectious disease?
Helminths
Protozoa
What are Protozoa?
Diverse group defines by three characteristics
- eukaryotic
-unicellular
-lack a cell wall
What are platyhelminths?
Flatworms
What are nematodes?
Roundworms
What are vectors in discussion of disease?
Are not causing the disease, but they are means by which infectious agents of disease are getting into a human host.
Which of the following describes a bacillus?
A. Sprial
B. Sphere
C. Rod
D. Curved rod
C
While __________ is/are only found in gram-positive cell walls, ___________ is found in gram-positive AND gram-negative cell walls.
A. Peptidoglycan; lipid A
B. Peptidoglycan; mycolic acid
C. Lipopolysaccharides; peptidoglycan
D. Teichoic acid; peptidoglycan
D
Which structures are not stainable, but are made visible through negative stains?
A. Capsules
B. Flagella
C. Mycolic acid
A
Which of the following groups of organisms do not perform fermentation?
A. Facultative anaerobes
B. Obligate aerobes
C. Aerotolerant microbes
D. Obligate anaerobes
B
Assign the following groups of etiologic agents of infectious disease to prokaryotes or eukaryotes:
Protozoa
Bacteria
Fungi
Viruses
Eukaryotes
Prokaryotes
Eukaryotes
Neither
Which of the following do NOT have cell walls?
A. Bacteria
B. Plants
C. Protozoa
D. Plants
C
The F factor is a _________
A. Gene
B. Pious
C. Plasmid
C
With PCR, one can
A. Recombine DNA
B. Multiply DNA
C. Delete genes
D. Edit genes
B
Which of the following are NOT etiologic agents of infectious diseases?
A. Ticks
B. Viruses
C. Prions
D. Parasites
A
The bacteria of medically relevant genera that are capable of producing endospores are ____________.
A. Gram-positive rods (bacilli)
B. Gram-positive spheres (cocci)
C. Gram-negative rods (bacilli)
D. Gram-negative spheres (cocci)
A
Match the bacterial species with the correct condition.
Clostridium Tetani
Clostridium Botulinum
Clostridium Perfingens
Bacillus Cereus
CT - Lockjaw
CB - Gastro-intestinal infection in infants
CP - Gas Gangrene
BC - Food poisoning
Which of the following is NOT a factor that exerbates the rapid transmission of infections?
A. Global travel
B. Urbanization
C. Global travel
D. Whether it is bacterial, viral or fungal
D
The sub groups of A-cellular parasites are?
A. Eukaryotes and prokaryotes
B. Viruses, Viroids, prions
C. Bacteria, fungi, bacteria
B
T or F
Eukaryotic cells are approximately 10 times larger than prokaryotic cells
T
The term “virion” refers to what?
An individual virus particle
T or F
All viruses contain DNA and RNA
F
All viruses contain DNA OR RNA
T or F
All Viruses have to have glycoproteins
T
These glycoproteins enable the virus to attach itself to host cells without attachment there is no infection
A capsid is:
A. Made of multi-subunit protiens (capsomer), surrounds nucleic acid, and varies in shape
B. Made of multi-subunit proteins, and has one set shape
C. Feeder protein for glycoproteins attachment
D. All of the above
A
FITB
Many animal/human viruses are surrounded by a lipid bilayer called __________.
Grouping of viruses into _____-_________ or naked and _________ __________.
Envelope
No enveloped or naked and enveloped virus
What is a bacteriophage? What does it do?
A bacteriophage is a type of virus that specifically infects and replicates within bacteria.
- infect bacteria, built to ‘inject’ DNA into host cells; involved in the process of transduction
Name the classifications and taxonomy of viruses.
What groups there classification?
- Type of nucleic acid (genomes size)
- DNA - RNA
- double stranded - single stranded
- 1 or multiple nucleic acid fragments
- Type of organism/tissue targeted
- Capside morphology (helical, plyhedral, complex)
- Enveloped - Non-enveloped (naked)
- For most viruses, family is the highest level of taxonomic order
Arboviruses are:
A. Type of organism/tissue targeted
B. Capside morphology
C. Viruses transferred by host to another host
D. Viruses that are transmitted by arthropod vectors
D
T or F
Viruses recruit the host cells metabolic pathways to increase their own numbers.
T
T or F
Viruses have and extracellular and intracellular state
T
T or F
Viruses can carry out any metabolic pathways
F
Cannot carry out any metabolic pathway
T or F
Viruses grow and respond to the environment
F
Neither grow nor respond to the environment
T or F
Viruses cannot reproduce independently
T
Name the 5 district stages of the ‘lytic cycle’
Bacteriophage = phage
- Attachment - the phage attaches to the surface of the host
- Penetration - the viral DNA enters the host cell *ENTRY
- Biosynthesis - Phage DNA replicates and phage protiens are made
- Maturation - New phage particles are assembled *ASSEMBLY
- Lysis - the cell lyses, releasing the newly made phages. *RELEASE
What is the name of the variation of the lytic cycle ? What is the difference between the two?
Lysogenic cycle
Attachment and entry are the same, but then the phage DNA does not take over command but inserts itself into the chromosome of the host cell.
What is the role of the immune systems response to viruses in animal hosts?
A. Synthesis the virus
B. Fight or flight internal response
C. Easily recognises extracellular virus, and can get alerted to a virus taking over a cell
D. Alert the lymphatic system to flush the virus
C
What are the five stages of viruses in animal hosts? Briefly describe them.
- Attachment - lectin binding sites
- Entry - three processes (depends on virus); naked (non-enveloped) viruses; enveloped viruses
- Synthesis - biosyntheses; depends on the type of genome (DNA or RNA, single strand or double) variation in:
- location in the host cell
PROCESS: Source of mRNA or protein synthesis, template for nucleic acid replication; For DNA viruses: use of mechanisms of host cells - Assembly
- Most DNA viruses assemble in the nucleus
- Most RNA viruses assemble in the cytoplasm
The number of new virions depends on: Type of infected cell; Type and size of virus; Health of infected cell - Release - Naked viruses released by exocytosis by or lysis of the host cell
Enveloped viruses:
- Gradual release over time
- Eventually the host cell will run out of resources and energy and lyse
T or F
With the latency of animal viruses are only possible for double stranded DNA viruses
T
T or F
Some latent viruses get incorporated into host DNA
T
T or F
Some latent viruses do not get incorporated into host chromosomes
T
T or F
Is is estimated that 20-25% of human cancers are caused by viruses
T
T or F
The incorporation of viral DNA into chromosomes causes mutations
T
Differentiate cellular prion protein and rogue prion protein.
Cellular prion protein: found in all mammals;
- Structure = all alpha-helices
*Harmless and does not cause disease itself
Rogue prion protein:
- Structure = Misfolded, containing some beta-sheet
*Infectious and induces normal protiens to adopt the misfolded structure, leading to a cascade of abnormal protiens accumulation.
Name some of the effects of Prion Protein Misfolding.
- The misfolded proteins from plaques
- Nervous tissue becomes sponge-life (brain cells die)
- The conditions are called ‘transmissible spongiform encephalopathies’ (TSE)
- Brain damage leads to loss of motor coordination and dementia
- Rapidly progressing
- No cure
T or F
There is possibility of transmission of animal prion disease only known for BSE (bovine spongiform encephalopathy, aka ‘mad cow disease.
T
The lytic cycle
- Attachment - Entry - Replication - Assembly - Release
This is the process in which a virus infects a host cell, takes over the cell’s machinery to make more viruses, and then causes the cell to burst open releasing new viruses to infect other cells.
Lytic cycle vs Lysogenic cycle
Lytic cycle virus actively replicates within the host cell, using the host’s machinery to produce new viruses particles
Lysogenic cycle integrates its genetic material into the host cell’s genome, where it can remain dormant for. Along time. The viral DNA cow called provirus, is copied along with the host’s DNA during cell division.
Naked (non-enveloped viruses) viruses vs enveloped viruses
Naked viruses - bind to a host cell surface and inject their DNA into the host cell’s genome in a manner similar to bacteriophages.
Enveloped viruses- bind to receptors on the host cell and the entire capsid enters the cell and opens releasing the viral genetic material into the cytoplasm of the cell
Compare and Contrast +RNA viruses and -RNA viruses
Translation (Biosynthesis)
+RNA viruses = the RNA can directly serve as mRNA for protein synthesis
-RNA = the RNA cannot be directly translated; it must first be converted to +RNA (mRNA)
Define Fomite
Inanimate objects that may harbor microbes and aid in their transmission
EX: doorknobs, phones, computer keyboards, towels, etc.
Define Disinfection
Removal of potential pathogens from fomites
Define antisepsis
Anti- = against or opposed to
-sepsis = decay or infection
Removal of potential pathogens from living tissue
Define sanitization
Removal of pathogens from objects to meet public health standards
Define pasteurization
Use of heat to destroy pathogens and reduce number of spoilage microorganisms in foods and beverages
Define sterilization
Destruction of all microorganisms and viruses in or on an object
Name the 5 physical methods of controlling virus spread
Temp., pH, osmolarity, radiation, filtration
What is autoclaving?
Moist heat under pressure
Antibacterial drugs, commonly called antibiotics
Antiviral drugs
Antifungal drugs
Antiprotozoan drugs
Antihelminthic drugs
Are all examples of what?
Most anti microbial drugs that are effective against only one type of microorganism.
What are semisynthetic ?
Semi- = half or partially
-synthetic = artificial or compose
Chemically modified natural antimicrobial
What antimicrobial drug is produced by an organism? From mold (natural)
Penicillium
How do antivirals work?
They target the ‘attachment’ step through competitive binding, most are very specific for one type of virus.
Name the 4 chemical methods of viral control.
Alcohol, halogens, phenols, surfactants
Name the three types of symbiotic relationships.
A. Bacteria, colon, commensalism
B. Parasitism, mutualism, colon
C. Mutualism, commensalism, parasitism
D. Benefits, symbiotic, mutualism
C
T or F
Mutualism benefits a human
T
T or F
Parasitism causes harm to a human
T
T or F
Commensalism neither benefits nor harms a human
T
What are microbiota?
Organisms that colonize the body’s surfaces without causing disease
- also called (normal flora, indigenous microbiota, microbiome)
Name the two types of microbiota.
Resident microbiota, transient microbiota
What are transient microbiota?
In or on the body for a short period of time.
May occur in other regions of the body as resident microbiota.
Disappear because of
- competition
- elimination
- chemical or physical changes
T or F
Normal microbiota becoming pathogens is called opportunistic pathogens
T
Cannot cause disease in healthy individuals, unless bacteria are introduced to an unusual site
T or F
Opportunistic pathogens can cause disease in (immune-) compromised individuals
T
What are disease reservoirs?
Reservoirs are ‘sites’ where pathogens can linger for a while and from where we can acquire them:
- animal reservoirs
- human carriers
- inanimate reservoirs
What is zoonoses (singular zoonosis)?
Infectious diseases that can be transmitted from an animal to a human host
What are the 4 pathways through which microbes enter the body?
- skin
- mucous membranes
- placenta: congenital infections
- parenteral route: broken skin or mucous membranes
Define pathogenicity
Ability of a microbe to cause disease
Define virulence
Degree of pathogenicity
(Pathogenicity = refers to the ability of a microorganism to cause disease in a host organism.)
Name the virulence factors of infectious agents.
Contribute to virulence:
-Adhesion factors
-Biofilms
-Extracellular enzymes (typically lysine extracellular structural biomolecules)
-Toxins
-Antiphagocytic factors
- intracellular state
Name the three modes of transmission.
A. Contact (direct, indirect, droplet); Vehicle (airborne, waterborne, food borne); Vector (biological, mechanical)
B. Portal, reservoir, contact
C. Vehicle, contact, host;s portal of entry
A
T or F
Many respiratory viruses can be spread before experiencing symptoms
T
Opportunistic pathogens
A. Cause disease in compromised individuals
B. Have well-developed virulence factors
C, are always pathogens
A
In which of the following types of symbiotic relationship does one organism benefit, while the other neither benefits nor is harmed?
A. Mutualism
B. None of these options are correct
C. Commensalism
D. Parasitism
C
Which of the following descriptions fits the term ‘prodromal’ stage of disease?
A. No sings or symptoms yet
B. Vague general symptoms
C. Declining signs and symptoms
D. Most severe signs and symptoms
B
Sterilizing under pressure with very hot steam is called?
A. Pasteurising
B. Autoclaving
C. Incinerating
D. Boiling
B
Which of the following are most likely to survive harsh antimicrobial methods?
A. Enveloped viruses
B. Gram-negative bacteria
C. Endospores
D. Protozoa cysts
C
Which of the following is NOT a target of any antibiotics?
A. Nucleic acid synthesis
B. Cell walll synthesis
C. Protein synthesis
D. Capsule synthesis
D
Which is the correct stage of viral replication?
A. Entry - attachment - synthesis - assembly - release
B. Attachment - entry - synthesis - assembly - release
C. Entry - synthesis - assembly - attachment - release
B
Which of the following nucleic acid - based groups of viruses can be latent and have the potential to cause cancer?
A. Single stranded DNA
B. Double stranded RNA
C. Double stranded DNA
C
Viral envelopes are ___________ structures
A. Predominantly protein
B. Membrane-like
C. Cell-wall-like
D. Polysaccharide
B
Prion diseases affect the
A. Respiratory tract
B. CNS
C. Circulatory system
D. Digestive tract
B
In the five stages of infectious disease the incubation period involves?
No signs or symptoms
In the five stages of infectious disease the illness involves
Most severe signs and symptoms
In the five stages of infectious disease the decline stage involves
Declining signs and symptoms
In the five stages of infectious disease the convalescence stage involves
No signs or symptoms
What is an example of an a-cellular etiologic agent of an infectious disease?
Viruses, Viroids, Prions
Which of the following is NOT found in all bacterial cells?
A. Cytoplasm
B. Cell wall
C. Capsule
D. You
C
T or F
Capsules can only be made visible with the negative stain
T
What do all pro- and eukaryotic cells have in common?
Cellular
Ribosomes
Microaerophiles are organisms that thrive in?
Low oxygen concentrations
T or F
Capsules are only found in some prokaryotes
F
Which form of radiation is recommended to keep surfaces sterile?
UV Radiation
What is the target of penicillin within the organism?
Cell wall
In this phase of growth a microbial population adapts to the growth conditions.
Lag phase
Most microorganisms that are human pathogens are?
Mesophiles
The best method for longterm preservation of microbial cultures is ________.
Lyophilization
Explain schozogony
This is a form of asexual reproduction in eukaryotes.
- Unique to some Protozoa
- Nucleus undergoes many mitosis
- Cytoplasm divides later (creating multiple cells with smaller cytoplasms)
What are the mechanisms in sexual reproduction that form genetic variability?
- random assortment: chromosomes are randomly organised and separated into daughter cells; metaphase I of meiosis; ensures each gamete has a random assortment of chromosomes —> genetic diversity!
- crossover: occurs in prophase I; homologous chromosomes exchange segments during meiosis; paired chromosomes align closely and exchange equivalent segments of genetic material
Define hyphae
Define mycelium
Individual branch-like filaments that make up the mycelium of a fungus
Interwoven network of hyphae
Define saprophytic
Sapro- = rotten or decaying
-phytic = plant or growth
Feeding, absorbing or growing upon decaying organic matter
Which type of asexual reproduction is typical in yeast cells?
Budding
Parasites derive from which eukaryote type?
- helminths
- Protozoa
T or F
Protozoa has a cell wall
F
T or F
Protozoa are multicellular organisms
F
Define pseudopodia
A cellular extension of amoeboid cells used in moving and feeding
Pseud - = meaning false or deceptive
-podia = meaning foot
= false feet
Define amoeboid
Amoeb - = change or alteration
-oid = resembling
Unicellular organism that can change shape by extending and retracting pseudopods
Which are the ways Protozoa move?
- cilia
- flagella
- pseudopodia
What are the stages of protozoa’s life cycle?
- tophozoite stage (active feeding stage)
- cyst stage (dormant)
T or F
While a Protozoa is in trophozoite stage, it can resist stomach acid
F
It must by in the cyst stage (dormant, inactive, resting stage) to be able to resist the stomach acid or any adverse conditions
T or F
While a Protozoa is in trophozoite stage, it can resist stomach acid
F
It must by in the cyst stage (dormant, inactive, resting stage) to be able to resist the stomach acid or any adverse conditions
Which components are found in all prokaryotic cells?
- plasma membrane
- cell wall
- cytoplasm
- ribosome
- nucleoid
Would be in bacteria
Typical size of a prokaryotic cell is?
0.1-5 mm
Typical size of a eukaryotic cell?
10-100 mm
Coccus shape
Round
Vibrio shape
Curved rod
Coccobacillus shape
Short rod
Spirillum shape
Spirochete shape
Spiral shape
Long, lose, helical spiral
Bacillus cellular arrangement
Single rod
Streptobacillus cellular arrangement
Chain of rods
Many antibiotics target which organelle in the prokaryotic cell?
The ribosomes
What is the major component in a prokaryote’s cell wall?
Peptidoglycan
What are the two structural types of prokaryotic cells?
Gram-positive and gram-negative
Which prokaryotic cell wall is more complicated?
Gram-positive or negative and why?
Gram- negative because is has an outer membrane
What role does lipid A play within a lipopolysaccharide?
Triggers the immune response
T or F
In all species of prokaryotes, you can find a capsule
F
Obligate aerobes require
O2 for cellular respiration
Faculative anaerobes require
Best with oxygen, but can grow in anaerobic conditions
Aerotolerant anaerobes require
Not much, they can grow with or without the presence of oxygen
What is the lag phase?
No increase in # of living bacterial cells
What is the log/exponential phase?
Rapid bacterial growth, like an exponential curve
What is the stationary phase?
A plateau in the microbial growth
of chromosomes: prokaryotes vs eukaryotes
- prokaryotes: 1
- eukaryotes: >1
Define F factor
A fertility factor in bacteria; a DNA segment that confers the ability to form pili for conjugation and associated functions required for the transfer of DNA from donor to recipient. It may exist as a plasmid or be integrated into the bacterial chromosome
