MICROBIO Flashcards
(168 cards)
1
Q
What are microorganisms?
A
Life forms too small to be seen by the human eye
Microorganisms are diverse in form and function and inhabit all environments that support life.
2
Q
What is the cell structure of microorganisms?
A
Mostly single-celled; some form complex structures or are multicellular
Microbial communities often consist of microbes living together.
3
Q
What are the major roles of microorganisms in studying fundamental life processes?
A
- Molecular biology and biochemistry
- Genomics and molecular genetics
4
Q
What is the basic cell structure of a microbial cell?
A
- Cytoplasmic membrane
- Cytoplasm
- Ribosomes
- Cell wall (in some microbes)
5
Q
What are the key differences between prokaryotic and eukaryotic cells?
A
Prokaryotic: no organelles, no nucleus
Eukaryotic: contain organelles, DNA enclosed in nucleus
6
Q
What is the genetic material of eukaryotic cells?
A
Linear chromosomes within nucleus
Eukaryotic DNA is larger and more complex than prokaryotic DNA.
7
Q
What is the typical size range of prokaryotic cells?
A
0.2 µm to 600+ µm in diameter
Most prokaryotic cells range between 0.5–10 µm.
8
Q
Fill in the blank: The smallest microbe is _______.
A
Circovirus
9
Q
What are the three major domains of life?
A
- Bacteria
- Archaea
- Eukarya
10
Q
What is the significance of bacteriophages in microbiology?
A
They can target and kill antibiotic-resistant bacteria
Bacteriophages offer an alternative to traditional antibiotics.
11
Q
What is microbial ecology?
A
Interactions between microbes, animals, plants, and global ecosystems
12
Q
What role do nitrogen-fixing bacteria play in agriculture?
A
They are involved in nitrogen fixation in root nodules
Example: Rhizobium spp.
13
Q
How has the role of microorganisms in disease changed from 1900 to 2016?
A
1900: Infectious diseases were leading causes of death; 2016: Chronic diseases were leading causes.
14
Q
What are common shapes of microbial cells?
A
- Coccus (spherical)
- Bacillus (cylindrical)
- Spirillum (flexible spiral)
- Spirochete (rigid spiral)
15
Q
What is the typical pH of the stomach in the gastrointestinal tract?
A
pH ~2
16
Q
What are hyperthermophiles?
A
Microorganisms that thrive at temperatures up to 122°C
Example: Methanopyrus kandleri.
17
Q
What are the key products of fermentation pathways?
A
- Lactic acid (yogurt, cheese)
- Ethanol + CO₂ (wine, pickling)
18
Q
What is the primary function of ribosomes in microbial cells?
A
Protein-synthesising structures
19
Q
True or False: Most microbes are harmful to humans.
A
False
20
Q
What is fermentation?
A
Industrial production of chemicals, enzymes, pharmaceuticals
Fermentation is a metabolic process converting sugar to acids, gases, or alcohol using microorganisms.
21
Q
What are biofuels?
A
Conversion of biomass into ethanol, methane
Biofuels are renewable energy sources derived from organic materials.
22
Q
What are macronutrients?
A
Essential elements required in large amounts for cell growth
Macronutrients include carbon, nitrogen, and others critical for microbial growth.
23
Q
What are micronutrients?
A
Essential trace metals and growth factors required in minute amounts
Micronutrients support enzyme functions and cellular processes.
24
Q
What are the major elements that make up ~96% of dry weight in cells?
A
- C
- O
- N
- H
- P
- S
These elements are fundamental for all forms of life.
25
What is the role of nitrogen in microbial growth?
Found mainly in proteins, forms include NH₃, NO₃⁻, N₂
## Footnote
Nitrogen is essential for amino acid synthesis and other cellular functions.
26
Define defined media in microbial culture.
Media where the exact chemical composition is known
## Footnote
Defined media allow for precise control of nutrient availability.
27
What is a selective medium?
Medium that contains compounds inhibiting some microbes while allowing others to grow
## Footnote
Selective media are used to isolate specific types of organisms.
28
What is the purpose of the streak plate method?
Isolating pure cultures by minimizing contamination
## Footnote
This method involves spreading a sample over the surface of an agar plate.
29
What is the difference between total cell count and viable count?
Total cell count measures all cells, while viable count measures only living, reproducing cells
## Footnote
Viable counting methods include spread-plate and pour-plate techniques.
30
What is the Great Plate Count Anomaly?
Direct microscopic counts reveal more organisms than plate counts
## Footnote
Many microbes cannot grow under laboratory conditions, leading to underestimation in plate counts.
31
What is binary fission?
Cell division after the cell enlarges to twice its original size
## Footnote
Binary fission is the primary method of reproduction in prokaryotes.
32
What are the four phases of a typical microbial growth curve?
* Lag Phase
* Exponential Phase
* Stationary Phase
* Death Phase
## Footnote
These phases represent changes in population size over time.
33
What is generation time?
Time for cell number to double
## Footnote
Generation time varies among microbial species; for example, E. coli has a generation time of about 20 minutes.
34
What are biofilms?
Structured communities of microorganisms attached to surfaces
## Footnote
Biofilms can form on various surfaces, including medical devices and natural environments.
35
What are the cardinal temperatures for microorganisms?
Minimum, optimum, and maximum temperatures for growth
## Footnote
Each organism has specific cardinal temperatures that define its growth range.
36
Define acidophiles.
Microorganisms that grow best at pH < 5.5
## Footnote
Acidophiles thrive in acidic environments and have adaptations to maintain stability.
37
What is water activity (aw)?
Measure of the availability of water for microbial growth
## Footnote
Water activity affects microbial metabolism and growth rates.
38
What is the relationship between optical density and cell numbers?
Optical density is proportional to cell number within limits
## Footnote
A standard curve is required to relate optical density to actual cell counts.
39
What adaptations do psychrophiles have for cold environments?
* More α-helices than β-sheets
* More polar amino acids
* Fewer weak bonds
## Footnote
These adaptations help maintain protein function at low temperatures.
40
What is the significance of heat-stable enzymes?
Resist denaturation at high temperatures, allowing for industrial applications
## Footnote
Examples include Taq polymerase used in PCR.
41
What is the intracellular pH range for macromolecule stability?
pH 5–9
## Footnote
This range is critical for maintaining the stability of macromolecules within cells.
42
What is the function of buffers in microbial culture media?
To maintain constant pH
## Footnote
Buffers are essential for providing a stable environment for microbial growth.
43
Define water activity (aw).
Availability of water for microbial growth, ranging from 0 to 1
## Footnote
0 indicates no free water, while 1 indicates pure water.
44
What is osmosis?
Movement of water from high to low concentration
## Footnote
This process is crucial for maintaining cellular integrity and function.
45
What are halophiles?
Organisms that grow best at aw = 0.98 and have a NaCl requirement
## Footnote
They thrive in high salt concentrations, such as seawater.
46
What characterizes extreme halophiles?
Require 15-30% NaCl for growth, unable to grow at lower concentrations
## Footnote
These organisms are adapted to extremely saline environments.
47
What are compatible solutes?
Highly water-soluble molecules that help maintain positive water balance
## Footnote
Examples include sugars, alcohols, and glycine betaine.
48
What are the classes of microorganisms based on oxygen requirements?
Aerobes, Anaerobes
## Footnote
Aerobes require oxygen, while anaerobes do not.
49
What is the difference between obligate aerobes and facultative aerobes?
Obligate aerobes require O2; facultative aerobes can grow with or without O2
## Footnote
This distinction is important for understanding microbial growth conditions.
50
What is anoxic habitat?
Oxygen-free environments such as mud, bogs, marshes, and intestines
## Footnote
These habitats support anaerobic microorganisms.
51
What is the purpose of reducing agents in culture techniques?
To reduce O2 to water, creating an anaerobic environment
## Footnote
This is critical for the growth of anaerobic microorganisms.
52
What are toxic oxygen byproducts?
Reactive intermediates such as superoxide anion, hydrogen peroxide, hydroxyl radical
## Footnote
These byproducts can cause cellular damage in organisms exposed to oxygen.
53
What is the function of radical scavenging enzymes?
Break down toxic oxygen byproducts
## Footnote
Examples include catalase and superoxide dismutase.
54
Define decontamination.
Treatment to make an object safe to handle
## Footnote
This process is essential in microbiology to ensure safety.
55
What is the purpose of disinfection?
Targets pathogens, kills or severely inhibits growth
## Footnote
Disinfection does not necessarily eliminate all microorganisms.
56
What is heat sterilisation?
Most widely used sterilisation method
## Footnote
It effectively kills a wide range of microorganisms, including endospores.
57
What is the Decimal Reduction Time (D)?
Time required at a given temperature to reduce viability
## Footnote
This is a critical parameter in sterilisation processes.
58
What is an autoclave?
Sealed heating device using steam under pressure
## Footnote
It is effective for sterilising equipment and materials.
59
What does pasteurisation do?
Reduces microbial load in heat-sensitive liquids
## Footnote
It kills all known pathogenic bacteria but does not sterilise.
60
What is the wavelength range of ultraviolet (UV) radiation?
220–300 nm
## Footnote
This range is effective for damaging DNA and killing cells.
61
What is filter sterilisation used for?
Heat-sensitive liquids and gases
## Footnote
Filters allow passage of liquid/gas while trapping microorganisms.
62
What is the Minimum Inhibitory Concentration (MIC)?
Lowest agent concentration that inhibits growth
## Footnote
This is a key measurement in assessing antimicrobial efficacy.
63
What are bactericidal agents?
Kill microorganisms
## Footnote
Examples include bactericidal antibiotics.
64
What is the primary action of antibiotics?
Kill or inhibit bacterial growth
## Footnote
They target essential processes in bacteria.
65
What are the major targets of antibiotics?
* DNA replication
* RNA synthesis
* Protein synthesis
* Cell membrane and wall
## Footnote
These targets allow for selective toxicity against bacteria.
66
What is antibiotic resistance?
Acquired ability of microorganisms to resist chemotherapeutic agents
## Footnote
This resistance can arise through mutations or gene transfer.
67
What are the mechanisms of antibiotic resistance?
* Modification of drug targets
* Enzymatic inactivation
* Efflux pumps
* Metabolic bypass
## Footnote
These mechanisms allow bacteria to survive despite the presence of antibiotics.
68
What is the difference between antibiotic resistance and persistence?
* Resistance: Genetic mutations or gene transfer
* Persistence: Phenotypic (non-genetic) adaptation
## Footnote
Resistance leads to growth in the presence of antibiotics, while persistence allows survival without growth.
69
What are the classes of antibacterial drugs targeting cell wall synthesis?
* β-lactams (penicillin, cephalosporins)
* Vancomycin
* Bacitracin
## Footnote
These drugs inhibit peptidoglycan synthesis, critical for bacterial cell wall integrity.
70
What are antiviral drugs' main targets?
* Nucleoside reverse transcriptase inhibitors (NRTIs)
* Protease inhibitors
* Neuraminidase inhibitors
## Footnote
These drugs target specific viral processes to inhibit replication.
71
What are antifungal drugs targeting?
* Ergosterol synthesis
* Cell wall synthesis
* Unique fungal processes
## Footnote
These targets are critical for the survival of fungal pathogens.
72
What is the first antibiotic resistance observed in Neisseria gonorrhoeae?
Penicillin resistance developed in the 1980s
## Footnote
This marked the beginning of multidrug resistance in this bacterium.
73
Which antibiotic was recommended after ciprofloxacin resistance in Neisseria gonorrhoeae?
Ceftriaxone + azithromycin
## Footnote
This combination was suggested as a treatment strategy to combat resistant strains.
74
What is critical for long-term solutions in antimicrobial treatment?
Development of new antimicrobial compounds
## Footnote
This approach aims to combat emerging drug resistance.
75
What process is used to enhance drug discovery?
Combinatorial chemistry
## Footnote
It accelerates the identification of new drug candidates.
76
What modification to vancomycin was observed to restore its efficacy?
Changing carbonyl oxygen
## Footnote
This modification led to intermediate resistance being overcome.
77
What is the limit of resolution for a light microscope?
~0.2 μm
## Footnote
This means that objects closer than this distance cannot be distinguished as separate.
78
What type of microscopy uses visible light to illuminate specimens?
Light microscopy
## Footnote
It includes various types like bright-field and fluorescence microscopy.
79
What is the role of immersion oil in microscopy?
Improves resolution
## Footnote
It prevents light loss due to refraction when using high magnification.
80
What are the two types of lenses in a compound light microscope?
Objective lens and ocular lens
## Footnote
The objective lens magnifies the specimen, while the ocular lens magnifies the image further.
81
What is the purpose of staining in microscopy?
Increases contrast
## Footnote
Staining helps visualize specimens that are otherwise difficult to see.
82
What type of stain differentiates based on cell wall structure?
Gram stain
## Footnote
It distinguishes between Gram-positive and Gram-negative bacteria.
83
What does Koch’s postulates establish?
A definitive link between a microbe and a disease
## Footnote
These postulates are critical for proving the causative agents of infectious diseases.
84
What is the significance of Louis Pasteur's swan-necked flask experiment?
Disproved spontaneous generation
## Footnote
This experiment showed that life does not arise from nonliving matter.
85
Who proposed the concept of chemolithotrophy?
Sergei Winogradsky
## Footnote
He linked specific bacteria to biogeochemical transformations.
86
What is the primary method for studying microbial communities without culturing?
Metagenomics
## Footnote
This approach allows direct analysis from environmental samples.
87
What is the primary role of ribosomal RNA (rRNA) in evolutionary studies?
Provides molecular data for phylogenetic tree construction
## Footnote
Its universal presence and slow mutation rate make it ideal for such studies.
88
What does the term 'Gram-positive bacteria' refer to?
Bacteria with a thick peptidoglycan layer that retains crystal violet
## Footnote
These bacteria typically appear purple under a microscope.
89
Fill in the blank: The first to describe microbes was _______.
Robert Hooke
## Footnote
He published his observations in Micrographia in 1665.
90
True or False: Gram-negative bacteria appear purple after Gram staining.
False
## Footnote
Gram-negative bacteria appear pink due to their thin peptidoglycan layer.
91
What is the difference between basic dyes and acidic dyes?
Basic dyes are positively charged, while acidic dyes are negatively charged
## Footnote
Basic dyes bind to negatively charged cell components.
92
What was a key contribution of Robert Koch to microbiology?
Developed solid media for obtaining pure cultures
## Footnote
His work laid the foundation for microbiological techniques.
93
What is cirrhosis?
A liver disease characterized by scarring and impaired liver function
## Footnote
Cirrhosis can lead to liver cancer.
94
What viruses are associated with cold sores and genital herpes?
Herpes simplex virus (HSV-1, HSV-2)
## Footnote
HSV-1 typically causes cold sores, while HSV-2 is more often associated with genital herpes.
95
What disease is caused by Human papillomavirus (HPV)?
Cervical cancer and genital warts
## Footnote
HPV is a significant risk factor for cervical cancer.
96
What is norovirus known for?
Causing viral gastroenteritis
## Footnote
Norovirus is highly contagious and often spreads through contaminated food or water.
97
What severe illness is caused by the dengue virus?
Dengue fever
## Footnote
Dengue fever can lead to severe flu-like symptoms and complications.
98
What pathogen causes fatal encephalitis?
Rabies virus
## Footnote
Rabies is transmitted through bites from infected animals.
99
What is Candida albicans associated with?
Oral thrush, vaginal yeast infections, systemic candidiasis
## Footnote
Candida albicans is a common fungal pathogen.
100
What type of infection is caused by Aspergillus spp.?
Aspergillosis (lung infection)
## Footnote
Aspergillus spp. can cause serious respiratory issues, especially in immunocompromised individuals.
101
What is Cryptococcus neoformans known for?
Cryptococcal meningitis
## Footnote
This fungal infection is particularly common in immunocompromised patients.
102
What disease is associated with Histoplasma capsulatum?
Histoplasmosis (lung infection from bird/bat droppings)
## Footnote
Histoplasmosis can be severe in immunocompromised individuals.
103
What is Pneumocystis jirovecii associated with?
Pneumocystis pneumonia (PCP) in HIV/AIDS patients
## Footnote
PCP is a common opportunistic infection in individuals with weakened immune systems.
104
What pathogen causes malaria?
Plasmodium spp.
## Footnote
Malaria is transmitted through the bite of infected Anopheles mosquitoes.
105
What infection is caused by Giardia lamblia?
Giardiasis (intestinal infection)
## Footnote
Giardiasis is often associated with contaminated water.
106
What disease is caused by Entamoeba histolytica?
Amebiasis (dysentery)
## Footnote
Amebiasis can lead to severe intestinal issues.
107
What is Toxoplasma gondii known for?
Toxoplasmosis (can affect pregnant women and immunocompromised individuals)
## Footnote
Toxoplasmosis can cause serious complications during pregnancy.
108
What disease is caused by Trypanosoma brucei?
African sleeping sickness
## Footnote
This disease is transmitted by tsetse flies.
109
What infection is associated with Leishmania spp.?
Leishmaniasis
## Footnote
Leishmaniasis is transmitted by sandfly bites.
110
What parasitic infection is caused by Schistosoma spp.?
Schistosomiasis (parasitic worm infection)
## Footnote
Schistosomiasis can cause significant health issues, including organ damage.
111
What bacterium causes Lyme disease?
Borrelia burgdorferi
## Footnote
Lyme disease is transmitted by ticks.
112
What bacterium is responsible for the plague?
Yersinia pestis
## Footnote
The plague led to the Black Death pandemic in the 14th century.
113
What are the common foodborne pathogens?
* Staphylococcus aureus
* Clostridia (e.g., Clostridium perfringens)
* Salmonella spp.
* Escherichia coli (E. coli)
* Campylobacter spp.
* Listeria monocytogenes
* Yersinia enterocolitica
* Bacillus cereus
## Footnote
These pathogens are responsible for various foodborne illnesses.
114
What is the role of the human microbiome?
A functional collection of diverse microbes in a specific environment
## Footnote
The human microbiome plays a crucial role in health and disease.
115
What is the difference between microbiome and microbiota?
Microbiome refers to the functional collection of microbes; microbiota refers to all microbes in a microhabitat
## Footnote
Microbiota can refer to specific areas, like skin microbiota.
116
What is the approximate number of microbes in the human microbiome?
Approximately 10^13 microbes
## Footnote
These microbes form complex communities and play vital roles in human health.
117
What are the three major bacterial phyla in the gut microbiota?
* Firmicutes
* Bacteroidetes
* Proteobacteria
## Footnote
These phyla are predominant in the human gastrointestinal tract.
118
What are the three enterotypes based on microbial composition?
* Enriched in Bacteroides
* Enriched in Prevotella
* Enriched in Ruminococcus
## Footnote
Enterotypes affect health and responses to diet and therapies.
119
What is the significance of intestinal microbial products?
* Vitamin synthesis
* Amino acid synthesis
* Gas and odor production
* Organic acid production
* Steroid metabolism
## Footnote
These products significantly influence host physiology.
120
What is the role of Lactobacillus acidophilus in the vagina?
Ferments glycogen to produce lactic acid, maintaining an acidic environment
## Footnote
This helps prevent infections.
121
What are the predominant organisms on sebaceous skin?
* Propionibacteria (45%)
* Staphylococci (15%)
* Corynebacteria (12%)
## Footnote
These bacteria are crucial for skin health.
122
What is the primary function of bile acids?
Facilitate lipid absorption, including fat-soluble vitamins
## Footnote
Bile acids are produced by the liver and stored in the gallbladder.
123
What is the primary characteristic of the human virome?
Most viruses in the human body are bacteriophages, not animal viruses
## Footnote
Bacteriophages play a protective role against pathogens.
124
What is the Human Microbiome Project (HMP)?
Mapped microbiomes to establish baselines for healthy humans
## Footnote
This project revealed greater diversity in non-U.S.-born subjects.
125
What factors influence the gut microbiome?
* Vaginal vs. cesarean birth
* Diet
* Environment
* Lifestyle
## Footnote
These factors can shape the composition of gut microbiota.
126
What is the role of mouse models in microbiome research?
Mice have a short life cycle, are genetically defined, and can be raised in germ-free environments.
## Footnote
Mouse models allow for the study of fecal transplants, strict diets, and antibiotic therapy.
127
When does colonization of the gut microbiota begin?
At birth with transfer from mother to infant.
## Footnote
Early microbes are facultative anaerobes and provide vitamins.
128
How does birth mode affect the gut microbiome of infants?
Vaginally born infants have a microbiome similar to their mother's, while Cesarean-born infants show delayed Bacteroides colonization.
129
What is the impact of breastfeeding on the gut microbiome?
Breastfed infants have a greater number of commensal bacteria due to oligosaccharides in breast milk.
130
What dominates the gut microbiome of breastfed infants early on?
Bifidobacterium and Bacteroides.
## Footnote
As solid foods are introduced, Firmicutes and other species become more abundant.
131
What are the effects of aging on the gut microbiome?
Microbiome stability decreases with age, particularly in the elderly, leading to a higher Bacteroides/Firmicutes ratio.
132
What characterizes Inflammatory Bowel Disease (IBD)?
Chronic gut inflammation and disruption of microbiome homeostasis with lower gut microbiome diversity.
133
How does obesity affect gut microbiota in mice?
Obese mice have different microbiota, specifically more Firmicutes and methanogenic Archaea.
134
What is the result of fecal transplant from obese individuals to mice?
It can cause obesity in mice.
## Footnote
Studies show microbiota transfer from obese individuals can lead to weight gain.
135
What types of bacteria are typically found in obese individuals?
Prevotella and methanogenic Archaea species.
136
What are the causes of dental caries and periodontitis?
Dental plaque (biofilm) with Streptococcus and fermenting bacteria causes tooth enamel erosion.
137
What is the systemic link associated with periodontal disease?
It is linked to systemic conditions like cardiovascular disease and arthritis.
138
What is the impact of antibiotics on the human microbiome?
Antibiotics decrease all microbes in the human gut, increasing the risk of IBD and promoting Clostridium difficile infections.
139
What happens to microbiome diversity after antibiotic therapy?
There is a loss of microbiome diversity, allowing C. difficile to flourish.
140
Fill in the blank: Vaginal delivery leads to early colonization of _______.
Bacteroides
141
True or False: Antibiotics in early life have no impact on the risk of dysbiosis-related disorders.
False
142
E: Aseptic technique refers to
a series of practices to avoid contamination
143
E: When a solution composed of bacteria and infectious v are mixed and spread on an agar plate. ______forms where viruses lyse the host cells
Plaques
144
E: Chemotrophy involves _____
acidation of inorganic compounds
145
E: During electron transport reaction
OH- accumulates on the inside of the membrane while H+ accumulates on the outside
146
E: A bacterium possessing ____will produce O2 bubbles when places in the presence of hydrogen peroxide
catalase
147
E: A surprising finding of environmental metagenomic studies is that a majority of genes in the environment are ____
viral in origin
148
E: For clinical medicine, a major consequence of phenotypic heterogeneity within populations of pathogens is the existence of ___
dormant cells that can cause reinfection after the pathogen was thought eradicated
149
E: Consider the following experiment. First, large populations of mutant strains of Ecoli are mixed, each requiring a different, single aa. After plating them onto a minimal medium, 45 collonies grew. Which of the following may explain this result
Either back mutation (reversion) or recombination is possible
150
E: A microbe growing in a refrigerator is likely
psychrotolerant or psychrophilic
151
E: Gene function is annotated based on homology between the ORFs of a genome and proteins whose has been proven experimentally. What "-omic" approach could help us determine the function as well as structure of proteins encoded by uncharacterized ORFs?
Proteomics
152
E: For a virus to cause a latent infection, it must possess___
dsDNA
153
E: What happens to the mutation rate when antibiotics are added to a bacterial culture
It doesn t change
154
E: The peptide interbridge crosslinking between peptidoglycan layers is found ONLY in the cell walls of ___
gram-positive Bacteria
155
E: A mutant that has a nutritional requirement for growth is an example of a(n)
auxotroph
156
E: When does endospore formation commence
when bacterial growth ceases due to limitation of an essential nutrient
157
E: A rumen is the location where active microbial populations ___ ___ the main component of plant cell walls, into usable nutrient sources for the animal .
ferment cellulose
158
E: A chemoorganotroph and a photoautotroph in the same environment would NOT compete for
carbon and oxygen
159
E: The majority of phyla from the domain Bacteria were discovered by
sequencing DNA extracted directly from environmental samples
160
E: Which bacterium is expected to be least susceptible to penicillin: Gram + , Gram -, Gram - bact which produces penicillinase (a type of beta lactamase)
Gram - bact which produces penicillinase (a type of beta lactamase)
161
E: Which of the following are NOT found in the gastrointestinal tract of healthy humans
Protists
162
E: A pure culture
is a population of identical cells
163
E: Based upon microbiome projects, the most dominant microbial species in sebaceous gland system is
Propionibacterium species
164
E: For bacteriophages and animal viruses ___ is the step in the viral life cycle that determines host cell specificity
attachment
165
E: If delta G0' is negative, the reaction is
exergonic and energy will be released
166
E: Enveloped viral membranes are generally___ with associated virus-specific___
lipid bilayers/proteins
167
E: Turbidity measurements are commonly utilized for monitoring
planktonic cultures
168
E: Which of the following statement is FALSE
Microbial cells include both bacteria and viruses
