I - Generalities Flashcards
(135 cards)
1
Q
Cells: DNA within a nuclear membrane
A
Eukaryotes
2
Q
Cells: Uses mitotic division
A
Eukaryotes
3
Q
Cells: DNA associated with histones
A
Eukaryotes
4
Q
Cells: Has more than one chromosome
A
Eukaryotes
5
Q
Cells: Has membrane-bound organelles
A
Eukaryotes
6
Q
Eukaryotes: Ribosomes
A
40s + 60s = 80s
7
Q
Cells: DNA within a nucleiod
A
Prokaryotes
8
Q
Cells: Uses binary fission
A
Prokaryotes
9
Q
Cells: Has only one chromosome
A
Prokaryotes
10
Q
Prokaryotes: Ribosomes
A
30s + 50s = 70s
11
Q
Cell Walls: Plants & Algae
A
cellulose
12
Q
Cell Walls: Fungi
A
chitin
13
Q
Cell Walls: Diatoms
A
silica
14
Q
Cell Walls: Prokaryotes
A
peptidoglycan
15
Q
Cell Walls: Archaea
A
pseudopeptidoglycan
16
Q
Cell Walls: Protozoa & Animals
A
none
17
Q
An ancestral eukaryotic cell is thought to have engulfed the bacterial ancestor of
A
mitochondria
18
Q
An early eukaryotic cell, already possessing mitochondria, engulfed a photosynthetic bacterium and retained it in symbiosis resulting in
A
chloroplasts
19
Q
Microorganisms: Has cells
A
bacteria, fungi, protozoa & helminths
20
Q
Microorganisms: 0.02-0.2 μm
A
viruses
21
Q
Microorganisms: 1-5 μm
A
bacteria
22
Q
Microorganisms: 3-10 μm
A
fungi (yeasts)
23
Q
Microorganisms: 15-25 μm
A
protozoa & helminths (trophozoites)
24
Q
Microorganisms: Has either DNA or RNA
A
viruses
25
Microorganisms: Has both DNA & RNA
bacteria, fungi, protozoa & helminths
26
Microorganisms: Has no nucleus
viruses
27
Microorganisms: Has prokaryotic nucleoid
bacteria
28
Microorganisms: Has eukaryotic nucleus
fungi, protozoa & helminths
29
Microorganisms: Has no ribosomes
viruses
30
Microorganisms: Has 70s ribosomes
bacteria
31
Microorganisms: Has 80s ribosomes
fungi, protozoa & helminths
32
Microorganisms: Doesn't have mitochondria
viruses, bacteria
33
Microorganisms: Has mitochondria
fungi, protozoa & helminths
34
Microorganisms: Has a protein capsid and lipoprotein envelope
viruses
35
Microorganisms: Has a rigid wall with peptidoglycans
bacteria
36
Microorganisms: Has a rigid wall with chitin
fungi
37
Microorganisms: Has a flexible membrane
protozoa & helminths
38
Microorganisms: Motile
some bacteria, most protozoa & helminths
39
Microorganisms: Replicates via Binary Fission
bacteria
40
Microorganisms: Replicates via Budding or Mitosis
fungi
41
Microorganisms: Replicates via Mitosis alone
protozoa & helminths
42
Obligate intracellular but acellular parasites of plants, naked RNA, no human diseases
viroids
43
Mobile genetic elements
Transposons
44
DNA pieces that move readily from one site to another either within or between the DNA of bacteria, plasmids and bacteriophages
"jumping genes" (transposons)
45
DNA replication followed by insertion of a new copy into another site
Replicative Transposition
46
DNA is excised from the site without replicating and then inserts into the new site
Direct Transposition
47
Prions: Normal form of protein encoded by the host's chromosomal DNA, suceptible to protease and soluble in detergent
PrPc
48
Prions: Abnormal isoform of PrPc which modifies folding of normal prion-like proteins found in the body and has a high beta-sheet content
PrPres / PrPsc
49
Appearance of vacuolated neurons with loss of function and lack of immune response or inflammation
Spongiform Encephalopathies
50
Human Prion Diseases
Creuzfeld-Jakob (CJD, cortical), Kuru ("k/guria" - to shake, cerebellar), Variant CJD (vCJD), Gerstmann-Straussler-Scheinker (GSS), Fatal Familial Insomnia (FFI), Sporadic Fatal Insomnia (SFI)
51
Animal Prion Diseases
Scrapie (sheep/goat), Transmissible Mink Encephalopathy, Bovine Spongiform Encephalopathy (Mad Cow), Chronic Wasting Disease (mule/deer/elk)
52
Prions are _____ to standard viral disinfection procedures and have very long incubation periods as long as ____.
impervious, 30 years
53
Prions: Transmission
infected tissue, cuts in skin, transplantation of contaminated tissue (cornea), contaminated medical devices (brain electrodes), ingestion of infected tissue (cannibalism), inherited
54
Prions: Susceptible Populations
women and children of the Fore tribe in New Guinea, neurosurgeons, neurosurgery patients, transplant surgeons, transplant patients
55
Prions: Spectrum of Disease
loss of muscle control → shivering → myoclonic jerks and tremors → loss of coordination → rapidly progressive dementia → death
56
Prions: Treatment
none
57
Prions: Prevention
cessation of ritual cannibalism, elimination of animal products from livestock feed, disinfection of neurosurgical tools (5% hypochlorite, Na hydroxide, autoclaved at 15psi for 1 hour)
58
Bacteria: Spheres
cocci
59
Bacteria: Rods
bacilli
60
Bacteria: Spirals
spirochetes
61
Cocci: Pairs
diplococci
62
Cocci: Chains
streptococci
63
Cocci: Clusters
staphylococci
64
Smallest Bacteria
Mycoplasma
65
Largest Bacteria
Thiomargarita namibiensis
66
Largest Medically Relevant Bacteria
Borrelia burgdorferi
67
All bacteria have a cell wall composed of peptidoglycan except
Mycoplasma
68
sugar + peptide side-chains crosslinked by transpeptidase
peptidoglycan
69
Kill bacteria by cleaving the glycan backbone (β 1→4 linkage between GlcNAc and MurNAc) of the peptidoglycan
lysozymes
70
Facilitate the passage of small, hydrophilic molecules into the cell
porin proteins
71
Have thicker and multilayered peptidoglycan and teichoic acid
Gram (+)
72
Have thinner and single-layered peptidoglycan, lipopolysaccaride and periplasmic space
Gram (-)
73
The outer membrane of gram (-) bacteria contains _____ which consists of _____ and _____.
endotoxin (lipopolysaccharide), lipid A, O antigen
74
Only gram (+) bacteria with endotoxin
Listeria monocytogenes
75
Steps in Gram Staining
primary stain (crystal Violet) → mordant (Iodine) → decolorizing agent (Acetone) → counterstain (Safranin)
76
Bacteria not seen in Gram Stain
Treponema, Rickettsia, Mycobacteria, Mycoplasma, Legionella, Chlamydia
77
Essential Components of Bacteria: Lipoprotein bilayer without sterols
cytoplasmic membrane
78
Essential Components of Bacteria: Site of oxidative and transport enzymes
cytoplasmic membrane
79
Essential Components of Bacteria: RNA and protein in 50s and 30s subunits
ribosomes
80
Essential Components of Bacteria: Protein synthesis
ribosomes
81
Essential Components of Bacteria: DNA, genetic material
nucleoid
82
Essential Components of Bacteria: Invagination of plasma membrane
mesosome
83
Essential Components of Bacteria: Participates in cell division and secretion
mesosome
84
Essential Components of Bacteria: Space between the plasma membrane and outer membrane
periplasm
85
Essential Components of Bacteria: Contains many hydrolytic enzymes including β-lactamases
periplasm
86
Non-Essential Components of Bacteria: Polysaccharide, protects against phagocytosis
capsule
87
Non-Essential Components of Bacteria: Glycoprotein, attachment, conjugation
pilus, fimbria
88
Non-Essential Components of Bacteria: Polysaccharide, mediates adherence to surfaces, biofilm
glycocalyx
89
Non-Essential Components of Bacteria: Protein, motility, H antigen (flagellin protein)
flagellum
90
1 Flagellum
Monotrichous
91
2 Flagella
Amphitrichous
92
Tuft of Flagella
Lophotrichous
93
Side Flagella
Peritrichous
94
Non-Essential Components of Bacteria: Keratin-like coat, dipicolinic acid, resistance to heat and chemicals
spore
95
Non-Essential Components of Bacteria: DNA, genes for antibiotic resistance and toxins
plasmid
96
Non-Essential Components of Bacteria: Glycogen, lipids, polyphosphates, site of nutrients in cytoplasm
granule
97
All bacterial capsules are composed of polysaccharide except
Bacillus anthracis (polypeptide of D-glutamate)
98
The capsule of Bacillus anthracis is composed of
polypeptide of D-glutamate
99
Formed by gram (+) rods especially Bacillus and Clostridium
spore
100
Extrachromosomal, double-stranded, circular DNA capable of replicating independently of the bacterial chromosome, can sometimes be integrated into the bacterial chromosome
plasmids
101
Plasmids: From cell to cell by conjugation, large, contain about a dozen genes for synthesis of the sex pilus and for the enzymes required for transfer
transmissible plasmids
102
Plasmids: Small, do not contain the transfer genes, frequently present in many (10-60) copies per cell
non-transmissible plasmids
103
Bacterial Growth Curve: Cells are depleted of metabolites as the result of unfavorable conditions, adaptation to new environment, nutrients are incorporated, vigorous metabolic activity but do not divide (zero growth rate)
Phase 1: Lag Phase
104
Bacterial Growth Curve: Rapid cell division occurs, β-lactam antibiotics act during this phase (constant growth rate), continues until either one or more nutrients in the medium become exhausted or toxic metabolites accumulate and inhibit growth
Phase 2: Log or Exponential Phase
105
Bacterial Growth Curve: Exhaustion of nutrients or the accumulation of toxic products cause growth to cease completely (zero growth rate), spores are formed
Phase 3: Maximum Stationary Phase
106
Bacterial Growth Curve: Most of the cells die because nutrients have been exhausted (negative growth rate)
Phase 4: Decline or Death Phase
107
Oxygen metabolism generates toxic products such as
superoxide, hydrogen peroxide
108
Enzymes needed to survive in aerobic environments
superoxide dismutase, peroxidase, catalase
109
Aerobic Bactera: Completely dependent on oxygen for ATP-generation
Obligate Aerobes
110
Aerobic Bactera: Uses fermentation but can tolerate low amounts of oxygen (< 0.2 atm) because they have SOD
Microaerophiles
111
Anaerobic Bactera: Utilize oxygen if it is present but can use fermentation in its absence
Facultative Anaerobes
112
Anaerobic Bactera: Exclusively anaerobic but insensitive to the presence of oxygen
Aerotolerant Anaerobes
113
Anaerobic Bactera: Cannot grow in the presence of oxygen because they lack 3 important enzymes
Obligate Anaerobes
114
Obligate Aerobes
Nocardia, Neisseria, Pseudomonas, Mycobacteria, Mycoplasma pneumoniae, Bordatella, Brucella, Bacillus cereus, Legionella, Leptospira
115
Obligate Anaerobes
Actinomyces, Bacteroides, Clostridium
116
Microaerophiles
Borrelia, Treponema, Campylobacter, Helicobacter, Streptococcus
117
Facultative Anaerobes
Bacillus anthracis, Escherichia coli, Listeria, Corynebacterium, Mycoplasma (non-pneumoniae), Staphylococcus
118
Aerotolerant Anaerobes
Propionibacterium, Lactobacillus vaginalis
119
Bacterial genetic material consists of _____ located in the _____.
single chromosome of circular DNA, nucleoid
120
Bacteria are _____ while eukaryotic cells are _____.
bacteria - haploid, eukaryotes - diploid
121
Bacterial DNA is _____ while human DNA is _____.
bacteria - circular, humans - linear
122
Extrachromosomal pieces of DNA encoding both exotoxins and enzymes
plasmids
123
DNA that moves readily from one site on the bacterial chromosome to another or from the bacterial chromosome to a plasmid
transposons
124
Movement of genes from inactive storage sites into active sites of transcription
Programmed Rearrangements
125
Prokaryote DNA transfer from one bacterium to another
Conjugation
126
Prokaryote DNA transfer by a virus from one cell to another
Transduction
127
Purified prokaryote/eukaryote DNA taken up by a cell
Transfromation
128
Cycles of Transduction
Lytic, Lysogenic
129
Occurs when normal flora occupy receptor sites preventing pathogens from binding
Colonization Resistance
130
Normal Flora: Skin
Staphylococcus epidermidis
131
Normal Flora: Nose
Staphylococcus aureus (anterior nares)
132
Normal Flora: Mouth
Viridans Streptococci
133
Normal Flora: Dental Plaque
Streptococcus mutans
134
Normal Flora: Colon
Bacteroides, Escherichia coli
135
Normal Flora: Vagina
Lactobacillus vaginalis (Döderlein), Escherichia coli, Streptococcus agalactiae
