1
Q
What does facultative anaerobic mean?
A
The microorganism grows best with oxygen but can grow without.
2
Q
Define Vector.
A
An organism that does not cause disease itself but which spreads infection by conveying pathogens from one host to another.
3
Q
Define host, primary host, and secondary host.
A
Host - a living cell in which a virus reproduces.
Primary host - (definitive host) a host in which the parasite reaches maturity and, if possible, reproduces sexually
Secondary host - (reservoir host) can harbor a pathogen indefinitely with no ill effects.
4
Q
Define microbiology
A
the study of microorganisms at a microscopic level.
The study of microorganisms - those organisms that exist in nature as single cells.
5
Q
What are Thomas Brock’s characteristics of life (5)?
A
- Self-feeding or nutrition
- Self-replication
- Differentiation
- Chemical signaling
- Evolution
6
Q
What was the Black Plague?
A
a pandemic that killed 1 out of 3 people in the 1330’s
7
Q
What is the bacteria associated with the Black Plague?
A
Yersenia pestis
8
Q
Black Plague: Vector? Primary Host? Secondary Host (Reservoir)?
A
Vector - fleas
Primary host - humans
Secondary host - goring rats
9
Q
What factors played a role in the spread of the Black Plague?
A
Caused by unsanitary conditions and spread by the large quantity of rats as well as people traveling for trade throughout Europe.
10
Q
Describe the state of the Black Plague: The Infection
A
- infection of the lymphatic system
- caused by infected fleas often found on rats and mice
- Bacteria found within infected fleas gut results in the regurgitation of ingested blood now infected by the bacteria
- blood transferred into the new host by the fleas next bite
- rapidly spreads into lymph nodes which causes them to hemorrhage and become swollen
11
Q
Describe the state of the Black Plague: The Symptoms (12)
A
- chills
- high fever (102)
- muscle pain
- severe headache
- malaise (general ill feeling)
- seizures
- gastrointestinal problems
- heavy breathing
- blood vomiting
- urination of blood
- lymph swelling
- lenticulae (black dots scattered throughout the body)
12
Q
Describe the state of the Black Plague: The Diagnosis
A
- physical examination
- lab tests (sample of blood or sputum)
- rule out other diseases commonly confused with the plague (typhoid fever, cat scratch fever, hernia, syphilis, shigellosis, appendicitus, etc)
13
Q
Describe the state of the Black Plague: The Treatment
A
- Antibiotics: Gentamicin, Streptomycin, Choloramphenicol, Tetracycline
14
Q
What are the four categories of Microorganisms and an example of each?
What are the three routes of exposure?
A
Categories: 1. Virus - HIV 2. Bacteria - E. coli 3. Fungi - Penicillan mold 4. Protists - Amoeba Routes of exposure: 1. Ingestion 2. Injection 3. Inhalation
15
Q
What are the characteristics of bacteria?
A
- Prokaryotes
- Peptidoglycan cell walls
- Binary fission (asexual reproduction; “division in half”)
- Use organic chemicals, inorganic chemicals, or photosynthesis for energy
16
Q
What are the characteristics of fungi?
A
- *Eukaryotes
- Chitin cell walls (a tough, semitransparent substance)
- Use organic chemicals for energy
- Molds and mushrooms are multicellular
- Yeasts are unicellular
- *Aerobic or facultatively anaerobic
- *Chemoheterotrophic (great decomposers)
- *Saprotrophic (absorb their food rather than ingest it)
- *At a cellular level they are VERY similar to humans
- *Mycology is the study of fungi
17
Q
What are the characteristics of a virus?
A
(Viruses are NOT living organisms)
- Acellular
- Consist of DNA or RNA
- Core is surrounded by a protein coat
- Coat may be enclosed in a lipid envelope
- Viruses are replicated only when they are in a living host cell (“cellular parasite”)
18
Q
What are the characteristics of Protozoa?
A
- Eukaryotic
- Unicellular
- Chemoheterotrophs (decomposer)
- Asexual reproduction by fission or budding
- Sexual reproduction by conjugation
- Vegetative form is a trophozoite
- Some produce cysts
19
Q
How do you name microorganisms?
A
Each organism has two names: the genus and specific epithat (species). The genus is always capitalized and the species is lower case.
20
Q
Put the following in order from smallest to largest:
Prokaryotic Cells
Eukaryotic Cells
Viruses
A
Viruses - smallest
Prokaryotic Cells - medium
Eukaryotic Cells - largest
21
Q
What is the relative size of a Prokaryotic cell?
A
1-10um
22
Q
What is the relative size of a Eukaryotic cell?
A
10-100um
23
Q
What is a Prokaryote?
List 5 characteristics.
A
“Tiny and simple”
A single-celled form of life without internal membrane bound organelles known as a nucleus. They are thought to be the oldest (primitive) forms of life on earth predating the eukaryotes.
1. One circular chromosome, not in a membrane
2. No histones
3. No organelles
4. Peptidoyglycan cell walls
5. Binary fission
24
Q
What is a Eukaryote?
List 5 characteristics.
A
“Large with compartments”
Organisms with large cells and internal membrane bound structures called organelles (the defining one being the nucleus).
1. Paired chromosomes in nuclear membrane
2. Histones
3. Organelles
4. Polysaccharide cell walls
5. Mitotic spindle
25
List the main parts of a Prokaryote.
- Nucleoid
- Capsule
- Ribosomes
- Cell Wall
- Cell membrane
- Flagellum
26
List the main parts of a Eukaryote.
- Nucleolis
- Nucleus
- Mitochondria
- Endoplasmic Reticulum
- Ribosomes
27
What is the definition of a virus and why are they not considered to be alive?
an infective agent that typically consists of a nucleic acid molecule in a protein coat, is too small to be seen by light microscopy, and is able to multiply only within the living cells of a host.
They are not considered to be alive because they do not grow, have homeostasis, or metabolize.
(example small pox)
28
Define the Central Dogma of molecular Biology?
It is the process by which the instructions in DNA are converted into a functional product. ("the flow of information in a cell")
29
Explain the Central Dogma process.
The central dogma describes a two step process, transcription and translation by which the information in genes flows into proteins. (DNA - mRNA - Protein)
Transcription is the first step of gene expression, in which a particular segment of DNA is copied into RNA (mRNA) by the enzyme RNA polymerase.
Translation is the process in which cellular ribosomes create proteins. In translation, messenger RNA (mRNA) is decoded by a ribosome to produce a specific amino acid chain, or polypeptide.
30
milli =
thousandths
31
micro =
millionth
32
nano =
billionth
33
Define atom.
the smallest unit of matter that enters into chemical reactions. (they interact to form molecules)
34
Electron
negatively charged particle
35
Proton
positively charged particle
36
Neutron
uncharged particle
37
Molecular weight
the sum of the atomic weights in a molcule
38
Mole
a substances molecular weight in grams.
39
Anabolism
the synthesis of molecules in a cell
| Synthesis reaction: A + B -> AB Anabolic Pathway
40
Catabolism
the decomposition reactions in a cell
| Decomposition reaction: AB -> A + B Catabolic Pathway
41
Solvent
a substance that dissolves a solute (a chemically distinct liquid, solid or gas), resulting in a solution. A solvent is usually a liquid but can also be a solid or a gas.
42
Acid
a substance that dissociates into one or more H+.
| ex. HCl -> H+ + Cl-
43
Base
a substance that dissociates into one or more OH-
| ex. NaOH -> Na+ + OH-
44
How is the amount of H+ in a solution expressed?
as pH
| (pH = -log[H+]
45
What will increasing [H+] do?
increase the acidity
46
What will increasing the [OH-] do?
increase the alkalinity
47
What pH do most organisms grow best at?
between pH 6.5 and 8.5
48
The log scale goes up to what number? which part is acidic and which part is alkaline?
Scale goes from 1 to 14
1-6 acidic
8-14 alkaline
7 neutral
49
What are the 4 classes of macromolecules of a cell?
1. Carbohydrates
2. lipids
3. nucleic acids
4. proteins
50
What are carbohydrates?
Biological molecules consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1
(the sugars, starches and fibers found in fruits, grains, vegetables and milk products.)
Other names: Oligosaccharides, polysaccharides, monosaccharides, starch, glycogen, dextran, celluose, chitin
51
What are lipids and what is special about them?
A group of naturally occurring molecules that include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E, and K), monoglycerides, diglycerides, triglycerides, phospholipids, and others.
- Only one of the group that are non-polar
- not soluble in water
- primary components of cell membrane
- consists of C, H, and O
52
What is a nucleic acid?
A complex organic substance present in living cells, especially DNA or RNA, whose molecules consist of many nucleotides linked in a long chain.
53
What do nucleotides consist of?
- pentose
- phosphate group
- nitrogen-containing (purine or pyrimidine) base
54
What are proteins? List some important facts about proteins.
Large biomolecules, or macromolecules, consisting of one or more long chains of amino acid residues. (comprised of 20 amino acids)
- MOST IMPORTANT
- Enzymes are proteins that speed chemical reactions
- Transporter proteins move chemicals across membranes
- Flagella are made of proteins
- Some bacterial toxins are proteins
55
What are the primary, secondary, and tertiary structures of proteins?
Primary structure - polypeptide chain
Secondary structure - helix and pleated sheets
Tertiary structure - folded helix
56
What are the characteristics of DNA?
- has deoxyribose
- double helix
- A (Adenine) hydrogen bonds with T (Thymine)
- C (Cytosine) bonds with G (Guanine)
57
What are the characteristics of RNA?
- has ribose
- single stranded
- A (Adenine) bonds with U (Uracil)
- C (Cytosine) bonds with G (Guanine)
58
How does one go about classifying microorganisms?
A. Morphology (size, shape, etc)
B. Staining pattern (ie. Gram staining)
C. Growth on selectable media (biochemical tests)
D. Classification using PCR (Polymerase Chain Reaction) (ie. genotyping)
59
What is the main difference between acidic and basic dye?
In basic dye the chromophore is a cation, in acidic dye the chromophore is an anion.
60
What is the catalase test?
The catalase test is used to differentiate staphylococci (catalase-positive) from streptococci (catalase-negative). The enzyme, catalase, is produced by bacteria that respire using oxygen, and protects them from the toxic by-products of oxygen metabolism.
61
What is the Coagulase test?
A test that differentiates between pathogenic and non-pathogenic strains of Staphylococcus. (Bacteria that produce coagulase use it as a defense mechanism by clotting the areas of plasma around them, thereby enabling themselves to resist phagocytosis by the host's immune system.
62
What is an endospore?
microbial adaption to extreme environmental conditions.
63
Name some Gram-positive bacterial examples, describe their morphology, and the infection associated with each. (4)
1. Staphylococci - clustered spheres, species: aureus (skin) Boils, impetigo, food poisoning, cellulitis, and toxic shock syndrome are all examples of diseases that can be caused by Staphylococcus.
2. Streptococci - chain-like spheres, pathogenic species, hemolytic (can lyse blood cells), found in mouth, nares, pharynx - Can cause many disorders, including pharyngitis, pneumonia, wound and skin infections, sepsis, and endocarditis.
3. Enterococcus - paired spheres, falcultative anaerobes, fermentative metabolism (can ferment carbs), some are hemolytic, found in mucosal surfaces - Can cause a variety of nosocomial infections of which urinary tract infections are the most common.
4. Clostridium - rod-shaped, produce endospores, obligate fermenters, cytolysins, anaerobe, found in soil - One of the most serious causes of antibiotic-associated diarrhea.
64
Name 3 species of Clostridium and what they do.
1. tetanus toxin - blocks the release of neurotransmitters
2. botulinum - blocks the presynaptic release of the neurotransmitter acetylcholine
3. perfringens - attacks cell membranes causing extensive tissue damage and necrosis
65
What is the major group of Gram-negative bacteria?
Proteobacteria
66
Name some Gram-negaitve bacterial examples and their morphology. (5)
1. Escherichia coli - Gram negative, aerobic, rod-shaped, cannot sporulate, prefer higher temps, found in lg. intestines - The most frequent causes of many common bacterial infections, including cholecystitis, bacteremia, cholangitis, urinary tract infection (UTI), and traveler's diarrhea, and other clinical infections such as neonatal meningitis and pneumonia.
2. Salmonella - Gram negative, motile and produce hydrogen sulfide, many cannot ferment lactose, non spore forming, transmitted through ingestion of contaminated food and water - Causes typhoid fever, food poisoning, gastroenteritis, enteric fever and other illnesses.
3. Pseudomonas - Gram negative, facultative anaerobe, rod-shaped, motile, non-spore forming, catalse + and oxidase + - Frequent cause of nosocomial infections such as pneumonia, urinary tract infections (UTIs), and bacteremia.
4. Moraxella - Gram negative, short rods, coccobacilli, or diplococci, oxidase + and catalse +, linked to respiratory tract infections (causes bronchitis and pneumonia in children and adults with underlying chronic lung disease and is occasionally a cause of bacteremia and meningitis, especially in immunocompromised persons.)
5. Helicobacter - Gram negative, human pathogen H. pylori, responsible for peptic ulcers, microaerophilic, fast-moving, found in lining of the upper gastrointestinal tract - Causes atrophic and even metaplastic changes in the stomach, and it has a known association with peptic ulcer disease.
67
Give some examples of common bacterial infections:
- Steptococcus pneumonia (bacterial meningitis, pneumonia, sinusitis)
- Mycobacterium tuberculosis (tuberculosis)
- Staphylococcus aureus (skin and eye infections)
- Helicobacter pylori (gastritis)
- Campylobacter jejuni (food poisoning)
- Salmonella typhimurium (food poisoning)
- Clostridium difficile (food poisoning)
- Escherichia coli (urinary tract infections, food poisoning)
- Yersinia pestis (bubonic plague)
68
Name, describe and tell the function of the 4 microbial adaptations:
1. Glycocalyx - found in pseudomonas, uniform capsule prevents phagocytosis, irregular slime layer, extracellular polysaccharide allows cell to attach
2. Endospores - resistant to desiccation, heat, chemicals; found in the genera Bacillus and Clostridium, resistant, thick-walled
3. Flagella - used to propel itself through environment
4. Cell Wall - made up of peptidoglycan, structural support/osmotic stress
69
What is the function of the plasma membrane?
the phospholipid bilayer provides selective permeability allowing passage of some molecules.
70
Simple diffusion
movement from high concentration to low concentration
71
Facilitative diffusion
solute combines with a transporter protein in the membrane
72
Active transport
movement from low to high concentration (against gradient) which requires ATP and transporter protein to move across barrier
73
Osmosis
movement of water across a semipermeable membrane (high to low concentration)
74
Osmotic pressure
the pressure needed to stop the movement of water across the membrane
75
Isotonic
(isosmotic) no net movement of water
76
Hypotonic
(hypoosmotic) water moves into the cell (lysis)
77
Hypertonic
(hyperosmotic) water moves out of the cell (plasmolysis)
78
List the organelles in eukaryotic cells.
- cytoplasm
- ribosomes
- nucleus
- endoplasmic reticulum
- golgi apparatus
- mitochondria
- lysosomes
79
What is endocytosis? Phagocytosis? Pinocytosis?
Endocytosis - a form of active transport in which a cell transports molecules (such as proteins) into the cell (endo- + cytosis) by engulfing them in an energy-using process.
Phagocytosis - ingestion of bacteria
Pinocytosis - ingestion of liquid into a cell
80
List the 5 divisions of fungi and give an example.
1. Chytridiomycota - "chytrids" (usually not a human pathogen) Ex. Batrachochytrium dendrobatidis (skin cancer)
2. Zygomycota - "zygote fungi" (usually not a human pathogen) Ex. Rhizopus oligosporus (flesh eating nose)
3. Ascomycota - "sac fungi" (pathogenic fungi which include the following: trychophyton, Aspergillus, Blastomyces, Candida albicans and Histoplasma capsulatum) Ex. Saccharomyces cerevisiae (yeast)
4. Basidiomycota - "club fungi" (pathogenic and toxic fungi which include the following: Cryptococcus, Amanita and Claviceps) Ex. Boletales (mushrooms)
5. Deuteromycota - Catch all category for unclassified fungi. Ex. Pneumocystis carinii (pneumonia in AIDS patients)
81
List the 4 pathogenic fungi.
1. Candida
2. cryptococcus neoformans
3. Histoplasma capsulatum
4. ringworm
82
What is ringworm?
a parasitic fungi that grows on the outer layers of skin; thrives best on skin that is moist, hot and away from sunlight.
83
What are the 5 divisions of protozoa?
1. Plasmodium - causes malaria (vector born - mosquito)
2. Giardia lamblia - no mitochondria; multiple flagella; can occur from consuming contaminated food or water.
3. Amoebas - obtains its food through phagocytosis; includes one or more nuclei and a simple contractile vacuole to maintain osmotic pressure; Causes Ameboid dysentery that results in severe diarrhea containing mucus and blood in the feces.
4. Cryptosporidium - cause of the most common water borne diseases in the U.S; can form cysts while residing in the gastro intestinal tract
5. Euglenozoa - moved by flagella; chemoheterotrophs; includes trypanosoma which cause sleeping sickness (tse-tse flies act as vector)
84
What is the life cycle of plasmodium?
- Sporozoites from the saliva of a biting female mosquito are transmitted to either the blood or the lymphatic system of the recipient.
- Sporozoites then then migrate to the liver and invade hepatocytes. (remain for 9-16 days)
- return to the blood and penetrate RBC's where they produce merozoites which reinfect the liver or micro and macrogametocytes.
- Another mosquito feeds on the blood and sucks the gametocytes into its gut where exflagellation of microgametocytes occurs and they are fertilized.
- Results in ookinete which penetrates the wall of a cell and develops into an oocyst.
- Sporogeny with the oocyst produce many sporozoites and, when the cyst ruptures, migrate to the salivary gland for injection into another host.
85
What are the characteristics of Helminths (worms)?
- Eukaryotic
- multicellular animals that usually have digestive, circulatory, nervous, excretory, and reproductive systems.
- bilateral symmetry
- parasitic (absorb nutrients from host's food)
86
What are the two main groups (phyla) of Helminths?
1. Platyhelminths (flatworms)
| 2. Nematoda (roundworms)
87
What are two types of Platyhelminths (flatworms)?
1. Trematodes or Flukes - "Blood Fluke"; Live in waters contaminated with feces, burrow through skin of human and enter the circulatory system, particularly abdominal and pelvic veins.
2. Cestodes or Tapeworms - "Beef Tapeworm" (Taenia saginata)
88
What are two types of Nematodes (roundworms)?
1. Infectious eggs - pinworm (Enterobius vermicularis) and Ascaris (Ascaris lumbricoides)
2. Infectious larvae - Adult Hookworm (Necator americanus), Trichinosis (Trichinella spiralis) and Anisakines (Wriggly worms)
89
What does ELISA stand for and what is it used for?
An enzyme-linked immunosorbent assay, also called ELISA or EIA, is a test that detects and measures antibodies in your blood. This test can be used to determine if you have antibodies related to certain infectious conditions.
90
What does PCR stand for and what is it used for?
PCR stands for Polymerase Chain Reaction. It's a testing technique that can detect either DNA or RNA from any kind of organism, such as HIV, for example.
Microbiology
flashcards
Decks in class (21)
# Cards
-
Exam 1 Micro-Organisms15
-
Ex. 1-5; 1-618
-
Common bacteria18
-
Ex. 2-135
-
Ex. 4-311
-
Microscope24
-
Exam 190
-
Simple and Negative Staining22
-
Gram and Acid-Fast Staining24
-
Lab Practical 1 Additional Review110
-
Ex. 2-2; 2-321
-
Ex. 2-8; 2-9; 2-1239
-
Lab Exam 2: Ex. 4-1; 4-227
-
Exam 2140
-
Lab Exam 2: Ex. 4-4; 4-522
-
Lab Exam 2: Ex. 5-1; 5-2; 5-354
-
Lab Exam 2: Ex. 4-617
-
Lab Exam 2: Ex 5-4; 5-5; 5-7; 5-8; 5-9; 5-11; 5-12; 6-1; 9-560
-
Lab Exam 2: Microbes8
-
Lecture Exam 3180
-
Additional Flashcards for final38
