exam 1 micro – Flashcards

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question
importance of leeuwenhoeks discoveries
time
benefits?
answer
mid to late 1600s
- understanding the relationship between the microscopic world and the world we can see with out eyes,,, he made it so we can actually see and study this invisible world


- the benefits are knowing that most of life is microbial and having knowledge of the affects these microbes have on us.
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when was the golden age of microbiology
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late 1800s early 1900s
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yeasts
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unicellular
typically oval or round
reproduce asexually by budding(daughter cell grows off mother cell)
some yeast also have sexual spores
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protozoa
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single celled eukaryotes that are similar to animals in nutritional needs and cellular structure "greek for first animals"
-capable of locomotion
-classified according to their locomotive structures: pseudopods(flow in direction of travel), cilia(short protrusions for repelling), or flagella(longer, less numerous than cilia)

-some may cause disease
-most asexual, some sexual
question
glyocalyces
2 types
functions
answer
composed of polysaccharides, polypeptides, or both.

capsule or slime layer

-provides protection rom drying out and can play a role in the ability of pathogens to survive and cause disease
- allows FOR ATTACHMENT TO SURFACES
-ex; unencapsulated strains of bacteria that cause pneumonia don't cause it because defensive cells can destroy it
question
spherical=
rod like=
what do they exist in (form?)
answer
spherical= COCCI(single,chains, clusters, or cuboidal packets)
rod like= BACILLI (single or chain)
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mycoplasma
answer
a bacteria that doesn't have a cell wall
question
cell walls are composed of ___________
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peptidoglycan - a complex polysaccharide made of repeating subunits of N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM) which are like glucose

- chains are attached to other chains by cross links of four amino acids (tetra peptides)
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what do you call 4 amino acids joined by peptide bonds, and where would you find one
answer
a tetrapeptide
the cell wall
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gram positive
answer
thick layer of peptidoglycan that also contains unique chemicals called teichoic acids (gives surface negative charge) some of which are covalently linked to lipids forming lipoteichoic acids (anchor the peptidoglycan)
-APPEARS PURPLE
-no porins


1. cross linking heavy
2. thick layer of peptidoglycan
3. teeichoic acid (give surface -)
4. lipoteichoic acid (anchor the peptidoglycan)
question
gram negative
answer
thin layer of peptidoglycan, but outside this layer there is also another outer bilayer membrane(external to the cell wall) composed of two different layers.
inner layer: phospholipids and proteins
outer layer: lippopolysaccharide/LPS (endotoxin). when these cells die they release a lipid which causes symptoms.

1.cross linking lightly
2. thin layer of peptidoglycan
3. lipoproteins, phospholipids, in extra outer bilayer membrane (inner layer of it)
4.LPS layer- created by union of a lipid and sugar (contains lipid A also known as endotoxin (in the lipid portion) which causes symptoms such as fever, vasodilation, inflammation, shock, and blood clotting in humans )
5. drugs are a danger due to this lipid A being a threat when the cells die
6. drugs may be ineffective due to outer layer stopping the entrance of drugs like penicillin into the underlying peptidoglycan
6. contains a periplasmic space which contains the petidoglycan and periplasm
question
what extra chemical does gram positive bacteria have?
answer
teichoic acids
question
techie acids covalently link to lipids and form
answer
lipoteichoic acids
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what do lipoteichoic acids do
answer
anchor peptidoglycan
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mycobacterium
answer
-species that have 60% my colic acid in their ell walls
-mycolic acid: a waxy lipid, helps cells survive drying out
- the my colic acid makes staining difficult
- ACID FAST STAIN USED
-CALLED ACID FAST BACTERIA
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ribosomes
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-protein synthesis
-translation
-in prokaryote all ribosomes exist in cytoplasm
-ribosome smaller in prokaryote
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internal structures of prokaryote
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cytoplasm (required)
ribosomes (required)
genetic material (requires)
endospores (optional)
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endospores
answer
- bacillus or clostridium (both human pathogens)
-bacterial cells that are metabolically active are called vegetative cells, these cells produce endospores which are metabolicaly dormant
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based on how the endospore is made, the end result is very resistant to ?
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dehydration, heating, freexing, UV light
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sporulation
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the process of making an endospore ( which protects chromosome so it isn't destroyed)
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4 things all cells have:
answer
cell membrane, cytoplasm, genetic material, ribosomes
question
cocci-
bacilli-
vibrio-
spirilli-
spirochete-
answer
cocci- diplococci, streptococci,staphylococci

bacilli- diplobacilli, streptobacilil

vibrio- rod shaped with slight curve, comma shape

spirilli- rod shaped, twisted, very stiff, exist only as individual

spirochete- rod shaped, twisted, but very flexiblelike slinky, only exists as individual
question
how does penicillin work
answer
it inhibits cross link formation in newly synthesized cells
- this damages boundary structures of the cells cane the cells die because our bodies are hypotonic
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which have phosphoolipids in the cell membrane? gram positive or gram negative?
answer
both
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sketch gram positive and negative cell walls
answer
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mycobacterium is gram _______ and ________ acid is also found in the cell wall
answer
gram positive
mycolic acid
question
for bacteria the cell wall provides protection from osmosis but only if it is in a __________ environment
answer
hypotonic
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what are the two families of endospore we are interested in
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bacillus and clostridium (human pathogens) naturally found in soil, typically in the endospore state where would easily encounter them.
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anthrax
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bacillus anthracis endospores put in envelopes and mailed and then inhaled
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archae lack
answer
peptidoglycan in the cell wall
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peptidoglycan is a complex ___________made of repeating subunits of ________ and ________

chains are attached to other chains by _______ which are cross links of four amino acids
answer
is a complex polysaccharide
repeating subunits of NAG, NAM
tetrapeptides
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catabolism, anabolism
answer
catabolism-process of breaking down macromolecules into smaller molecules (ATP generated, energy stored)

anabolism- taking individual small molecules and combining them to make macromolecules
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metabolic reactions involve transfer of _______ and are called _________ reactions
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electrons, redox
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substrate level vs oxidative
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substrate level- takes place during glycolysis (cytoplasm)
oxidative phosphorylization- takes place during cellular respiration (chemiosmosis formatiion of atp)
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cellular respiration steps
answer
cellular respiration= a process that results in the complete breakdown/oxidation of glucose to CO2 and H2O 1. glucose
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catabolic reactions are _______ meaning they release energy

anabolic reactions are _____ meaning they require energy
answer
exergonic catabolism
endergonic anabolism
question
electron carrier molecules
answer
used to carry electrons from one location in a cell to another
important electron carrier molecules(derived from vitamins):
-nicotinamide adenine dinucleotide (NAD+),
-nicotinamide adenine dinucleotide phosophate (NADP+)
- flavin adenine dinucleotide (FAD)

(USED TO CARRY PAIRS OF ELECTRONS)
(one electrons carried by either NAD+ or NADP+ is part of a hydrogen atom, forming NADH or NADPH. FAD carries two electrons ad hydrogen atoms (FADH2))
question
during__________organisms release energy from nutrients that can be concentrated and stored in high energy phosphate bonds of molecules such as ATP. this happens by a process called ____________ in which inorganic phosphate is added to a substrate.
answer
catabolism
phosphorylization
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cells phosphorylate ADP to form ATP in 3 ways
answer
1. substrate level phosphorylation- transfer of phosphate to ADP from another phosphorylated organic compound
2.oxidation phosphorylation- energy from redox reactions of respiration is used to attach inorganic phosphate to ADP.

3.photophosphorylation- light energy is used to phosphorylate ADP with inorganic phosphate.
question
cellular respiration results in
answer
the complete breakdown of glucose to carbon dioxide and water
question
glycolysis
answer
*takes place in cytoplasm/cytosol
*2 NADH (reduced), 2 ATP formed
*first step of respiration and fermentation
*break down of glucose molecule to two 3 carbon sugar molecules which are oxidized to pyretic acid and some energy released is stored in ATP and NADH
the direct transfer of the phosphate between
the two substrates is the reason the process is called substratelevel phosphorylation.

2 ATP molecules used
4 ATP produced
2 ATP net gain
2 NADH yielded
a net gain of two ATP molecules occurs for each molecule of glucose that is oxidized to pyruvic acid. Glycolysis also
yields two molecules of NADH.
question
2 NADH and 2 ATP are formed during
answer
glycolysis
question
cellular respiration
answer
1. begins with glycolysis (cytoplasm)
2. synthesis of acetyl CoA: pyruvic acid is converted. 2 pyruvic acid> 2 acertyl-Co-A
3. Krebs cycle (mitochondria): 2 FADH2 molecules, 6NADH, 2ATP
4. electron transport chain( final series of redox reactions that passes electrons to alchemical not derived from the cell's metabolism): (in eukaryotes in mitochondria, prokaryotes:cell membrane)
question
cellular respiration involved the complete ______ of substrate molecules and then production of _______ by a series of ______ reactions
answer
OXIDATION of substrate molecules and then production of ATP by a series of REDOX reactions
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the process of making ATP through the electron transport chain
answer
oxidative phosphorylation
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the krebs cycle takes place in the _________
answer
mitochondria
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what is also formed when pyruvic acid is converted to acetyl Co A
answer
one molecule of NADH
question
the krebs cycle
what is produced
answer
a great amount of energy is in the bonds of acetyl CoA
- the krebs cycle is a circular series of eight enzymatically catalyzed reactions that transfer much of this stored energy to the coenzymes NAD+ and FAD. (the two carbon atoms in acetate are oxidized, and the coenzymes are reduced)
OCCURS IN MITOCHONDRIA

*PRODUCES 2 FADH2 molecules, 6 NADH, 2 ATP
question
in the krebs cycle the coenzymes are ________
answer
reduced
NAD>>>6 NADH
DAF> 2 FADH2
question
after the krebs cycle which leaves energy in electron carrier molecules how do we get the ATP from these molecules?
answer
via the electron transport chain:
question
the electron transport chain occurs where
answer
in prokaryotes- the cell membrane
in eukaryotes- the mitochondria matrix

1. NADH has hydrogen removed leaving NAD+,
2. the electron is pickd up by electron transport chain and passed down the chain and
3. as it is passed down the chain the hydrogens are pumped across creating a proton gradient (H+ gradient) which generates ATP through chemiosmosis
4. the final electron acceptor is oxygen
5. atp synthase- protons flow throguh atp synthase which phosphorylates ADP to ATP.
*ONE ATP FOR 2 PROTONS CROSSING THRU
question
for every 2 molecules of AcetylCOa that pass through the krebs cycle, ________ are generated via __________ phosphorylation
answer
2 ATP, substrate phosphorylation
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for each 2 protons crossing through ATP synthase (electron transport) how many ATP
answer
1
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fermentation
answer
1. glycolysis
2. pyruvic acid> alcohol or acid because NAD needs to be recycled/regenerated in order for glycolysis to continue
3. only generates 2 ATP
4. yeast produces alcohol
question
fermentation allows for regeneration of ______ for glycolysis so that ADP can be phosphorylated (allows ATP production to continue in absence of respiration)
answer
NAD+ for GLYCOLYSIS
question
chemiosmosis
answer
the general term for the use of ion gradients to generate ATP
question
________ produces the required NAD+ in respiration, but without a final electron acceptor, this source of NAD+ ceases to be available and must be provided by alternate __________ pathways
answer
ELECTRON TRANSPORT produces required NAD+ in respiration

FERMENTATION
question
fermentation is the partial __________ of sugar to release energy using an organic molecule from within _______ as the final electron acceptor.
answer
oxidation
the cell
question
fermentation pathways are metabolic retains that oxidize _______ to _____ while reducing cellular organic molecules.
answer
NADH to NAD+
question
the essential function of fermentation is the regeneration of _______ for _______ so that ADP molecules can be phosphorylated
answer
NAD + for GLYCOLYSIS
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fermentation pathways are _______ efficient than respiration
answer
less, because much of the potential energy stored in glucose remains in the bonds of fermentation products
question
why are catabolic reactions important?
answer
they release energy used to drive chemical reactions
question
during krebs cycle what is produced (respiration)
answer
-6 NADH, 2 FADH2, 2 ATP
question
what is the point of the krebs cycle
answer

to transfer energy from acetyl coA bonds to NAD+ and FAD

 

NAD+ and FAD reduced to NADH+ and FADH

 

6NADH+ and 2 FADH2 and 2 ATP

question
___________ phosphorylization takes place during krebs cycle and glycolosis while _________ phosphorylization takes place at the end of cellular respiration.
answer

SUBSTRATE LEVEL- krebs and glycolysis

OXIDATIVE- cellular respiration

question
photoautotroph
answer
-energy from chemicals, carbon from co2

-plants, algae, cyanobacteria
-green and purple sulfur bacteria use H2S as electron source so they DONT PRODUCE oxygen
question
chemoautotroph
answer
-energy from chemicals, carbon from co2
-hydrogen, sulfur, and nitrifying bacteria
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photoheterotroph
answer
-green and purple non sulfur bacteria ( use organic compounds for carbon source) (light for energy)
-archaea
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chemoheterotrophs
answer
-animals, us, molds, protozoa, bacteria, yeasts, fungi (chemical energy source, organic carbon source)
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facultative anaerobe
answer
-prefers to use oxygen
-does not need to
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aerotolerant anaerobe
answer
doesn't use oxygen
tolerates its present
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toxic forms of oxygen
answer
1.singlet oxygen O2, polyphenol needed
2. superoxide radical O2, must make superoxide dismutase
3. peroxide anion O22-, must make catalase or peroxidase
4.hydroxyl radical OH- must make antioxidants (melatonin, vitamin E)
question
steps of biofilm
answer
1. free microbes are vulnerable to environmental stress and land on surface
2. cells begin making extracellular matrix and secrete quorum sensing molecules (DNA, protein, polysaccharides)
3. quorem sensing triggers cells to change biochemistry and shape
4. new cells arrive, possible including new species, and water channels form in biofilm
5. some microbes may escape
question
quorum sensing triggers
answer
previously suppressed genes to change shape, production of enzymes, etc
question
logarithmic/exponential growth phases
answer
1.lag phase- adjustment for cells to make enzymes and start reproducing again, fairly short
2. log stage/exponential- cells dramatically increase

INCLOSED ENVIRONMENTS ONLY
3. stationary phase- cells begin to die due to lack of nutrients
4. dead stage/decline stage- cells dying faster than reproducing
question
which phase is most sensitive to antimicrobial drugs
answer
log phase
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