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76 Cards in this Set
- Front
- Back
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Name of process of bacterial reproduction
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binary fission
It is asexual |
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Process of binary fission
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1. Enlargement in cell size
2. DNA replication 3. Cell wall and membrane grow inward 4. Transverse septal wall formed 5. 2 daughter cells complete |
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4 phases of bacterial growth curve
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1. Lag phase
2. log (exponential) phase 3. stationary phase 4. death phase |
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At what phase in bacterial growth curve do bacteria begin to die?
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stationary phase (no cell death in log phase)
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TEST QUESTION
At what phase in bacterial growth curve are antibiotic most effective? |
log stage (most antibiotic target cell biosynthesis--protein, DNA, and cell wall synthesis
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Three temperature-dependent classes of bacteria
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Mesophiles (20-45 degrees)
Thermophiles (45-110 degrees) Psychrophiles (0-20 degrees)...psycho because they like the cold! |
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Three groups of bacteria which like different pH environments
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Neutrophils: 5-8
Acidophils: 0-5 Alkalinophiles: 8-12 |
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TEST QUESTION
Most human pathogenic bacteria belong to which temperature liking group and which pH-liking group |
Mesophiles and Neutrophiles (conditions found in human body)
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Which type of bacteria grow in aerobic conditions, don't group in anaerobic conditions, and require O2 for aerobic respiration?
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Obligate Aerobe...Obligated to live on Oxygen
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Which type of bacteria grow in slightly aerobic conditions, don't group in anaerobic conditions, and require a low level of O2 to survive?
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Microaerophile--
"micro" little "aerophile" oxygen lover |
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Which type of bacteria grow in anaerobic conditions, don't group in aerobic conditions, and O2 is toxic to them?
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Obligate anaerobes
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Which type of bacteria grow in aerobic and anaerobic conditions, and O2 is not required for growth but utilized when available
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Facultative
(strep. mutans in mouth which causes decay) |
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Which type of bacteria grow in aerobic and anaerobic conditions, and O2 is not required nor utilized when available?
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Aerotolerant anaerobe
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Which of the following will die with normal (21%) amount of O2 in air?
A. Facutative B. Aerotolerant anaerobe C. Obligate Aerobe D. Microaerophile |
D. Microaerophile (needs 2-10% O2 levels)
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What are two types of reactive oxygen species toxic to bacteria?
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superoxide
peroxide |
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What 3 enzymes detoxify reactive oxygen species in bacteria?
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superoxide dismutase
peroxidase catalase |
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Obligate aerobes and most facultative anaerobes have which of the following (may be multiple or none)
A. superoxide dismutase B. peroxidase C. catalase |
superoxide dismutase and catalase
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Most aerotolerant anaerobes have which of the following (may be multiple or none)
A. superoxide dismutase B. peroxidase C. catalase |
superoxide dismutase and peroxidase
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Obligate anaerobes have which of the following (may be multiple or none)
A. superoxide dismutase B. peroxidase C. catalase |
none
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T/F: ALL metabolically active bacteria require water.
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True
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What kind of bacteria require light?
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cyanobacteria
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UV light is lethal to what kind of bacteria?
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nonphotosynthetic bacteria (eubacteria)...because it causes mutations
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What kind of nutrients do bacteria not require for growth?
A. C B. N C. H D. P E. O |
D. Phosphorus is not on the list
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TEST QUESTION
human pathogenic bacteria are: A. photoautotrophs B. chemoheterotrophs C. photoheterotrophs D. chemoautotrophs |
B. Chemoheterotrophs
organic compounds carbon source Use ready-made organic molecules for food (don't make it themselves) |
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T/F Catabolism breaks down substrate to release energy and anabolism is when energy is used to synthesize new molecules.
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True
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What are four energy-storage molecules
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ATP
GTP NADH FADH2 |
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glycolysis is catabolism or anabolism?
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catabolism
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kreb's cycle is catabolism or anabolism?
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catabolism
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fermentation is catabolism or anabolism?
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catabolism
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biosynthesis mechanisms are catabolism or anabolism?
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anabolism
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Does anabolism or catabolism use energy-storage molecules
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anabolism
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What are 2 primary energy-storage molecules
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ATP and GTP
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Molecule that is the primary energy currency of bacteria
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ATP
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What are 2 secondary energy-storage molecules
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NADH and FADH2
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Where must secondary energy-storage molecules such as NADH and FADH2 go in order to transfer their energy into ATP?
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Electron Transport Chain
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How many ATPs come from NADH?
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3
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How many ATPs come from FADH2?
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2
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What are three catabolistic pathways in aerobic conditions
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1. glycolysis
2. krebs cycle 3. electron transport chain |
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What are two catabolistic pathways in anaerobic conditions
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1. glycolysis
2. fermentation |
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Does glycolysis occur in aerobic conditions? in anaerobic conditions?
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yes and yes. both.
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What are the gross products of glycolysis? net products?
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Gross: 4 ATP, 2 pyruvate
Net: 2 ATP, 2 pyruvate (2 ATP are needed and are expended in glycolysis process) |
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What is the key molecule that enters the TCA (Kreb's cycle)
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pyruvate
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What cellular metabolic process produces the most various energy-storage molecules (such at GTP, NADH, and FADH2)?
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kreb's cycle
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EXAM QUESTION
How many net ATP are generated, in aerobic conditions, from one glucose molecule? |
38!
38! 38! |
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In anaerobic conditions, pyruvic acid is turned into a variety of organic acids and alcohols
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FYI
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Besides glycolysis, Kreb's cycle, ETC, and fermentation, what are 2 other catabolic pathways for glucose?
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Pentose-phosphate pathway
and Entner-Duodoroff pathway (in prokaryotes--mostly obligate aerobes) |
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Why is bacterial gene exchange medically significant?
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antibiotic resistance
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Name the term where a plasmid (either free or integrated into the bacterial chromosome) moves from one bacterium to another
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conjugation
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Name the term where one bacterium releases phages which infect other bacteria
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transduction
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Name the term where DNA fragments from a lysed bacterium are taken up into and integrated into the genome of another bacterium.
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transformation
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Rank from most common to least common: Transformation, Conjugation, and Transduction
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Conjugation>transduction>transformation
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Compare and contrast plasmids and transposons
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Plasmid: extrachromosomal DNA that can autonomously replicate
Transposon: mobile DNA elements that jump from one place to another on the same chromosome Commonly, plasmids and transposons both can carry antibiotic resistance genes |
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Griffith experiment in 1928 is an example of what kind of genetic transfer
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transformation
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Transformation requires what?
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DNA fragment from a donor cell
Calcium |
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What are competent cells?
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Cells able to take up exogenous DNA
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Can Gram + undergo transformation?
Can Gram - undergo transformation? |
yes. yes
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TEST QUESTION
In what growth phase do bacteria develop competence? |
late log (start to die, become more desperate)
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Conjugation requires which bacterial structure?
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pilus
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T/F: Conjugation occurs only from fertility factor positive cell (F+) to fertility factor negative cell (F-)
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true
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T/F: genes necessary for conjugation, including pilus biogenesis genes, are found in the bacterial chromosome
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False. found in the F plasmid
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When F plasmid is integrated into the bacterial chromosome, an F+ bacterial cell becomes what?
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Hfr (high frequency recombination) cell
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What is transferred through the pilus from an Hfr cell to a F- cell
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Entire chromosome (including bacterial chromosome with F plasmid insert)
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Transduction occurs via what means?
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bacteriophages
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FACT: In generalized transduction, any host gene can be transferred
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FACT: In specialized transduction, only specific host genes are transferred.
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Which is the virulent (infecting) phase of bacteriophages: lysogenic or lytic?
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lytic
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Generalized transduction results from lytic and/or lysogenic cycle(s)?
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lytic only
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Specialized transduction results from lytic and/or lysogenic cycle(s)?
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both cycles
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Match:
Transformation requires [] pilus Conjugation requires [] phage transduction requires [] dead cell DNA |
ANSWER:
Transformation requires [] dead cell DNA Conjugation requires [] pilus transduction requires [] phage |
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"Jumping genes" mediate what process?
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transposition (of transposon)
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T/F: Transposition is when a DNA segment "jumps" from one bacterial chromosome to another.
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False. Transposition occurs within a cell, not between 2 cells
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in a transposon, the insertion sequence contains what?
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Transposase gene and/or antibiotic resistance genes
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Antibiotics trigger what four bacterial structures/processes?
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1. cell wall
2. DNA replication/ condensation (DNA gyrase and Topoisomerase IV) 3. transcription (RNA polymerase) 4. translation (50S and 30S ribosomal subunits) |
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Steps to cell wall (peptidoglycan) synthesis ONLY in bacteria.
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1. In cytoplasm, tetrapeptide forms and is added to NAM
2. NAM/tetrapeptide attaches bactoprenol and NAG attaches to NAM 3. transported to periplasmic space by bactoprenol 4. autolysins break glycosidic bonds along existing peptidoglycan 5. Transflycosylase enzymes form bonds between new and old NAG/NAM complexes 6. Transpeptidase reform pentaglycine cross-links |
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In Eukaryotes, DNA condenses with what?
In Bacteria, DNA condenses with what? |
Eukaryotes: histones
Bacteria: DNA gyrase (condense DNA) and topoisomerase IV (relax DNA) |
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How many subunits in bacterial RNA polymerase? In eukaryotic RNA polymerase II?
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4
12 |
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Ribosomal subunits in bacterial cell? In eukaryotic cell?
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Bacterial: 50s and 30s
Eukaryotic: 60s and 40s |
