Bacte Lec Quiz 2 - Bacterial Cytology Flashcards
describe the chromosome in DNA
single, circular, appear as diffuse, nucleiod or chromatin body
sac-like structure w/in cell membrane
mesosome
– found free in cytoplasm attached to cytoplasmic membrane
- Bacterial ribosome
function of granules
food storage
component of granules (2)
polysaccharide like glycogen
lipids such as poly-β- hydroxybutyrate or polyphosphate
– special name of granules of Corynebacterium
*Babes Ernst bodies/ granules
- special name of granules of Mycobacterium
*Much granules
cytoplasmic cell structures (4)
DNA, bacterial ribosome, granules, endospores
– resistant, highly refractive bodies within cell
- unstained areas or stained with specific spore stains
- function: resistant/protective structure
Endospores
component of spores:
calcium dipicolinic acid
cell structure not destroyed by boiling
endospores
cell structure that will germinate into another bacterium under favourable conditions
endospores
function of endospores
ensure bacterial survival in harsh conditions
causative agent of anthrax
Bacillus anthracis
– spore in spore strip for sterilization using oven
*Bacillus subtilis var niger
– spore spore in spore strip for sterilization using autoclave
*Bacillus stearothermophilus
components of cell membrane
phospholipids & proteins and NO STEROLS
function of cell membrane
regulates transport across membrane
acts as an osmotic barrier
enzyme regulation
functions of cell wall
maintains shape
prevents bursting of cell
components of cell wall
peptidoglycan
teichoic acids
lipids
type of teichoic acids that provide rigidity
lipoteichoic acids
components of Gram + cell wall
thick peptidoglycan
teichoic acids
components of Gram - cell wall
thin peptidoglycan
outer membrane
component of outer membrane
protein, lipid, LPS
Functions of Outer Membrane:
Barrier for hydrophobic compounds
Acts as sieve through pores
Attachment sites
type of cell wall
contain waxy layer and fatty acid (Mycolic acid – responsible for hard staining)
Acid Fast Cell wall
species which lack cell wall but they have sterols
-Gram staining & acid fast stain not useful
Mycoplasma and ureaplasma
surface polymers (3)
capsule, slime layers, glycocalyx
type of surface polymer discrete organized covering
-act as virulence factors - prevents phagocytosis
Capsule
components of capsule (2 poly)
polysaccharide, polypeptides
function of capsule
prevents or evades phagocytosis
ex of encapsulated bacteria:
Klebsiella pneumoniae or Diplococcus pneumoniae
-encapsulated organisms best viewed using ??? stain
negative stain
-more diffused surface polymer
Slime layers
function of slime layer
- inhibit phagocytosis
- aid in adhesion to host tissue
surface polymer: tangled mass of thin polysaccharide
Glycocalyx
function of glycocalyx
-aid in adhesion to host
cell appendages
flagella
pili (fimbriae)
component of flagella
protein
flagella is only found in
bacilli, NOT IN COCCI
term: no flagella
atrichous
term: one flagella
monotrichous
term: flagella at one or both ends
amphitrichous
term: multiple tufts at one end
lophotrichous
term: occur on all sides of bacterium
peritrichous
flagella may contain ??? properties
antigenic
antigens mentioned (4)
V, K, H, O
antigen from cell wall
O antigen
somatic antigen
O antigen
Ag from flagella
H antigen
Ag from capsule
K antigen
cell appendages are made of
protein
cell appendage: hairlike protein structures,
Pili (fimbriae)
pili function
aid in attachment to surfaces
2 types of pili
sex pili
adherence or ordinary pili
function of sex pili
reproduction: bacterial conjugation and gene exchange, for reproduction
function of adherence or ordinary pili
allows bacteria to attach to specific eukaryotic host cells (for attachment)
organism with sex pili
Neisseria gonorrhoeae
stain used for Cryptococcus neoformans
Negative stain
stain that stains background, not bacteria
Negative stain
stains used in negative stain
nigrosin dye
india ink
dye usually used for CSF to detect Cryptococcus neoformans
India ink
