Chapter 2 Flashcards
(138 cards)
1
Q
Human infectious diseases belong to five major groups of organisms which are:
A
Bacteria
Fungi
Protozoa
Helminths
Viruses
2
Q
Which pathogen is noncellular
A
Viruses
3
Q
Name the kingdoms of pathogens
A
Animals
Protists
Fungi
Prokaryotes
4
Q
Rank organisms from largest diameter to smallest
A
V<B<F<protozoa and helminths
5
Q
Which pathogen doesn’t have both nucliec acid
A
Viruses
6
Q
Diffrentiate between pathogens ribosomes
A
B: 70s from two subunits which are 50s and 30s
Eukaryotes: 80s from two subunits which are 60s and 40s
V: have none
7
Q
In which pathogens mitochondria are absent
A
V and B
8
Q
The outer surface of viruses nature
A
Protien capsid and lipoprotien envelope
9
Q
Are viruses molitile?
A
No
10
Q
Are all B molitile?
A
No, some of them
11
Q
How B replicates?
A
Binary fission
12
Q
How fungi repliates
A
Budding or mitosis
13
Q
How protozoa and helminths replicate?
A
Mitosis
14
Q
What are trophozoites?
A
the activated, feeding stage in the life cycle of certain protozoa such as malaria-causing Plasmodium falciparum
15
Q
How viruses replicate?
A
Viruses disassemble, produce many copies of their nucliec acids and proteins, then reassemble into multiple progeny viruses
-can’t replicate without a host cells
16
Q
Is there any histones in B
A
No
17
Q
What is the main component of B cell wall
A
Peptidoglycan
18
Q
In which pathogen’s wall chittin exists
A
Fungi
19
Q
Which is the only prokarote that has sterols in its cell membrane
A
Wall-less Mycoplasma
20
Q
Which pathogens are named according to binomial linnean
A
B, fungi, protozoa and helminths
21
Q
How is B named
A
First name: the genus
Second name: the species
22
Q
Bacterias shapes
A
Cocci: round
Bacilli: rod like
Spirochetes: spiral shaped
Vriable in shapes: pleomorphic
23
Q
What are the arrangements of the bacteria
A
Diplo: in pair
Staphylo: grapelike clusters
Strepto: in chains
24
Q
B size range
A
0.2 to 5 micrometer
25
The smallest bacteria and the smallest organism that capable of existing outside a host
Mycoplsma
26
The largest viruses
Poxviruses
27
Which B species don’t have cell wall
Mycoplasma
28
Surface features external to the cell wall
Capsule
Flagella
Pili
29
Which type of B has an outer layer and what its components are
Gram negative
-LPS
-Lipoprotein
-Phospholipid
30
What it the name of the space between the outer layer and cytoplasmic mem in gram -ve and what it contains
Periplasmic space and it has enzymes called B-lactamases that degrade penicillins and B-lactam drugs
31
What is the LPS that gram -ve has
Endotoxin
32
Why mycobacteria can’t be stained with gram stain
Mycobacteria, because it’s acid-fast so it resists decolorization with acid-alchohol after being stained with carbolfuchsin
33
The acid-fast property is related to
Mycolic acids in the cell wall of mycobacteria
34
Which structure allows the cell to withstand low osmotic pressure
Peptidoglycan
35
Synonyms for peptidoglycan
Murein
Mucopeptide
36
What is the structure of peptidoglycan
- carbohydrate backbone
- tetrapeptide
- peptide cross-links between two tetrapeptides
37
What is carbohydrate backbone composed of
NAM N-acetylmuramic
NAG N-acetylglucoamine
38
The most important staining procedure in microbiology
Gram stain
39
What are the stains of gram
+ve: purple
-ve: red
40
What are the steps of gram stain
1) crystal violet stains all cells purple
2) the iodine sol. is added to form crystal violet-iodine complex
3) the organic solvent
4) the red dye safranin
41
How we stain the cells purple
With crystal violet dye
42
Organic solvent that can be used in gram staining
Acetone or ethanol
43
How the organic solvent works on the cell
Extracts the purple dye from the lipid-rich, thin-walled, gram -ve cells
44
How the -ve cells appears after the organic solvent step
Colorless
45
Which cells are more susceptible to penicillin
Gram +ve
46
What drugs target the peptidoglycan
PCV:
Penicillins
Cephalosporins
Vancomycin
47
Which enzyme synthesis peptidoglycan and how
Transpeptidas: makes the cross-links between tetrapeptides
Inhibited by PCV
48
Where lysozyme presents
Mucus
Tears
Saliva
49
What lysozyme does
Breaks the glycosyl bonds in the carbohydrate backbone
50
Spherical forms of bacteria that survived lysozyme are called
Protoplasts
51
Bacteria that only surrounded by cytoplasmic mem.
Protoplats
52
Responsible for many features of disease in -ve
Endotoxin
53
Features of disease that are caussed by endotoxin
Fever
Shock
Hypertension
54
Why it’s called endotoxin
Because it is an integral part of cell wall that is in contrast to exotoxin
55
The constellation of symptoms caused by endotoxins
Similar but the severity of the symptoms can differ greatly
56
Bacteria that can’t be seen with gram stain
MTMLCR
Mycobacteria
Trepponema pallidum
Mycoplasma pneumoniae
Legionella pneumophila
Chlamydiae
Rickettsiae
57
Which B cant be gram stained because its small size
Chlamydiae
Rickettsiae
58
Which B cant be gram stained because it has too much lipid in cell wall
Mycobacteria
59
Which B cant be grm stained because it is too thin to be seen
Treponema pallidum
TT
60
Which B cant be gram stained because it has no cell wall
Mycoplasma pneumoniae
61
Which B cant be gram stained because it has poor uptake of red counterstain
Legionella pneumophila
62
Cell mem. Functions
Active transport
Energy generation - oxidative phospholyration
Synthesis of precursors of the cell wall
Secretion of enzymes and toxins
63
The distinct areas of cytoplasm
Amorphous matrix
Nucleoid
64
Targets for antibacterial drugs
Peptidoglycans
Ribosomes
65
Storage areas in the cytoplasm
Granules
66
Bacterias genome that has two chromosomes
Vibrio cholerae
67
The B that has a linear chromosome
Borrelia burgdorferi
68
The major difference between the human DNA and the B DNA is
B DNA has no intrions
69
Extrachromosomal, double stranded, circular DNA
Plasmids
70
Toxic component of endotoxin
Lipid A
71
Polymers of teichoic acid
Glycerol phosphate or ribitol phosphate
72
How teichoic acid links to the cell
- pentrate the PG layer and links to the cytoplasmic mem (lipoteichoic acid)
- anchor to muramic acid of PG
73
What causes inflammation and septic shock in gram +ve
Teichoic acid
74
Types of plasmids
Transmissible
Nontansmissible
75
The plasmid type that can transffer by conjunction
Transmissible
76
Transmissible olasids are
Large
77
How many copies the B have of each plasmid type
T: 1 to 3 copies
N: 10 to 60 copies
78
The plasmids that are responsible for sex pilus synthesis
Transmissible
79
Plasmids genes functions
Antibiotic resistance
Exotoxins
Pili
Resistance to heavy metals
Resistanve to ultraviolet light
Bacteeriocins
80
Bacteriocins
Toxic proteins produced by certain bacteria that are lethal for other bacteria
81
How do bacteriocins work
1- degradation of bacterial cell membrane by producin pores in the mem.
2- degradation of bacterial DNA with DNAse
82
Bacterocins made by E.coil
Colicins
83
Bacteriocins that are made by psedomonas aeruginosa
Pyocins
84
Treating antibiotic-resistant bacteria by
Bacteriocins
85
Jumping genes are
Transposons
86
Transposons are between
DNAs of bacteria
Plasmids
Bacteriophages
87
Types of trasposons
Replicative transposons
Direct transposons
88
how are you?
dying :)
89
how many domains do transposons have
4
90
how many inverted repeats are on the transposon
one on each side
91
what is the funtion of IR
integration of the transposon into the recipient DNA
92
what is the funtion of IR
integration of the transposon into the recipient DNA
93
what are the 4 domains of transposon
1) inverted repeats
2) the gene for teansposase
3) the repressor
4) enzyme mediating antibiotic resistance
94
what it is the gene for transposase function
an enzyme that mediates the excicion and integration process
95
what is the repressor function
regulates the synthesis of transposase and the enzyme that mediates antibiotic resistance
96
can transposons replicate by itself
no, unlike plasmids
97
can transposons move from bacterium to another
yes, conjugative transposons
98
what is the capsule and what is composed of
a gelatinous layer covers the whole B
- polysaccharides
99
which B its capsule isnt composed of PS and what is the alternative
- anthrax bacillus
composed of d-glutamic acid
100
what we call the difference in the sugar components of PS between bacteria
serologic type - serotype
101
importance of the capsule
1) determinant of virulence of many B
2) specific identification
3) antigens in certain vaccines
4) play a role in adherence
102
how does capsule has a role in determinant of virulance
- limits the ability of phagocytes to engulf B
- negative charge on PS repel the -ve charged cell mem. of neutrophil so it prevent the ingestion of the B
103
how does capsule has a role in determinant of virulance
- limits the ability of phagocytes to engulf B
- negative charge on PS repel the -ve charged cell mem. of neutrophil so it prevent the ingestion of the B
104
how does capsule play a role in identification
by using antiserum against the capsular PS
105
what is quellung rxn
when we use an antiserum in the presence of homologous antibody, the capsule will swell greatly. the swelling is used to identify certain organisms
106
why are capsules PS used in certain vaccines
because they are capable of eliciting protective bodies
107
how the B would be able to engulf the capsule
antibodies against the capsule neutrilize the antiphagocytic effect and allow the process
108
what is opsonization
an immune process which uses opsonins to tag foreign pathogens for elimination by phagocytes
109
flagella shape
long
whiplike
110
what is the process of flagella that moves the B toward nutrients and other attractants called
chemotaxis
111
flagella is composed of
many subunits of flagellin (single protein)
112
the energy to move flagella is provided by
proton motive force by ATP
113
which B dont have flagella
nonmolitile cocci
114
what is the importance of flagella
1) identification by some specific antibodies against flagellar proteins
2) a role in pathogensis by propelling the B up the urinary tract to the bladder
3) common cause of urinary tract inf. e.g. E. coli and proteus species
115
syn. for pili
fimbriae
116
spirichetes flagellum-like structue
axial filament
117
pili shape
hairlike filaments
shorter and staighter than flagella
118
pili are composed of
helical strands of pilin protein
119
in which gram cells pili are mainly found
-ve
120
a structure that mediate the attachment of B to human cells receptors
pili
121
mutants of which B do not form pili and are nonpathogen
neisseria gonorrhoeae
122
used in conjugation
sex pilus
123
what is glycocalyx
PS coating secreted by many B
124
how does glycocalyx work
it covers surfaces like a film and allows the B ro adhere firmly to various structures
125
examples of structures that glycocalyx adhere to it
skin
heart valves
prosthetic joints
catheters قسطرة
126
glycocalyx is an important component of
biofilms
127
medical importance of glycocalyx
it is the glycocalyx producing strains in P.aeriginosa and staphylococcus epidermidis and viridans streptococci
128
causes respiratory tract infictions in cytic fibrosis patients
P. aeruginosa
129
causes endocarditis
staphylococcus epidermidis and viridans streptococci
130
B adheres to the teeth by glycocalys and forms plaque
streptococcus mutant
131
plaque are
precursor of dental caries
132
Highly resistance structures are formed in response to adverse conditions
Bacterial spores
133
How many genra causes bacterial spores and what are they
Two
-bacillus
-clostridium
134
Which agent bacillus includes
Anthrax
135
Which agents clostridium includs
Tetanus
Botulism
136
When sporulation occus
When nutrients are depleted
137
Where the spores form
Inside the cell
138
How the spores form within the cell
With a thick, keratin like coat that giver resistance of the spores to heat, dehydration, radiation and chemicals
