LP1 Microbiology Flashcards
1
Q
Bright Field Illumination
A
Illumination produced by the passage of visible light through the condenser of a light microscope. Light is concentrated on the specimen and transmitted through the specimen, Objects are seen against a light background.
2
Q
Total Magnification
A
Ocular Lens (i.e. 10X) x Objective Lens (i.e. 40X) = Total Magnification (10X x 40X= 400X)
3
Q
Parafocal
A
The ability to change from one objective to another with only minimal adjustments for focusing. Increases the efficiency of the microscope. (“Par” means equal)
4
Q
Transmission
A
Passage of light through an object.
5
Q
Adsorption
A
Light rays do not pass or bounce off of an object but are taken up by the object.
6
Q
Reflection
A
Light strikes an object and bounces back.
7
Q
Resolution
A
The ability to see objects as separate and discrete entities. Oil is added to 100X objective lenses to improve clarity.
8
Q
Refraction
A
The bending of light as it passes through different media. (i.e. Lens-glass slide-specimen-air) Causes a blurred image as light bends clarity is lost.
9
Q
Fine Adjustment
A
Changes the distance between the objective lens and the specimen with small motor movements, aids in focusing the specimen.
10
Q
Arm
A
Part of the microscope that you grab to move while supporting the bottom of the microscope.
11
Q
Course Adjustment
A
Changes the distance between the objective lens and the sample with large motor movements, aids in focusing the specimen.
12
Q
On/Off switch
A
Turns the light source on or off.
13
Q
Nose piece
A
What holds the objective lenses
14
Q
Eyepiece
A
Ocular lens
15
Q
Objective lens
A
Magnifies the image before it passes through the body- tube to the ocular lens in the eyepiece.
16
Q
Diopter Adjustment
A
Adjustment on the eyepiece/ocular lens
17
Q
Joseph Lister
A
“Father of Antiseptic Surgery”. Initiated the use of Carbolid Acid (Phenol) to reduce infections during surgical procedures. Phenol is harmful to living cells.
18
Q
Obligate Aerobe
A
A bacterium that must have free oxygen to grow.
19
Q
DNA base pairs
A
Complementary base pairing ensures the accurate coding and decoding of cell information. Deoxynucleic Acid (DNA) pairs are Adenine (A)-Thymine (T), and Guanine (G) -Cytosine (C). Carries genetic information.
20
Q
Plasmid
A
Also called extrachromosomal DNA; a small circular independently replicating piece of DNA in a cell that is not part of its chromosome and can be transferred to another cell.
21
Q
Cytoplasm
A
Semi-fluid substances that supports organelles, site of chemical reactions in the cell.
22
Q
Conjugation
A
The transfer of genetic information from one bacterial cell to another by means of conjugation pili.
23
Q
Cell membrane/plasma membrane
A
Semi-permeable membrane regulating what goes in and out of the cell.
24
Q
cell wall
A
Maintains the shape of the cell, prevents cell from busting when fluids flow into the cell via osmosis, based on molecular structure retains the stains during staining procedures.
25
transduction
The transfer of genetic material from one bacterium to another by a macrophage.
26
transformation
A change in an organism's characteristics through the transfer of naked DNA.
27
transfer RNA
Carries the anti-codon for specific amino acids
28
Messenger RNA
Carries the message in the form of a codon for specific amino acids
29
Ribosomal RNA
Site of protein synthesis
30
Eukaryotic cell
A cell that has a distinct cell nucleus and other membrane-bound structures.
31
base
The part of a microscope that sits on a table or bench.
32
light source
The part of the microscope that illuminates samples.
33
iris diaphram
The part of the microscope that controls the amount of light on a sample.
34
condensor
The part of the microscope that collects and concentrates the light that illuminates the sample.
35
stage
The part of the microscope that the slide sits on.
36
slide holder
The part of the microscope that holds the slide. Clips.
37
Thayer-Martin Agar
A solid media that selects for pathogenic strains of the genus Neisseria.
38
Selective media
Selective media selects for certain bacteria while inhibiting the growth of other microorganisms.
39
Differential media
Differentiates between different organisms based on a macroscopic characteristics (i.e. sugar fermenting, pH color change, etc.)
40
MacConkey Agar
A solid media that selects for gram negative organisms and differentiates from lactose fermenting organisms.
41
MSA- Mannitol Salts Agar
A solid media that is selective for salt-loving microorganisms (halophiles) and differential (differentiate base of color of colony) for mannitol fermenting. (i.e. Staphylococcus aureus will grow but Serratia marcescens will not)
42
Agar
A polysaccharide extracted from certain marine algae and used to solidify medium
43
Agar slants
Solid agar in a test tube that is slanted as it cools. Allows for aerobic growth of microorganisms on the surface of the slant.
44
deep agar tubes
Solid agar in a test tube that is not slanted as it cools. Allows for anaerobic growth of microorganisms in the butt of the tube.
45
Prokaryotic cell
Microorganisms that lack a cell nucleus and membrane-enclosed internal structures; all bacteria in the Kingdom Monera (Prokaryotae) are prokaryotes. Characteristic shape/arrangement (i.e. Rods and cocci in chains or clusters).
46
India Ink stain
A special negative staining method (no color) which identifies the production of capsules which appear as halos. (i.e. Cryptococcus neoformis)
47
Streak plate
A way of streaking bacteria out on a agar plate in four quadrants to isolate a single colony. Used to isolate aerobic bacteria that will grow on the surface.
48
Trichophyton species
Trichophyton fungi are molds characterized by the development of both smooth-walled macro- and microconidia.
Trichophyton is a genus of fungi, which includes the parasitic varieties that cause tinea, including athlete's foot, ringworm, jock itch, and similar infections of the nail, beard, skin and scalp.
49
Candida species
A gram positive large oval yeast that reproduces by budding. Candida is yeast, a type of fungus, that that is typically found in small amounts on your mouth, skin and in your intestines. Candida can cause infections such as thrush, vaginal yeast infections and skin/nails called Candidiasis.
50
Staphylococcus aureus
A gram positive cocci that is arranged in grape like clusters. S. aureus has long been recognized as one of the most important bacteria that cause disease in humans. It is the leading cause of skin and soft tissue infections such as abscesses (boils), furuncles, and cellulitis. S. aureus can also cause gastrointestinal illness (food poisoning) from the toxins that they produce.
51
Fungi (pl.) or Fungus (sl.)
The kingdom of non-photosynthetic, eukaryotic organisms that absorb nutrients from their environment. Most are saprophytic.
52
Endospore stain
A special stain used to identify endospores (dormant structures) in bacterial cells.
53
Acid Fast Stain
A differential stain that differentiates between Mycobacterium species and non-Mycobacterium species. Acid Fast Bacteria positive (red bacteria) is Mycobacterium species. Acid Fast negative (green-blue) is non-Mycobacterium.
54
Gram Stain
A differential stain for stain that reveals preliminary ID, diagnostic and treatment strategies. Procedure is Primary stain (Crystal Violet-60 sec.), Mordant (Iodine-60 sec.), Decolorizer (Acetone-alcohol-30 sec.) and Counter stain (Sarfarin-60 sec.). Blue/Purple bacteria- gram positive and Red bacteria- gram negative. Mycobacterium does not gram stain- use acid fast stain.
55
Hanging Drop Prep
Using a young broth culture place a drop of broth on a concave slide, cover with a cover slip and use petroleum jelly to prevent drying. Viewing this living culture can confirm mobility.
56
Bacteria
All prokaryotic microorganisms.
57
Pour plate
A pour plate is used to incorporate bacteria within the media (less oxygen). 1ml of liquid bacterial suspension is added to a petri plate- pour about 15 mls of warm (not hot) agar media on plate and swirl. Let sit to harden then incubate.
58
Binary fission
A form of reproduction where in prokaryotes the bacteria cell duplicates its components and splits into two daughter cells.
59
Mitosis
The cell nucleus in eukaryotic cells divides to form an identical daughter cell.
60
Meiosis
Division process in eukaryotic cells that reduce the chromosome number in half.
61
decline phase (death phase)
The last section of the growth curve when the number of living cells decrease and endospores form.
62
stationary phase
The third section of the growth curve, where growth plateaus. The number of new cells equal to the number of dying cells. Cells are running out of nutrients and oxygen and waste products are accumulating.
63
log phase
The second section of the growth curve, where cells are multiplying rapidly and generation time can be calculated.
64
lag phase
The first section of the growth curve, where the cells are using their metabolic pathways to produce and store energy. Length of this section depends on the availability of nutrients- cells do not increase in number or size.
65
fermentation
A metabolic pathway that is performed by facultative aerobes, facultative anaerobes and obligate anaerobes. Pyruvic Acid-acid/alcohol or gas. Produces 2 ATP. Used in wine, beer, cheese, bread and sauerkraut production.
66
aerobic respiration
Process in which aerobic organisms gain energy from the catabolism of organic molecules via the Krebs cycle and oxidative phosphorylation. Produces 38 ATP
67
glycolysis
A metabolic pathway used by both aerobic and anaerobic bacteria. Simple sugar-glycolysis-pyruvic acid. Produces 2 ATP
68
facultative anaerobe
A bacterium that carries on aerobic metabolism when oxygen is present but shifts to anaerobic metabolism when oxygen is absent.
69
Selman Waksman
Worked with soil microbes. Developed a group of drugs as "antibiotics" to treat bacterial infections. Initiated the use of Streptomycin, neomycin, chloramphenicol, chlortetracycline.
70
Alexander Fleming
Discovered "lysozyme" an enzyme found in tears, saliva and sweat that has antimicrobial capabilities. Observed penicillin growing on plates inhibited the growth of bacteria and noted its potential to treat bacterial infections (1928).
71
Paul Ehrlich
Credited with the first serious attempt on "chemotherapy" to eradicate infections. Practical treatment for Syphilis (1909). Developed the precursor to the Gram Stain.
72
wet mount
Allow observers to view organisms in a living state and confirms their motility. (i.e. Hanging Drop Preps and KOH Prep)
73
KOH prep
Allows the observer to view samples for fungal elements. Procedure: Sample of hair, skin, nail are mixed with 10% Potassium Hydroxide (KOH). KOH dissolves the protein in the sample leaving the fungal elements intact for viewing.
74
Electron Microscope
Uses a beam of electrons instead of light or electromagnets instead of lens to view objects. Scattering electrons by atoms travel through a vacuum to avoid a distorted picture. Detailed images appear as three-dimensional pictures.
75
Fluorescence Microscope
The light source is ultraviolet which causes the release of light with a longer wavelength. Different wavelengths produce brilliant colors of yellow, orange or green, Special stains with fluorescent dyes are used to highlight certain organisms.
76
Dark field Microscopy
Light is reflected off the specimen at an angle by a dark field condenser. Objects are seen white against a dark background. Use to stain organisms with poor staining ability (i.e. Treponema pallidum that causes syphilis)
77
Obligate Anaerobe
A bacterium that is killed by free oxygen. Obligate anaerobes may use fermentation or anaerobic respiration. Instead of oxygen, they use sulfate, nitrate, iron, manganese, mercury, or carbon monoxide as electron acceptors for respiration. The energy yield is lower than that in aerobic respiration. Example: Clostridium sp.
78
Phillip Semmelweis
1840's Vienna General Hospital (Austria) Medical Director. Identified the connection between autopsies and infections. Recognized the need for aseptic techniques (hand washing), but was unable to convince his colleagues of that importance.
79
Robert Koch
Worked with the bacterium that causes anthrax and was able to grow the organism as pure culture (a culture that contains only one organism). Disputed the Spontaneous Generation theory supporting one organism-one disease concept. Formulate the 4 postulates: 1) Specific organism always associated with a certain disease 2) Isolate organism in a pure culture 3) Culture will cause disease to a healthy animal 4) Same organism can be isolated from ill animal. 1876 Anthrax, 1882 TB, 1883 Vibrio cholerea
80
Louis Pasteur
Worked with swan-necked flasks to disprove the theory of Spontaneous generation. Developed the process of pasteurization to inhibit microbial growth. Contributed to the development of vaccines and its credited with the development of the Rabies vaccine.
81
Germ theory
The theory that supports the concept that microorganisms or germs invade other living things and can cause disease. Current theory we observe today.
82
Spontaneous generation
The theory that supports the concept that microorganisms can arise from non-living things.
83
slime layer
Less tightly bound and thinner protective structure found outside the cell wall. Used to trap nutrients and aids in attachment of the cell to various surfaces.
84
capsule
Thick and tightly bound protein structure found outside the cell wall used for protection.
85
pili
2 types: 1) Attachment pili attach bacterial cells to various surfaces, 2) Conjugation pili are involved with the transfer of genetic material between cells.
86
axial filaments
Organ of motility. attached to the bacterial cell and does NOT extend off the cell.
87
flagella
Oran of motility. Attached to the cell membrane and extends of the bacterial cell.
88
Anton Leeuwenhock
Credited with the development of lenses used to observe very small living "animalcules" which were later identified as bacteria, protozoa, algae, yeast and other fungi. 1674
89
Streptococci species
A bacteria that is a gram positive, cocci in chains. Five strains cause disease in humans; These include: Group A—beta-hemolytic, S. pyogenes; Group B—beta hemolytic, S. agalactiae; Group C—beta-hemolytic; Group D—Enterococcus; and, Group F—alpha-hemolytic, S. viridans.
90
Escherichia coli (E. coli)
Gram negative rods in chains. Escherichia coli (E. coli) bacteria normally live in the intestines of healthy people and animals. Most types of E. coli are harmless or cause relatively brief diarrhea. But a few strains, such as E. coli O157:H7, can cause severe stomach cramps, bloody diarrhea and vomiting. MacConkey agar used.
91
Rhinovirus
A RNA virus from the Picornviridae family that can cause upper respiratory infections and is transmitted via respiratory secretions.
92
Taenia species
A Helminth-Cestode-Platyhelminth (tapeworm) that causes Taeniasis infections from ingesting undercooked beef, or pork. >165 F
93
Enterobius vermicularis
A Helminth- Nematode (roundworm) that causes Enterobiasis, It is widely known as the human pinworm due to the female’s long, pointed tail.
94
parasites
An organism that lives at the expense of another living organism. Includes protozoa, helminths and arthropods, Invade specific tissues, can produce a wide range of clinical symptoms that mimic many infectious diseases and are diagnosed by ID in patient's specimens.
95
viruses
An acellular (lack cellular components), contain only one nucleic acid (DNA or RNA), do not replicate or carry out metabolic processes. Viruses are Obligate Intracellular Parasites.
96
endospore (spores)
Are dormant structures of the Clostridium (sp.) and Bacillus (sp.). Formed when adverse environmental conditions occur. Do not replicate or carry out metabolic processes. Resiliant and resist destruction from disinfection, antimicrobial therapy and human defense mechanisms.
97
nuclear region
Also called the nucleoid, central location of DNA, RNA, and some proteins in bacteria; not a true nucleus.
98
ribosome
Site for protein synthesis consisting of RNA and protein, located in the cytoplasm.
99
RNA base pairs
Nucleic acids that carries information from DNA to the sites where proteins are manufactured in cells and that directs and participates in the assembly of proteins. Ribonucleic Acid (RNA) pairs are Adenine (A)-Uracil (U), and Guanine (G)-Cytosine (C).
100
DNA base pairs
Two complementary DNA nucleotide bases join to form a DNA double helix. Base pairs are Adenine (A)-Tyrosine (T) and Guanine (G)-Cytosine (C).
