Exam #1 Study Guide/Review Flashcards
1
Q
What are the 3 domains?
A
Archaea, bacteria, eukaryota
2
Q
Who supported theory of spontaneous generation?
A
- Aristotle
- Jan Baptista van Helmont
- John Needham
3
Q
Who refuted theory of spontaneous generation?
A
- Francesco Redi
- Louis Pasteur
- Lazzaro Spallanzani
4
Q
Robert Koch’s 1st postulate
A
microorganism must be observed in every case of the disease
5
Q
Robert Koch’s 2nd postulate
A
microorganism must be isolated & grown in a pure culture
6
Q
Robert Koch’s 3rd postulate
A
the pure culture, when inoculated in animals, must reproduce the disease
7
Q
Robert Koch’s 4th postulate
A
microorganism must be recovered from diseased animal
8
Q
Structure & function of fimbriae
A
- short bristle like proteins projecting from cell surface by the 100s
- enable cell to attach to surfaces and other cells
9
Q
Structure & function of pili
A
- longer less numerous protein appendages
- aid in attachment to surfaces
- F pilus (sex pilus) transfers DNA between bacterial cells
10
Q
Structure & function of flagella
A
- used to move in aqueous environments
- stiff spiral filaments composed of flagellin protein subunits
- extend outward from cell and spin
- basal body is motor of flagellum and is embedded in plasma membrane
- hook region connects basal body to filament
11
Q
Host range
A
most viruses can only infect cells of one or a few species of organisms
12
Q
tropism
A
viruses only infect specific hosts and only specific cell types within those hosts
13
Q
Attachment
A
virus interacts with specific host cell receptors
14
Q
Penetration
A
animal viruses enter thru endocytosis or membrane fusion
15
Q
Uncoating
A
viral contents are released
16
Q
Biosynthesis
A
viral nucleic acid & proteins are synthesized
17
Q
Maturation
A
new mature virions assemble
18
Q
Release
A
released by lysis or budding
19
Q
Hippocrates
A
- father of western medicine
- didn’t believe that disease was caused by supernatural forces; believed it had natural causes
- Hippocratic oath
20
Q
Louis Pasteur
A
- Showed that individual microbe strainshad unique properties
- demonstrated that fermentation is caused by microbes
- invented pasteurization
- Developed vaccines
- performed swan neck flask experiment
21
Q
Robert Koch
A
- 1st to demonstrate connection between a single isolated microbe & a known human disease
- discovered bacteria that cause anthrax, cholera, & TB
22
Q
Franseco Redi
A
- van Helmont’s contemporary
- performed experiment that refuted idea that maggots spontaneously generate on meat
23
Q
Jan Baptista van Helmont
A
- Flemish scientist
- proposed that mice arose from rags & wheat kernels left in open container for 3 weeks
24
Q
Robert Hooke
A
While observing cork through his microscope, Hooke saw tiny boxlike cavities, which he illustrated and described as cells. He had discovered plant cells! Hooke’s discovery led to the understanding of cells as the smallest units of life—the foundation of cell theory.
25
Theodor Schwann
1st concluded that both plants and animals were composed of cells. 2nd, these cells have independent lives. 3rd, these independent lives are subject to the organism's
26
Robert Remak
published convincing evidence that cells are derived from other cells as a result of cell division
27
Rudolf Virchow
finding cells in bone and connective tissue and describing substances such as myelin
28
Robert Brown
best known for his descriptions of cell nuclei and of the continuous motion of minute particles in solution
29
Konstantin Mereschkowski
proposed symbiogenesis, or endosymbiotic theory.
30
Andreas Schimper
- established the fact that starch is both a source of stored energy for plants and a product of photosynthesis
- showed that starch grains are formed within certain bodies of the cells of plants; he named these bodies chloroplasts.
31
Lynn Margulis
argued that inherited variation, significant in evolution, does not come mainly from random mutations.
32
Girolamo Fracastoro
early proponent of germ theory of disease
33
Ignaz Semmelweis
- noted that mothers who gave birth in hospital ward died of puerperal fever after childbirth w/10%-20% mortality rate
- mothers in wards staffed w/midwives had 1% mortality rate
- medical students handled dead tissues & pts w/out washing hands
- recommended hand wash with chlorinated lime water before & after
- mortality rate decreased to 1%
34
John Snow
- conducted studies to track source of cholera outbreaks in London
- represents 1st known epidemiological study that resulted in public response to epidemic
35
Joseph Lister
- attempted to determine cause of post surgical infections
- began using carbolic acid (phenol) as disinfectant/antiseptic during surgery
- created aseptic technique
36
Marcus Terentius Varo
- 1st to propose concept that things we can't see cause disease
37
Thucydides
- Father of scientific history
- evidence based analysis of cause & effect reasoning
- made observation during Athenian plague that survivors didn’t get reinfected; immunity
38
Antone van Leeuwenhoek
- 1st to develop lens powerful enough to view microbes
- was able to observe organisms he called “animalcules”
39
Carolus Linnaeus
- Most famous early taxonomist
- created categorization above kingdom level
40
Matthias Schleiden
- cofounded cell theory w/Theodor Schwann
- defined cell as basic unit of plant structure
41
Dmitri Ivanovski
discovered filterable component smaller than bacterium that caused tobacco mosaic disease (TMD)
42
Martinus Beijerinck
determined component found by Ivanovski was not a bacterium but more like a chemical
43
Coccus shape
Round
44
Bacillus shape
Rod
45
Vibrio shape
Curved rod
46
Coccobacillus shape
Short rod
47
Spirillum shape
Spiral
48
Spirochete shape
Long, loose, helical spiral
49
Coccus arrangement
Single coccus
50
Diplococcus arrangement
Pair of cocci
51
Tetrad arrangement
Grouping of 4 cocci arranged in square
52
Streptococcus arrangement
Chain of cocci
53
Staphylococcus arrangement
Cluster of cocci
54
Bacillus arrangement
Single rod
55
Streptobacillus arrangement
Chain of rods
56
Structure & function of prokaryotic cell wall
- maintains cell shape, protects cell interior, prevents cell from bursting
- composed of peptidoglycan
57
Structure of prokaryotic ribosomes
- 70S ribosomes
- composed of 30 S & 50S subunit
58
How are viruses cultivated or cultured?
- in vivo (in a whole living organism, plant, or animal)
- in vitro (outside living organism in cells in an artificial environment)
- cannot survive w/out host
59
*Trichuris trichuria*
human whipworm
60
*Borrelia burgdorferi*
causes Lyme disease
61
*Piptoporus betulinus*
- fungus
- has laxative & antibiotic properties
62
*bacillus anthracis*
Bacteria that causes anthrax
63
*Vibrio cholera*
Bacteria that causes cholera
64
*mycobacterium tuberculosis*
Bacteria that causes tuberculosis
65
Ernest Haeckel
Proposed kingdom Protista & kingdom Monera
66
Robert Whittaker
Proposed adding kingdom fungi
67
*Haloquadratum walsbyi*
- Genus describes salt water habitat & arrangement of its square cons
- named after Anthony Edward Walsby
68
*Mycobacterium leprae*
Causes leprosy
69
*Dracunculus medinensis*
- Helminth; guinea worm
- causes dizziness, vomiting, diarrhea, ulcers in legs & feet where worm exits skin
70
*Staphylococcus aureus*
- Gram-positive bacterium that consists of clustered cocci cells
- ability to evade antimicrobials, particularly methicillin
71
E. coli O157:H7
- Causes abd. cramps & diarrhea
- originates from contaminated water or food
72
*Giardia lamblia*
- intestinal protozoan parasite that infects humans & other mammals
- causes severe diarrhea
73
*Candida albicans*
- unicellular fungus/yeast
- causes vaginal yeast infections, order finish
- morphology similar to coccus bacteria
- eukaryotic organism
74
*Saccharomyces cerevisiae*
- yeast
- makes beer, wine, bread
- fermentation yields ethanol & carbon dioxide
75
Aristotle
earliest recorded scholars to articulate theory of spontaneous generation
76
John Needham
- believed theory of spontaneous generation
- performed experiment with boiled both infused with plant or animal matter
77
Lazzaro Spallanzani
- Didn't agree with Needham’s conclusion
- performed hundreds of experimentswith heated broth with sealed & unsealed flasks
- concluded that "Life force" was killed during Needham’s experiment
78
Structure of prokaryotic chromosomes
a single circular chromosome located in a nucleoid
79
Structure of prokaryotic plasmids
small, circular, double stranded DNA molecules
80
Structures associated with prokaryotic cells
- lack membrane bound organelles
- has cell membrane, chromosomal DNA in nucleoid, ribosomes, cell wall
- some have flagella, pili, fimbriae, capsules, inclusions
- nucleoid associated proteins (NAPs) help package DNA
81
Structure & function of inclusions
- cytoplasmic structures
- store excess nutrients, glycogen, starches
- magnetosomes, metachromatic granules, gas vacuoles
82
Structure & function of endospores
- vegetative bacterial cell; dormant state when environmental conditions are unfavorable
- survive long periods w/out food or water
83
Structure & function of plasma membrane
- phospholipid bilayer embedded w/various proteins
- glycoproteins (carbohydrate w/protein)
- glycolipids (carbohydrate w/lipid)
84
Structure of peptidoglycan
- composed of long chains of alternating molecules of N-acetylglucosamine (NAG) & N-acetylmuramic acid (NAM)
85
Acid fast positive cell wall
- external layer of mycolic acids in cell wall
- stains that must stand up to acids used
86
Structure & function of capsules
- organized firm layer located outside of cell wall
- usually composed of polysaccharides or proteins
87
Structure & function of slime layers
- less tightly organized layer
- loosely attached to cell wall and more easily washed off
- may be composed of polysaccharides, glycoproteins, glycolipids
88
How do retroviruses integrate into host genome?
- has enzyme called reverse transcriptase
- reverse transcriptase makes complementary ssDNA (cDNA) copy using +ssRNA genome as template
- ssDNA made into dsDNA
- dsDNA integrates into host chromosome to form provirus
- provirus remains and can cause chronic infection
89
Virus helical capsid shape
- cylindrical or rod shaped
- genome fits just inside length of capsid
- can be enveloped or naked
90
Virus polyhedral capsid shape
- consist of nucleic acid surrounded by polyhedral capsid in form of icosahedron
- icosahedral capsid is 3D, 20 sided structure w/12 vertices
- can be enveloped or naked
91
Virus complex capsid shape
- example: bacteriophages
- genome located w/in polyhedral head
sheath connects to head to tail fibers & tail pins that help virus attach to receptors on host cell surface
92
Examples of latency & latent viruses
- latent viruses can remain latent or asymptomatic inside cell for extended periods
- herpes simplex virus (oral & genital herpes)
- varicella-zoster virus (chickenpox, shingles)
- Epstein-Barr virus (mononucleosis)
93
Virions
new virus particles formed from viral components, proteins, nucleic acids synthesized by host cell the virus is inhabiting
94
Virusoids
- subviral particles; non-self-replicating ssRNAs
- 220-388 nucleotides long
- require helper virus like HBV
-
95
Prions
- discovered by Stanley Prusiner
- proteinaceous infectious particles
- PrPc + normal; PrPsc = not normal = prion
- transmission occurs from animal to animal, animal to human, eating contaminated meat, heredity, contact with contaminated tissue
- cause transmissible spongiform encephalopathy (TSE)
- include kuru, mad cow disease, scrapie
96
Structure of virions
capsid encloses genome of either DNA or RNA
97
Structure of capsids
- surrounds viral genome
- composed of protein subunits called capsomeres that are made of different protein subunits that interlock to form capsid
98
Robert Koch
- proposed series of postulates based on idea that cause of specific disease could be attributed to specific organism
- Koch & colleague found causes of anthrax, TB, & cholera
99
Gram-positive cell wall
- Gram-positive cell wall is NAG, NAM, NAG, NAM, etc. cross linked by peptide bridges
- consists of many layers of peptidoglycan 30-100nm in thickness
- peptidoglycan layers embedded w/ teichoic acids (TAs) that extend thru layer
100
Gram-negative cell wall
- Gram-negative cell wall is NAG, NAM, NAG, NAM, etc. w/direct link
- thin layer of peptidoglycan ~4nm thick
- gel-like matrix occupies periplasmic space between cell wall & plasma membrane
- 2nd lipid bilayer external to peptidoglycan layer called outer membrane that contains lipopolysaccharide (LPS)
- LPS composed of Lipid A, a core polysaccharide, an O side chain
101
structure & function of glycocalyx
- sugar coat with 2 different types
- capsule & slime layer
- allow cells to adhere to surfaces, aide in formation of biofilms
102
monotrichous flagella arrangement
a bacterium w/a singular flagellum located at one end of the cell
103
amphitrichous flagella arrangement
flagellum or tufts of flagella at each end of cell
104
lophotrichous flagella arrangement
have tuft of flagella at one end of cell
105
peritrichous flagella arrangement
flagella cover entire surface of cell
106
H1N1 influenza
- outbreak in 2009
- spread across various continents
107
Ebola
early 2014 epidemic in western Africa
108
COVID-19
- began 2019; pandemic
- 4.5mil deaths worldwide
- 640K deaths USA
109
Edward Jenner
- inoculated pts with cowpox to prevent smallpox
- technique he called vaccination
110
host specific (host tropism)
viruses only infect certain type of host
111
tissue tropism
viruses only infect certain types of cells within tissues
112
steps of lytic cycle
- attachement
- penetration
- biosynthesis
- maturation
- lysis
113
steps of lysogenic cycle
- attachment
- penetration
- integrates into bacterial chromosome
- becomes integrates prophage
- lysogenic conversion (phage conversion) - change in host phenotype
114
viroids
- consist of only short strand of circular RNA capable of self replication
- result in devastating losses of food crops
