Question Answer
bacterial cell wall structure is the basis for distinguishing what? Gram-positive
bacteria that are thin, long and coiled spirochetes
spirochetes flagella they have unique flagella for motility
periplasmic flagella (or internal flagella, endoflagella, axial filaments)
axial filaments cause cell to causes the cell to move by rotating
transporters are_________ on cell membrane selective permeable
Why is pili produced? -usually produced when the density of microbes is high is response of sensing
cork screw motion of motility
swim in a vicous environment
-smaller than flagella, fine, proteinaceous, hairlike-bristles from cell surface
-important for attachment to surface and adhesion during pathogenesis
bind to throat, bladder, etc. to surface
establishes first step of attachement
What can resist phagocytosis and be presented from being engulfed by white blood cells? -encapsulated bacteria
cell membrane functions 1. energy generation
-procaryotic cell membrane is the site for electron transport chain during aerobic respiration
2. cell integrity
3. transport
What forms energy production on the cell membrane? electron transport chain
All bacteria have a _____________ double membrane
peptidogylcan peptide (protein) and glycan (sugar)
-a complex molecule composed of glycan chains crossed linked by peptide chains
What does a peptidoglycan layer look like and why? chain linked fence because it has wholes and does not block molecule provides mechanical support cell
-strengthen each other with chain and another chain link
In gram stain, cells either stain _________ (____) or ________ (_____) purple-gram positive
pink-gram negative
gram positive bacteria a thick cell wall composed primarily of peptidoglycan
gram negative bacteria have a thin peptidoglycan layer, but have an outer cell membrane
What are two important components of the cell wall? lysozyme and penicillin
-an antibacterial protein secreted by many organisims
-it hydrolyzes the glycan chain
-like bacteria cells
-cuts glycan chain
-inhibits the formation of peptide crosslink in dividing cells
-causes cell to targets and different part of glycan either way when treated with 2 agents will be killed
procaryotes external structure flagella, pili, fimbriae
return to vegetative growth from spore form; triggered by nutrients germination
-a process that results in the formation of endospores
-can be caused by nutrient depletion
cell envelope -glycocalyx (capsule, slime), cell wall, cell membrane
procaryotes internal structure chromosome (nucleiod) ribosome, inclusion bodies
What does a cell do? 1. Growth and Development
2. Reproductive and heredity
3. Metabolism
4. Movement and/or irritability
5. Cell support
6. transport of nutrients
Reproduction and heredity genetic materials, reproduce offspring sexually or asexually
metabolism -chemical and physical life processes
movement and or irritability -respond to internal/external stimuli
cell support, protection and storage mechanisms -cell walls
-transport of nutrients and waste
Flagellum/Flagella 1.filament
3.basal body
-rotates 360° in response to signals
-1-2 or many distributed over entire cell
-functions in motility
curved sheath hook of flagella
stack of rings firmly anchored in cell wall and membrane basal body of flagella
long thin helical structure composed of proteins filament of flagella
small bunches ariving from one end of cell lophotrichous
single flagellum at one end monotrichous
flagella at both ends of cell amphitrichous
flagella dispersed over surface of cell peritrichous
Which is most motile flagella arrangement? peritrichous
________function to guide bacteria in a direction in response to external stimuli flagella
bacteria movement in response to chemical signals chemotaxis
movement toward or away from light phototaxis
flagella location and reason -between 2 membranes so when it turns can cause bacteria cell to move distinctly from flagella outside of cell
spirochetes flagella location -between the inner and outer membrane
[spirochetes flagella] function in motility -twisting and corkscrew
syphilis -spiral bacteria
-sexually transmites
-initiates intake of bacteria
pili -rigid tubular structure made of pili protein subunits
1.joins two bacterial cells, enable DNA transfer, from one cell to another ("conjuction")
2. adhesion
glycocalyx -coating of molecules external to the cell wall, made of sugars (main compartment) and or proteins
capsule one type of glycocalyx
highly organized, tightly attached
slime layer -loosely organized and attached
-one type of glycocalyx
-allows bacteria to attach
-bad causes tissue/heart damage
capsule function -encapsulated cells exhibit smooth morpholgy (smooth vs. rough)
Function: protects bacteria from being destroyed by host phagocytes (white blood cells)
-capsule is associated with pathogenic bacteria
slime layer function enable attachment and aggregation of bacterial cells on solid surface
-involved in biofilm formation
Cell Membrane -bacterial cytoplasmic membrane composed of phospholipids bilayer embedded proteins
eukaryotic energy is produced where? -on mitochondria
cell wall 1. located directly outside the cell membrane because membrane can burst
2. bacterial cell wall contains the macromolecule peptidoglycan
3. function: mechanical support of the cells
cell wall function mechanical support of cells: maintain shape, keep bacteria from bursting due to changes in osmotic pressure
peptide crosslink is between two M sugars G: NAG
not found in protein but in cell wall D-glutamate
What is the result of lysozyme or penicillin treatment? cell burst
lysozyme cuts between sugars
penicillins prevent crosslinks from forming
endospore formation and types -formed with in the cell
-produced by some G+ genera:
Clostridium, Bacillus and Sporosacrcina
What type of cells are endospores?
How are they developed?
-they are resting, dormant cells
-developed from vegetative cells when conditions become nonfavorable
Why is it said that endospores are the "hardiest of all life forms"? 1. withstand extremes in heat, drying, freezing, radiation and chemicals
2. longevity verges on immortality (25-250 million years)
3. resistant to ordinary cleaning methods and boiling
4. Sterilization methods usually kill spores
What specifically will kill endospores? -pressurized steam at 120°C for 20 to 30 minutes will destroy this
endospores contain high levels of ______ and ____________ -calcium
-dipicolinic acid
(mutent of cell no longer produce this chemical)
important for heat resistance
the core of endospores are ___________ dehydrated
important for heat resistanceEn
Endospores have a thick ____________ thick protein coat
important for chemical resistance
Endospores are ___________ inactive
>important for _____________
-radiation resistance
Spore-forming bacteria have a _______ life cycle: 1._______ and 2.________ 2 phase life cycle
1. vegeatative cell
2. endospore form
vegetative form -actively growing
-metabolizing, or
-producing toxins in some pathogenic species (such as B. anthracis, C. tetanus)
-found in food tissues
What is vegatative form sensitive to? chemicals, heat, drying and antibiotics
spore-form resistant form often found in soil or air
endospore causes disease the vegetative part causes what? -tissue damage
-contains crystals of magnets
-highly organized species granules
-makes them into magnetic field to find optimum oxygen environment
it grows when stressed out about oxygen
-whether granuole formation it is more resisten to other factors
-found in GI tract
usually energy reserve and enviromental resistant as well (I think?)
-volutions, poly P
in Corymobacterium
metachromatic granules
-function in cell wall maintenance and enlargement during cell division; move cations across the cell envelope; stimulate a specific immune(or host) response teichoic acid lipoteichoic acid
composed of an outer membrane and a thin-layer of peptidoglycan
-has a periplasmic space
Gram negative cell wall
-enable a cell to store nutrients, and to survive nutrient depleted and other stress conditions What are granules other name and what is their function
-inculusion bodies
Gram positive cell wall -thick peptidoglycan (PG) layer
-acidic polysaccharides teichoic acid and lipoteichoic acid
lipid moleules inner/outer leaflet inner leaflet: phospholipid; outer leaflet: lipopolysaccharide (LPJ)
let certain molecules (<600 dalton) enter and leave cell, to compensate for the OM barrier effect Has porins
makes G-bacteria more impermeable to disinfectants dyes and certain drugs than G+ OM(outer membrane) makes what?
-can be released during cell lysis
-is often proinflammatory and cause damages to the infected host
-therefore LPS is also called enodtoxin (as opposed to exotoxin)
lipopolysaccharide (LPS)
lipopolysaccharide (LPS) explain part hidden in lipid but when will it be exposed driving blood infections which can cause endotoxic shock
Gram stain steps 1.make smear and apply crystal violet (primary dye)
2. add Gram's iodine (mordant)-functions as intensified binding
3. alcohol-can't be removed because of tight bond from mordant
4. add safranin (red dye counterstain) pink
Quick summary of gram stain steps 1. primary stain (crystal violet)
2. mordant (iodine)
3. decolarization (alcohol)
4. counterstain (safranin)
G+:purple G-:pink
function of ribosomes -site of protein synthesis
List 3 types of bacteria with unique cell wall structure and properties 1. Acid-fast bacteria
2. L-forms
3. Mycoplasmas
myobacterium apperance -waxy because in cell wall also have a waxy layer
mycolic acid (1) -unique lipids (<-? look up)
-the cells stain gram positive, but sometimes give beaded appearance
-in acid-fast stain, the waxy cell wall enables the cell to retain the carbolfuchsin dye even after stained by acid alcohol
mycolic acid (2) -cell wall lipids contribute to high degree of resistance to many dyes, disinfectants, and drugs
chromosome -usually a single DNA molecule tightly coiled and aggregated in a dense area called nucleoid
-DNAs in bacteria and archaea are usually circular dobule stranded DNA
-chromosomal DNA contains all essential genetic information for the cell
bacteria that have lost the cell walls due to drug treatment (and surviving!) L-forms
_____can cause some bacteria to develop alternative mechanisms for support. Those ____ are called_______. -mutations
-bacteria naturally lack a peptidoglycan cell wall
-live closely with host cells
-during evolution they have lost a lot of capabilities, including PG synthesis
-cell membrane contain sterols, for stability
-don't have cell wall have very irregular shapes
-take cholesteroal from our cells and strengthen them
-to survive in cell called mycoplasma
mycoplasm (again notes)
Know difference between mycobacterium and mycoplasma mycoplasm-no cell wall cell bacteria from with out all cell wall
transport sexually transmitted disease
gelatinous solution containing water, nutrients, proteins and genetic material
-(soup-inside of cells)
-insdie cell ribosomes unique gradually genetic material
DNA (full name and what it includes) What are the genetic material? -deoxyribonucleic acid (DNA)
-chromosome and plasmidss: the genetic materials
surrounds the thylakoids stroma
how many ribosomes are in eucaryotic organisms 80S ribosomes
eucaryotics are composed of what ribosome protein and rRNA
eucaryotics are assembled from the ______ and ______ subunits 40S and 60S
how different is eucaryotes from procaryotes different from 70S ribosomes of procaryotes
eucaryotes present where? cytoplasm and RER
granules can be organic or inorganic
hydroxyl buturate -for colony hydroxyl something
-when access nutrient available can be used when nutrient is needed
glycogen -polymers of glucose organisms usually makes them into polymers
inclusion bodies -granules
-often contain polymers, examples:
2.polyhydroxlbutyrate (PHB)
3.gas vesicles
4.polyphosphate granules (also called poly P, metachromatic granules or volutin granules)
Ribosome apperance 2 subunits
-large subunit (50S)
-small subunit (30S)
together make (70S) and form tight molded shape that is strong
ribosomes -super structures containg 3-4 long molecules
-ribosomal RNA (rRNA): 60%
-ribosomal proteins: 40%
plasmids application used in genetic engineering rendily manipulated and transferred from cell to cell
plasmids replication duplicated and passed on to offspring during cell division, independent of chromosome replication
genetic structures DNA, RNA
mycobacterium genus have several pathogens including ones causing TB and leprosy
acid-fast bacteria
Gram stain beaded skin dyes can't penetrate very well
Acid fast stain name two 1. M. tuberculosis
2. M. leprae


acid-fast stain is a diagnostic tool for what? 1. tuberculosis (mycobacterium tuberculosis)
2. leprosy (M. leprae)
What does Gram stain tell us? -shape of cell
-whether gram is positive or negative
-Important basis of bacterial classification and identification
-practical aid in diagnosing infection and guiding drag treatment
Gram stain importance and practicalness
Gram-negative -lose crystal violet and stain red form safranin counterstain
Gram-positive -retain the crystal violet dye and stain purple
The thickness of what is important from a gram stain PG (peptidoglycan)
1. Gram-positive
2. Gram-negative
Gram stain -differential stain that distinguishes cell with a Gram-positive cell wall from those with a Gram-negative cell wall
outer membrane (OM) in gram negative bacteria more info to come
lipopolysacchrid 3 components:
-list here:
try to understand the process of lactose -not fermented by all organisms the lack of enzyme is reponsible inability to ferment lactose organisms in a way
size of Ribosomes 70S consists of 2 subunits large (50S) and small (30S)
-procaryotic ribosomes are different from eucaryotic ribosomes in size and number of proteins (70S vs. 80S)
What cells have ribosomes? all
plasmids genetic information encoded by plasmids -not essential to bacterial growth and metabolism
-may encode antibiotic resistance tolerance to toxic metals enzymes and toxins that allow the cells to survive better
important for the spread of drug resistance
-smaller, circular double-stranded DNA
-free or integrated info the chromosome
-copyy number can vary from 1-500
What do procaryotic cells have instead of a nucleus chromosomes
RNA Ribonucleic acid
Ribosome RNA (rRNA)
Messenger RNA (mRNA)
Transfer RNA (tRNA)
Ribosomes: protein synthesis

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