0.0(0)
Studied by 0 people
View linked note
Call Kai
Learn
Practice Test
Spaced Repetition
Match
Flashcards
Knowt PlayCard Sorting
1/86
There's no tags or description
Looks like no tags are added yet.
Last updated 12:35 AM on 10/23/24
Name | Mastery | Learn | Test | Matching | Spaced | Call with Kai |
|---|
No analytics yet
Send a link to your students to track their progress
87 Terms
1
New cards
What are macronutrients required by microbes?
C, H, N, O, P, S.
2
New cards
What distinguishes micronutrients from macronutrients?
Micronutrients regulate body functions and are needed in small quantities, while macronutrients are structural nutrients needed in abundance.
3
New cards
Define autotrophs.
Autotrophs get carbon from CO2, which is inorganic.
4
New cards
What is the maximum temperature effect on microbial growth?
Enzyme activity decreases, leading to denaturation and cell death.
5
New cards
What are B cells responsible for in the immune system?
B cells produce antibodies.
6
New cards
What is the difference between sterilization and disinfection?
Sterilization is the complete removal of viable microorganisms and endospores, while disinfection removes all biological entities except endospores.
7
New cards
Define passive immunization.
Immediate but temporary protection used in emergencies or when immediate immunity is needed.
8
New cards
What term is used for microbes that can survive in high salt conditions?
Halophiles.
9
New cards
What are extreme thermophiles?
Organisms that thrive at extremely high temperatures (65–121°C).
10
New cards
What does the term 'antibiotic' refer to?
A substance that kills or inhibits microbes.
11
New cards
What role does nitrogen play in microbial growth?
Nitrogen is essential for the synthesis of amino acids and nucleotides.
12
New cards
Define prototrophs.
Prototrophs are organisms that can synthesize all their amino acids and growth factors from basic nutrients.
13
New cards
What are the effects of pH on microbial growth?
Microbes have optimal pH ranges for growth; extreme deviations can inhibit enzyme activity and growth.
14
New cards
What is the main function of T cells in the immune system?
T cells are responsible for cell-mediated immunity and help in destroying infected or cancerous cells.
15
New cards
Describe the process of fermentation.
Fermentation is a metabolic process that converts sugars to acids, gases, or alcohol in the absence of oxygen.
16
New cards
What are biofilms?
Biofilms are communities of microorganisms that attach to surfaces and are encased in a protective extracellular matrix.
17
New cards
What is the significance of enzymes in microbial growth?
Enzymes catalyze biochemical reactions that are essential for microbial metabolism and energy production.
18
New cards
What are anaerobes?
Anaerobes are microorganisms that thrive in environments without oxygen.
19
New cards
What is the purpose of the Gram stain?
The Gram stain differentiates bacterial species into two major groups: Gram-positive and Gram-negative based on cell wall composition.
20
New cards
What do probiotics do?
Probiotics are live microorganisms that confer health benefits to the host, particularly improving gut health.
21
New cards
What is sterilization in microbial control?
Complete removal of viable microorganisms and endospores.
22
New cards
What is disinfection?
Removal of all biological entities except endospores; used on inanimate objects.
23
New cards
What does antisepsis entail?
Removal of vegetative pathogens; used on animate living things.
24
New cards
Which microbes are the most resistant and the least resistant to control methods?
Endospores are the most resistant, while enveloped viruses are the least resistant.
25
New cards
What does -cidal and -static mean in microbial control?
-Cidal refers to agents that kill microbes, while -static refers to those that inhibit growth.
26
New cards
How does temperature affect the effectiveness of chemical control methods?
Higher temperatures generally increase the effectiveness of chemical control agents.
27
New cards
What are critical instruments in terms of microbial control?
Instruments that come into direct contact with sterile body areas, requiring sterilization.
28
New cards
What factors influence the death rate of microorganisms under specific conditions?
The death rate is a constant percentage of microbes killed per time unit, impacting how quickly a population decreases.
29
New cards
What microbial targets are affected by control methods?
Cell membrane, proteins/enzymes, DNA/RNA, and cell wall.
30
New cards
Define 'antibiotic'.
A substance that kills or inhibits microbes.
31
New cards
What is selective toxicity in antimicrobial chemotherapy?
The ability of a drug to target microbes without harming the host.
32
New cards
Describe the spectrum of activity of an antimicrobial.
The range of pathogens that a drug affects, such as bacteria or fungi.
33
New cards
When would you use broad-spectrum vs narrow-spectrum antimicrobials?
Broad-spectrum is used when the pathogen is unknown; narrow-spectrum targets specific pathogens.
34
New cards
What are the three groups of resistant bacteria?
Inherently resistant, those that develop resistance through spontaneous mutations, and those that acquire resistance from other resistant microbes.
35
New cards
How do antibiotic-resistant microbes develop resistance?
By degrading antibiotics, modifying targets, or altering drug transport.
36
New cards
What are the major targets of antibiotics in bacteria?
Cell wall, protein synthesis, nucleic acids, metabolic pathways, and cell membrane.
37
New cards
How does antimicrobial resistance arise within a bacterial population?
Through overuse, misuse, and incomplete treatments.
38
New cards
What is the effect of broad-spectrum antibiotics on the human microbiome?
They disrupt the microbiome by killing beneficial microbes, increasing the chance for antibiotic resistance.
39
New cards
Why can using multiple antibiotics delay resistance?
It combines different mechanisms of action, reducing the likelihood of developing resistance.
40
New cards
What is the role of the immune system?
Protects against microbial pathogens by identifying and eliminating harmful invaders.
41
New cards
What are the three lines of defense in the immune system?
1. Physical barriers: Skin and mucous membranes. 2. Innate immunity: Fast and non-specific response with phagocytic cells. 3. Adaptive immunity: Slow and specific response involving B cells and T cells.
42
New cards
Why is skin a better barrier than mucous membranes?
Skin (epidermis) is a tougher barrier that prevents viral penetration due to its dead cell layer, while mucous membranes are more permeable.
43
New cards
What is microbial antagonism?
The competition of normal microbiota with harmful microbes, reducing pathogen colonization.
44
New cards
Why is distinguishing self from non-self important in the immune system?
To prevent the immune system from attacking the body's own cells while eliminating pathogens.
45
New cards
What is the primary goal of innate cellular immunity?
To provide a quick response to pathogens as the first line of defense.
46
New cards
List some characteristics of the innate immune system that are beneficial.
Available from birth, fast-acting, and offers resistance to a wide variety of microorganisms.
47
New cards
What are the major deficiencies of the innate immune system?
Lacks targeted responses, does not adapt, and can cause damage to the host.
48
New cards
Define 'antigen' in relation to the immune response.
Molecules that trigger an immune response.
49
New cards
What is the function of B cells in the immune system?
B cells produce antibodies to neutralize pathogens.
50
New cards
What does it mean for the adaptive immune response to have 'memory'?
It remembers previous encounters with pathogens for a faster and more effective response upon re-exposure.
51
New cards
What is passive immunization?
Immediate but temporary protection used in emergencies, such as after exposure to toxins or viruses.
52
New cards
How do whole agent vaccines differ from inactivated vaccines?
Whole agent attenuated vaccines contain live pathogens that are less virulent, while inactivated vaccines contain killed or inactivated pathogens.
53
New cards
What are the benefits and concerns regarding attenuated live vaccines?
Benefits: Activate T and B cells for long-lasting immunity. Concerns: Potential reversion to virulence, especially in immunocompromised individuals.
54
New cards
What are viral vector vaccines?
Vaccines that use a non-pathogenic virus to deliver pathogen antigens, combining features of both whole agent and subunit vaccines.
55
New cards
What are the potential side effects of vaccination in an outbred population?
Localized reactions, systemic reactions like fever, muscle aches, and rare allergic reactions.
56
New cards
Describe herd immunity.
Herd immunity occurs when a significant portion of a population is immune, reducing the spread of disease to those who cannot be vaccinated.
57
New cards
What are environmental conditions that affect microbial growth?
Temperature, pH, oxygen levels, hydrostatic pressure, osmotic pressure, and levels of radiation.
58
New cards
What effect does high temperature have on microbial enzymes?
Too high temperatures cause enzyme denaturation, leading to cell death.
59
New cards
What are obligate aerobes?
Microbes that require oxygen for survival.
60
New cards
What are obligate anaerobes?
Microbes that cannot survive in the presence of oxygen.
61
New cards
Define aerotolerant anaerobes.
Microbes that do not use oxygen but can tolerate its presence.
62
New cards
What are facultative anaerobes?
Microbes that can grow with or without oxygen, switching to anaerobic metabolism when oxygen is not available.
63
New cards
Define neutrophiles.
Microbes that thrive at neutral pH levels between 6-8.
64
New cards
What are acidophiles?
Microbes that prefer acidic pH levels, usually between 1-4.
65
New cards
What are alkaliphiles?
Microbes that thrive in alkaline environments, usually with a pH of 9 or greater.
66
New cards
What are barophiles?
Microbial organisms that can survive in high levels of pressure.
67
New cards
What are halophiles?
Microorganisms that prefer or can tolerate high levels of salt.
68
New cards
What are biofilms?
Multicellular communities of microorganisms covered by a protective exopolysaccharide layer.
69
New cards
What happens to enzyme activity at the minimum temperature?
Growth is slow, and enzyme activity is minimal.
70
New cards
What are extreme thermophiles?
Microbes that thrive at extremely high temperatures, typically between 65-121°C.
71
New cards
What is temperature's effect on microbial growth in the optimal range?
Microbial growth is fastest, and enzymes work at peak efficiency.
72
New cards
Define psychrophiles.
Microbes that prefer cold environments, usually below 15°C.
73
New cards
What is autoclaving?
A sterilization method using high pressure and steam at 121°C to kill all microbes and spores.
74
New cards
What is the purpose of pasteurization?
To reduce microbial load without sterilizing, effectively destroying pathogens.
75
New cards
How does boiling affect microbial life?
Boiling kills most pathogens but does not sterilize, as it does not kill endospores.
76
New cards
Why is oxygen important for microbes?
Oxygen is vital for energy generation but can produce damaging oxygen radicals.
77
New cards
What defines a capnophile?
Microbes that require high levels of carbon dioxide.
78
New cards
Where do obligate anaerobes grow in a thioglycolate broth?
At the bottom of the tube, where oxygen is absent.
79
New cards
Where do facultative anaerobes grow in a culture?
Throughout the medium but more concentrated at the top where oxygen is available.
80
New cards
What indicates whether an organism has detoxifying enzymes for oxygen?
Obligate aerobes and facultative anaerobes have all detoxifying enzymes; obligate anaerobes have none.
81
New cards
What is binary fission?
The process by which a single microbial cell divides into two identical daughter cells.
82
New cards
What occurs during the lag phase of bacterial growth?
Microbes acclimatize; nutrient uptake is happening but growth is minimal.
83
New cards
What characterizes the log phase?
Rapid microbial growth where the number of new cells exceeds dying cells.
84
New cards
Define generation time in microbial growth.
The time it takes for a microbial population to double in number.
85
New cards
How are total and viable cell counts different?
Total counts include both living and dead cells, while viable counts only reflect living cells.
86
New cards
What measurement unit is typically used for bacterial enumeration?
CFU/mL or cells/mL.
87
New cards
What effect does sampling have on growth curve analysis?
Sampling is necessary because counting all cells is impractical and allows for direct or indirect counting methods.
Flashcards (58)