Microbiology Flashcards
(95 cards)
1
Q
bacteria
A
single celled members of Eubacteria and Archaea prokaryotes most are decomposers some live naturally in the human body a few cause diseases some can live without oxygen some are photosynthetic and produce oxygen
2
Q
prokaryotes
A
no nucleus or membrane bound organelles
have smaller ribosomes than eukaryotes
have a cell wall
bacteria are prokaryotes
3
Q
eukaryotes
A
have a nucleus and membrane bound organelles, ribosomes, and some have a cell wall (plants and fungi)
protozoans, fungi, plants, and animals
4
Q
bacterial cell wall
A
made up of peptidoglycan (gram + or gram -)
may have flagella, fimbrae, pilli, glycocalyx
internally-single chromosome (circular, free floating), ribosomes, some may have plasmids or endospores
5
Q
gram +
A
thick layer of PG
6
Q
gram -
A
thin layer of PG with an outer membrane of lipopolysaccharides
7
Q
flagella
A
for movement
8
Q
fimbrae
A
hairlike structures for attachment to surfaces
9
Q
pilli
A
exchange ofDNA
10
Q
glycocalyx
A
sugar containing layer
can protect the bacteria or attach it to surfaces
11
Q
plasmids
A
small circular piece of DNA that replicates independently of the chromosome
12
Q
endospore
A
tough survival structure
found in Bacillus and Clostridium
13
Q
ribosome
A
slightly smaller than those of eukaryotes function different from ribosomes in eukaryotes
14
Q
cocci
A
round
15
Q
bacilli
A
rod-shaped
16
Q
spirals
A
loose or tight spirals
17
Q
Gram stain
A
positively charged stain
decolorizing with alcohol to remove stain from cells with thinner gram - walls
gram + =purple
gram - =safranin
18
Q
eneric/coliform bacteria
A
E. coli, Salmonella, and Shigella
cause infections of GI tract and serve as indicators of pollution
only found in the gut or in feces
19
Q
Mycobacterium
A
has outer layer of waxy lipid
causes TB and leprosy
20
Q
Clostridium
A
gram + rod
causes tetanus, botulism, and gas gangrene
21
Q
Borrelia
A
spirochete
causes Lyme disease transmitted by a tic
22
Q
Treponema
A
spirochete
causes syphillis
23
Q
protozoans
A
eukaryotic
single-celled
move using flagella, cilia, or amoeboid motion
24
Q
cyst
A
tough survival stage in protozoans
stages that transmits disease
25
trophozoite
stage in protozoans
| in this stage when not in cyst stage
26
malaria
caused by protozoans
| complex life cycle and mainly affects RBCs in humans and digestive tract in mosquitos
27
amebiasis
protozoan disease of the intestine
| caused by Giardia and Cryptosporidium
28
sleeping sickness
protozoan disease
goes from blood to brain
transmitted by the Tse Tse fly
29
toxoplasma
complex life cycle involving cats
| fetus can be infected if a woman gets this disease during pregnancy
30
fungi
single and multi cellular
decomposers-absorb nutrients from dead material
reproduce by sexual or asexual spores
spores can be involved in the transmission of fungal diseases and are most common causes of respiratory allergies
31
molds
multicellular fungi
composed of strands of cells all joined into one
some have chitin in their cell wall
Penicillium and mushrooms
32
yeasts
single-celled fungus
can carry out fermentation
important for production of bread, wine, and beer
33
lichens
symbiotic relationship between a fungus and algae
| algae provides food through photosynthesis, mold attaches to surface and absorbs nutrients
34
dermatophytes
fungi that cause diseases in the skin
break down keratin
ringworm-Epidermophyton and trichophyton
35
Candida
yeast
infects mouth, intestines, or vagina
often seen in immunosuppresed patients (HIV or chemo patients)
36
parasitic worms (helminths)
primitive flatworms and roundworms
lay large numbers of eggs
some form cysts inside of the tissues of their hosts which can then be involved in disease transmission
37
intestinal parasitic diseases
most common site for worms
| Ascaris, hookworms, pinworms, and tapeworm
38
Trichinella
worm
acquired from eating under cooked or uncooked pork
leaves intestines and forms cysts in muscles
39
Schistosoma
roundworm hookworm
| enter the body by drilling through skin
40
tapeworms
acquired by eating under cooked or uncooked beef, pork, or fish
41
viruses
smaller than all other organisms
simple structure- protein coat (capsid), nucleic acid/genome (DNA or RNA), some have an outer membrane (envelope)
not cells-no cell wall, cell membrane, nucleus, or organelles
not prokaryotes or eukaryotes
42
obligate intracellular paracites
must live inside of a host cell to help carry out normal cellular functions such as replication
43
replication of viruses
synthesis and assembly of subunits- many copies of the parts of the virus are made inside the host cell and then put together to make many viruses
44
stages of viral replication
attachment- host and tissue specific
penetration- virus enters host cell by endocytosis or fusion of the envelope
uncoating- genome released from inside the capsid
synthesis- host cell makes viral proteins and nucleic acid
maturation/assembly- viral subunits put together
release- virus exits host cell
45
latency
some viruses don't complete replication but exist as DNA inserted into the host's DNA
virus may reactivate and replicate at a later time
e.g. herpes, HIV, and chicken pox/shingles
46
viroids
atypical virus
| made up only of small pieces of RNA with NO PROTEIN
47
prions
atypical virus
made only of protein with NO DNA or RNA
cause destruction of the brain
e.g. BSE (mad cow disease)
48
viral diseases-respiratory tract
influenza (changes its surface proteins often so it avoids the immune response and can infect you repeatedly) and the common cold
49
viral diseases-skin
chicken pox, shingles, measles, rubella, warts, herpes
50
viral diseases-digestive tract
hepatitis, mumps, gastroenteritis
51
viral diseases-nervous system
rabies, polio, encephalitis
| can also cause mononucleosis, HIV, and viral fevers (e.g. yellow fever)
52
epidemiology
study of disease transmission
| can be transmitted by contact, respiratory, enteric, environmental, or vectors
53
pathogens
disease causing microbes
54
zoonoses
pathogens that come from animals
55
nosocomial infections
hospital acquired infections
56
normal flora
the microbes that live in and on certain areas of the human body normally and are not harmful
they are beneficial
57
exotoxins
secreted by certain bacteria
58
endotoxins
part of the cell wall of gram - bacteria
59
physical methods of controlling microbes & infections
heat- denatures proteins (boiling, autoclaving)
ionizing radiation- create toxic free radicals inside cells (x-rays and gamma rays)
UV radiation- damages DNA
60
chemical methods of controlling microbes & infections
most chemicals denature proteins
e.g. alcohol, iodine, chlorine, and phenolics
hydrogen peroxide most effective against anaerobic bacteria
61
antibacterial drugs
inhibit PG synthesis and damage cell wall (e.g. penicillins, cephalosporins, and bacitracin) and are most effective against gram + bacteria and those that interfere with protein synthesis (e.g. tetracycline, erythromycin)
sulfa drugs- block DNA and RNA synthesis by mimicking enzyme substrates
62
antiviral drugs
resemble nucleotides and block DNA synthesis
| e.g. acyclovir and AZT
63
antifungal drugs
target plasma membrane of fungi
| e.g. polyenes and azoles
64
immunology
protection against disease
| include the blood and certain organs
65
leukocytes (WBCs)
neutrophils, eosinophils, basophils, lymphocytes, and monocytes
66
neutrophils
most abundant type
phagocytic
protects mainly against bacteria
67
eosinophils
contain toxic granules
| protect against parasites
68
basophils
contain granules full of histamine and other mediators that cause inflammation
69
lymphocytes
T & B cells involved in specific immunity
| NK cells involved in nonspecific immunity
70
monocytes
can do phagocytosis or kill infected cells
| leave the blood stream and become macrophages or dendritic cells
71
plasma
fluid portion of blood
| contains antibodies and complement (which triggers inflammation)
72
lymph nodes
found in a network throughout the body
each protects a particular area or region of tissue
acts as a site for interaction between various cells of the immune system and foreign material (antigen)
73
thymus
where T cells mature
74
spleen
```
function similar to lymph notes except it protects the blood stream instead of tissues
involved in removing old RBCs
```
75
bone marrow
site where all blood cells are made (with both WBCs and RBCs)
76
nonspecific defense barriers
first line of defense
| skin, mucus lining of respiratory and GI tracts, and stomach acid
77
nonspecific defense mechanisms
```
second line of defense
includes phagocytosis (ingestion and destruction of bacteria and other materials), inflammation (protects against infection and repairs damage), fever (inhibits viral and bacterial replication), and interferons (blocks viral replication
```
78
inflammation
key mechanism for tissue repair
increases in blood vessel diameter and permeability
increased blood flow to the inflamed area
deposit fluid in the inflamed area
trigger a migration of phagocytes out of the circulation to destroy any invading bacteria
79
specific defenses
third line of defense
involves recognition and memory
response is stronger when immune system is re-exposed to a particular material
antigens-substances that the specific response recognizes and reacts to
involves T-cells and B-cells
80
T-cells
carry out cell-mediated response
produce cytokines- signalling molecules
protect against viral, fungal, and parasitic infections
81
helper T-cells
CD4
| activate other T cells, B cells, macrophages, and NK cells
82
suppressor T-cells
shut down other cells
83
cytotoxic T-cells
CD8
| kill virus-infected or cancer cells by binding to them and exposing them to toxins and perforins
84
NK cells
kill virus-infected or cancer cells, but do so nonspecifically
85
B-cells
```
produce antibodies (immunoglobulins) that bind specifically to antigens
protect against bacterial and viral infections
```
86
IgA
protects mucous membranes
| respiratory and digestive tract
87
IgG
most common in serum
| protects against toxins and can cross the placenta
88
IgD
on the surface of B cells
89
IgE
on the surface of mast cells and basophils and protects against parasitic infections
involved in allergies such as hay fever and food allergies
90
IgM
largest
| mainly in the blood stream
91
self recognition
immune system recognizes things that belong in the body
only attacks those that don't belong in the body
autoimmunity-immune system attacks itself
92
nonself recognition
immune system recognizes things that don't belong in the body
attacks these
93
autoimmunity
type of immune disorder where the immune system attacks and damages some part of the body
e.g. rheumatoid arthritis, lupus erythematosus, Graves disease
94
hypersensitivity
type of immune disorder where the immune system responds to a harmless material and that reaction causes death or damage to some part of the body
e.g. hay fever, asthma, hives, food allergies, Rh disease, and contact dermatitis
95
immunodeficiency
type of immune disorder where some part of the immune system is missing or does not work
result is recurrent infections
can be genetic or caused by outside factors such as malnutrition or infection
