chapter3 Flashcards
T/F All bacterial cells possess a call wall
F : MOST exception (Mycoplasma (genus)) have none
T/F All bacterial cells possess cytoplasmic membrane
TRUE
DNA packing: Bacteria lack ____ and _____
nucleus and histones
T/F all bacteria cells possess a glycocalyx sugar coat
F : MOST do
prokaryotes cell wall is made of ______
petidoglycan
T/F Bacterial cells lack ribosomes and other membrane bound organelles
F : they lack membrane bound organelles but HAVE ribosomes
T/F bacterial cells have no endoplasmic reticulum
T : they lack membrane bound organelles
T/F ALL bacteria possess Flagella
false SOME
T/F ALL bacteria possess pili
FALSE SOME
T/F All bacteria contain cytoplasm
true
T/F All bacteria contain ribosomes
true
T/F All bacteria contain cytoskeleton
true
T/F All bacteria contain one or a few chromosomes
true
T/F All bacteria contain an outer membrane
false - some
T/F all bacteria contain nanowires/nanotubes
false - SOME
what are nanowires/nanotubes
very small structure extensions that allow bacteria to transport nutrients, electrons onto surfaces or other bacteria
T/F All bacteria contain plasmids
false- some
T/F all bacteria contain inclusions
false - some
T/F All bacteria contain endospores
F - some
T/F All bacteria contain microcompartments
false - some
what are micro-compartments
little aggregates of proteins stock pile enzymes etc in cytoplasm
Whats a Pleomorphic Genus bacteria
pleomorphic refers to organisms, particularly bacteria, that can have multiple shapes or forms. Instead of being a single, consistent shape, pleomorphic bacteria can vary in size and shape depending on their environment or growth conditions. This characteristic helps them adapt to different environments.
Example of pleomorphic Genera (5)
Mycoplasma, Rickettsia, Chlamydia, Corynebacterium, Haemophilus
what genus lacks a cell wall
Mycoplasma
Rickettsia and Chlamydia genus are gram + or -
gram -
Haemophilus is gram - or +
gram +
Haemophilus is what shape and arrangment
cocobacillus
bacteria function as independent single-celled _____ organisms
unicellular
whats biofilms
unicellular bacteria that act as a group are called colonies
what do nanotubes allow bacteria to do
some bacteria communicate through
baceteria have an average size of
1um (micron)
1 um = ? mm
1000 Um = 1 mm so 1um = .001 mm
cocci have a circumference of
1um
rods have a length of ___ and width of ___
length = 2um and width = 1um
example of pleomorphism
if left in incubator too long, used up all nutrients, cells would start to look different, change
variations in cell wall structure caused by slight genetic or nutritional diffrences
pleomorphism
If the cell is spherical or ball-shaped, the bacterium is called :
coccus/cocci
staphy refers to arrangment
clusters, also a genus
A cell that is cylindrical is termed
rod or bacillus
T/F bacillus is only a cellular shape
No also a genus Bacillus
T/f staphy is also a genus
True : Staphy
T/F Rods are not varied in their forms.
False: very varied based on species, blocked, sindle-shaped, round-ended, long adn thredlike (filamentous) or club shaped, drumstick - shaped
what are bacillus that are short and plump called?
coccobacillus
What bacterium is this and what is it called shape wise
cocobacillus - Legionella pneumophila
A bacterium having slightly curled or spiral shaped, corkscrew body is called
Spirillum
what bacterium is this and shape
spirillum, Campylobacter jejuni, usually found in aquatic environments, also human pathogen
what bacterium is this and shape
vibrio shape, called: Vibrio vulnificus, (gram -)
what bacterium is this and shape
spirochete, corkscrew shape
bacteria: spirochetes (gram -)
what gram is vulnificus
gram -
what gram is spirochete
gram -
what shape is vibrio
curved rod
what shape is spirochete
corkscrew
difference between spirillum and spirochete?
spirillum:
shape - rigid, corkscew
flexibility - stiff
movement - move with flagella at both ends
Spirochete:
shape- spiral but thinner and longer
flexibilit - super flexible
movement: move using periplasmic flagella
bacteria that produce multiple branches off a basic rod structure are called
filaments
What bacteria and shape is this
Streptomyces (gram +) shape: filament
diplococci
pairs
tetrads
groups of 4
streptococci
chain
staphylococci or micrococci
irregular clusters (grape like)
sarcina
cubal packet of 8, 16 or more
what are these bacterial arrangments
diplococci and streptococci
what bacterial arrangments
Tetrads and sarcina
what bacterial arrangment
staphylococci
bacterial shape and arrangement
bacilli and palisades: cells of a chain remain partially attached by small hinge region at ends
Corynebacterium is what shape and arrangement
bacilli and palisades
whats palisades arrangement
cells of a chain remain partially attached by small hinge region at ends
Corynebacterium is what gram + -
gram +
Which of the following are possessed by some but not all prokaryotes?
A. Ribosomes
B. Cell membrane
C. one or more chromosomes
D. Flagella
Flagella
T/F spirilla are always found in short chains
false, occasionally
T/F spirochetes rarely remain attached after cell division
true
____ have an internal flagellum called endo or periplasmic flagelum
spirochetes
what is a polar arrangement of flagella?
Flagella attached at one or both ends of the cell
monotrichous (flagella arrangment)
(polar arrangement) one single flagellum
Lophotrichous (flagella arrangment)
(polar arrangement) small bunches or tufts of flagella emerging from the same site
amphitrichous (flagella arrangment)
(polar arrangement) flagella at both poles of the cell
Peritrichous (flagella arrangment)
flagella dispersed randomly over the surface of the cell
atrichous(flagella arrangment)
absence of flagella
chemotaxis
movement of bacteria in response to chemical signals
Negative chemotaxis
movement away from a reppelant
positivie chemotaxis
movement toward favorable chemical stimulus
Run
roation of flagellum counterclockwise, resulting in a smooth linear direction
tumble
reversal of the direction of the flagellum causing the cell to stop and change course
label the flagellar arrangements
monotrichous (single flagellum)
label the flagellar arrangements
peritritous
label the flagellar arrangements
Peri (flagella dispersed randomly over the surface of the cell)
label the flagellar arrangements
Amphitrichous (flagella at both poles of the cell
t/f eukaryotic cells are also capable of rotating flagella clockwise or counter
false, completely different structure
Fimbria
small, bristle like fibers sprouting off the surface of many bacterial cells
allow tight adhesion between fimbrae adn epithelial cells allowing bacterial to colonize and infect host (stick and adhere)
photo of
fimbria (stick adn adhere with tiny bristle like fibers)
Pilus/pili
can act as aconduite to transfer genes from bacteria cells to another
what type of pilus can transfer genetic material, act like fimbriae adn assist in attachment as well as make a bacterium motile?
Type IV pilus
_____ is used in conjugation between bacterial cells
pilus/pili
pilus and pili are well characterized in gram _ bacteria. Why is this?
gram negative bacteria, pilli often attach to outter membrane
very long, thing tubular extensions of the cytoplasmic membrane
nanotubes
nanotubes are used to
transfer amino acids, DNA nutrients between cells or to harvest energy by shuttling electrons
Conjugating process: _____ are longer than fimbriae bristles, the bacterial cell makes ____ and shoots it out to dock station of same species sends over some genetic material to recipient cell
pili
Where is the S layer in gram + vs gram -
in gram + it is cytoplasmic membrane, cell wall, s layer, glycocalyx,
in gram - it is cytoplasmic membrane, cell wall, outter membrane, s layer, glycocalyx
whats an s layer
Single layers of thousands of copies of a single protein linked together like tiny chain link fences
Only produced when bacteria are in a hostile environment
glycocalyx made of
Coating of repeating polysaccharide or glycoprotein units
- sugar coating
(slime layer and capsule)
slime layer
loose, protects against loss of water and nutrients ,can make it more difficult to be ingested but not the same as a capsule
capsule
loose, protects against loss of water and nutrients
two types of glycocalyx
slime layer and capsule
image of encapsulated bacteria using ____ stain and ____ stain to show capsule
gram + and gram -
when you look at colonies that have mucoid or sticky texture they are called ____ _____ and usually capsulated cells.
smooth colonies. Other wise they are rough colonies and no capsule.
why have a glycocalyx
- assists in adhesion adn formation of biofilms
- keeps in nutrients and water
- protects from immune system greater pathogenic ability
explain the relationship between glycocalyx and biofilms
The glycocalyx contributes to the formation of biofilms by providing a protective and adhesive layer, helping microorganisms stick to surfaces and to each other. So while biofilms contain glycocalyx materials, they are broader structures formed by communities of cells rather than just a singular glycocalyx layer.
example of biofilms
plaque on teeth, protect bacteria from becoming dislodged,
resposible for persistent colonization of plastic catheters, IUDs, adn other implanted medial devices
Streptococcus pneumoniae is an example of ____ bacterial pathogen
encapsulated
gram +
streptococcus
Klebsiella pneumoniae
encapsulated pathogen
gram negative
rod
Haemophilus influenzae
encapsulated pathogen
Gram negative
coccobacillus
Pseudomonas aeruginosa
encapsulated pathogen
Gram negative
rod
Neisseria meningitidis
encapsulated pathogen
Gram negative
diplococcus
(gohnorea)
explain the steps of biofilm formation
what is included in the cell envelope?
Everything that lies outside of the cytoplasm (cell wall, cytoplasmic membrane, outer membrane (some))
composed of two or three basic layers that each perform a distinct function but together act as a single protective unit
what is a gram + cell
thick peptidoglycan layer no outer cell membrane (gram +, holds purple dye)
what is a gram - cell
thin peptidoglycan layer, has outer cell membrane (gram -, does not hold purple, counter dye dye shows pink)
_____ _____ helps determine the shape of a bacterium
cell wall
____ provides structueral support to keep the bacterium from bursing or collapsing because of changes in osmotic pressure
cell wall
certain drugs target the ____ disrupting its integrity and causing cell ____ (rupture of the cell )
cell wall, lysis
cell wall gains rigidity from ___
peptidoglycan
pepridoglycan is composed of repeating frame work of long ___ chains cross-linked by short ____ fragments
glycan(sugar) chains, peptide(protein).
penacyline knocks ut enzymes that connect glycines together in ____ causing cell to lyse.
peptoglycan cell wall causign cell to lyse
whats the thickness fo gram + cell wall
20-80 nm thick
