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chapter 3
microbiology
84
Microbiology
Undergraduate 2
09/18/2015

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Term
prokaryote vs eukaryote
Definition
prokaryote- no membrane bound organelles like nucleus
eukaryote- plants, animals, contains membrane bound organelles
Term
glyocalyces
2 types
functions
Definition
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
Term
capsule
Definition
when the glycocalyx of bacterium is composed of organized repeating units of organic chemicals firmly attached to the cell's surface.
Term
slime layer
Definition
when the glycocalyx is loose and water soluble
Term
flagella
Definition
-most notable means of movement
-long hollow filament, a hook, and a basal body.
- composed of flagellin protein
- lengthens by growing at its tip
-ract to external wetness and inhibit growth in dry habitats.
-TAXIS=MOVEMENT IN RESPONSE TO STIMULUS (light or chemicals) receptors for light or chemicals on the surface of the cell send signals to the flagella, which then adjust their speed and direction of rotation.

A. petitrichous flagella- cover the surface of the cell
B. single polar flagella- only at end
C.tuft of polar flagella- a few at ends only
Term
taxis
Definition
movement in response to stimulus (flagella)
Term
what kind of flagella cover the surface of the cell
Definition
peritrichous flagella
Term
what is the most notable means of movement
Definition
flagella
Term
fimbriae
Definition
rod like extensions made of protein, sticky, bristle like and they adhere to one another and to substances in the environment (MORE NUMEROUS AND SHORTER THAN FLAGELLA)

-ATTACHMENT TO OTHER BACTERIA AND SURFACES
- IMPORTANT IN BIOFILMS (attach using fimbriae and lycocalyces)
- SOME ACT AS ELECTRICAL WIRES
-PILUS- fimbriae used to transfer dan from one cell to another
Term
what external structure allows for attachment to other bacteria AND surfaces
Definition
fimbriae
Term
what are the rod like extensions made of protein, sticky, bristle like
Definition
fimbriae
Term
pilus
Definition
a special type of fimbriae that is used to transfer DNA from one bacterial cell to another by a process called CONJUGATION
Term
function of cell wall
Definition
-provide structure and shape to cell
- protects from osmotic forces
- assists some cells in attaching to other cells or in resisting antimicrobial drugs.
- gives bacteria cells their shaoes
Term
spherical=
rod like=
what do they exist in (form?)
Definition
spherical= COCCI(single,chains, clusters, or cuboidal packets)
rod like= BACILLI (single or chain)
Term
staphylococci
Definition
clusters
Term
streptococci
Definition
chains
Term
sarcinae
Definition
cuboidal packets
Term
do bacteria have cell walls?
Definition
yes, except mycoplasma which does not
Term
mycoplasma
Definition
a bacteria that doesn't have a cell wall
Term
cell walls are composed of ___________
Definition
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)
Term
what do you call 4 amino acids joined by peptide bonds, and where would you find one
Definition
a tetrapeptide
the cell wall
Term
what are the two types of bacterial cell walls
Definition
gram negative and gram positive
Term
gram positive
Definition
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)
Term
which has porins? gram negative or gram positive
Definition
gram negative because it has the outer membrane which can have porins
Term
which has a thick layer of peptidoglycan, gram - or +
Definition
+
Term
gram positive appears
Definition
purple
Term
gram negative appears
Definition
pink
Term
gram negative
Definition
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
Term
what is the structure of a gram negative cell
Definition
-it has a thin cell wall/ layer of peptidoglycan
- it has an extra layer outside the cell wall (this layer is composed of two layers)(inner layer is phospholipids and proteins, outer layer is lipopolysaccharide.LPS or endotoxin)
Term
what is the outer layer of gram negatives extra outer membrane?
Definition
it is the LPS layer, or endotoxin layer (lipopolysaccharide) that contains lipid A which causes fever, vasodilation, inflammation, shock, and bloodletting
Term
why is gram negative bad
Definition
because when you kill large amounts of gram negative bacteria a lot of lipid a is being released from the outermsmbrane LPS/endotoxin layer.

- the gram negative outer membrane can also stop chemicals from passing through like penicillin.
Term
what is in the inner membrane layer of the extra membrane of gram negative cells
Definition
phospholipids and proteins
Term
what extra chemical does gram positive bacteria have?
Definition
teichoic acids
Term
techie acids covalently link to lipids and form
Definition
lipoteichoic acids
Term
what do lipoteichoic acids do
Definition
anchor peptidoglycan
Term
the periplasmic space contains
is this in gram neg or pos
Definition
gram neg

it contains peptidoglycan and periplasm
Term
mycobacterium
Definition
-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
Term
acid fast bacteria are from the __________ species
they have ______ which makes them hard to stain
Definition
mycobacterium
waxy lipid
Term
cytoplasmic membrane
Definition
- cell membrane, plasma membrane
- phospholipid bilayer
-fluid mosaic model
-selectively permeable
-proteins allow things to pass by acting as transport or channels
-interior of cell is more electrically negative that outside
Term
__________charged substances tend to be attracted into cells
Definition
positively
(because the cell is negative so it attracts positive)
Term
solute
solvent
Definition
solute- salt
solvent-water
Term
osmosis
Definition
diffusion of water across a semipermeable membrane until equilibrium is reached or until the pressure of water is equal to the force of osmosis
Term
isotonic
hypertonic
hyptonic
Definition
isotonic- when 2 solutions on either side of the PM have the same concentration of *solutes* the two solutions are said to be isotonic.

hypertonic- when the concentration of solutions(the amount of solutes within the solvent) are unequal the solution with the higher concentration of solutes is said to be hypertonic to the other

hypotonic- when the concentration of solutions are unequal, the solution with the lower concentration of solutes is said to be hypotonic to the other
Term
when thinking about isotonic, hypertonic, hypotonic, think about which has higher or lower concentration of __________

in biology these terms are used relative to the _________ of the cell
Definition
solutes (salt)

interior of the cell ***
Term
most cells are ________ to their environment
Definition
hypertonic
Term
cell placed in hypertonic solution (hypertonic to inside of cell so it has more solutes in the solution) it will__________
Definition
shrivel, lose water
Term
if a cell is placed in a hypotonic solution it will
Definition
swell, gain water
Term
what does cell wall help in regards to osmosis?
Definition
cell wall serves as a means to resist further osmosis and prevent cells from bursting
Term
cytoplasm is also called _______
it contains
Definition
cytosol
ions, amino acids,aqueous solution
Term
ribosomes
Definition
-protein synthesis
-translation
-in prokaryote all ribosomes exist in cytoplasm
-ribosome smaller in prokaryote
Term
how are ribosomes different in prokaryote
Definition
they are smaller and all located in the cytoplasm
Term
internal structures of prokaryote
Definition
cytoplasm (required)
ribosomes (required)
genetic material (requires)
endospores (optional)
Term
the genetic material in a prokaryotic cell is
Definition
a single, circular chromosome (in nucleoid region)
Term
endospores
Definition
- bacillus or clostridium (both human pathogens)
-bacterial cells that are metabolically active are called vegetative cells, these cells produce endospores which are metabolicaly dormant
Term
bacterial cells that are metabolically active
Definition
vegetative cell
Term
cells that are metabolically domarnt
Definition
endospores
Term
based on how the endospore is made, the end result is very resistant to ?
Definition
dehydration, heating, freexing, UV light
Term
endospores are very
Definition
resistant!
Term
sporulation
Definition
the process of making an endospore ( which protects chromosome so it isn't destroyed)
Term
when does sporulation take place
Definition
when their is a lack of needs/unfavorable circumstances such as a lack of nutrients or water cause sporulation in order to survive
Term
is the process of sporulation reversible?
Definition
yes, endospores may be converted back to the vegetative state (this is called germination) this happens when unfavorable circumstances are removed
Term
the reverting of an endospore back to the vegetative state is called
Definition
germination
Term
4 things all cells have:
Definition
cell membrane, cytoplasm, genetic material, ribosomes
Term
cocci-
bacilli-
vibrio-
spirilli-
spirochete-
Definition
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
Term
you should give _______ solution for dehydration
Definition
isotonic
Term
if blood cells are shriveled what is the explanation
Definition
a hypertonic solution must have been given
Term
if the cell was intact, which environment would that cell be able to survive?
Definition
hypotonic
Term
true or false, gram negative never has cross linking?
Definition
false, gram negative may have some cross slinking just not ever as much as gram positive
Term
how does penicillin work
Definition
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
Term
which have phosphoolipids in the cell membrane? gram positive or gram negative?
Definition
both
Term
which bacterial infections are harder to treat? positive or negative?
Definition
negative
Term
sketch gram positive and negative cell walls
Definition
Term
***ARE LIPOPROTEINS IN GRAM + and -???
Definition
Term
mycobacterium is gram _______ and ________ acid is also found in the cell wall
Definition
gram positive
mycolic acid
Term
for bacteria the cell wall provides protection from osmosis but only if it is in a __________ environment
Definition
hypotonic
Term
endospore is an internal structure unique to
Definition
prokaryotes ( but not all can produce the)
Term
what are the two families of endospore we are interested in
Definition
bacillus and clostridium (human pathogens) naturally found in soil, typically in the endospore state where would easily encounter them.
Term
________ is produced through the process of sporulation
Definition
endospore
Term
one __________ cell (a metabolically active state) produces one endospore
Definition
vegetative
Term
the process of ___________ returns one endospore back to the sensitive, vegetative state.
Definition
germination
Term
anthrax
Definition
bacillus anthracis endospores put in envelopes and mailed and then inhaled
Term
archae lack
Definition
peptidoglycan in the cell wall
Term
bacteria and arachaea reproduce
Definition
asexually
Term
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
Definition
is a complex polysaccharide
repeating subunits of NAG, NAM
tetrapeptides
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