Micro-Bacteriology Flashcards
(40 cards)
What is the basic groups of bacteria?
1-cocci
2-bacili
3-spirochetes
What is name of bacteria that have many shapes?
Pleomorphic bacteria
The shape of bacteria dependent on
Rigid of ceel wall
Why microscopic apperanc of bacteria ismost important
Because it criteria in identification on bacteria type
Also an arrengement of the bacteria is important give an example about this
1-some bacteria (cocci) occur in pairs=diplococci
2-some occur in chain=streptococci
3-some occur in clusters=staphylococci
The arrengment of bacteria dependent on
Orientation and degreeof attachment during cell division
Bacteria rang in size from
0.2 to 5um
The smallest bacteria is
Mycoplasm that have the same size of largest virous (poxvirus
All bacteria have cell wall exept
Mycoplasm bacteria
Cell wall of bacteria comosed of
Peptidoglycans
What is the function of peptidoglycans
1-provide structural support to cell wall
2-maintaine the characteristic shape of cell
3-withstand of low osmotic pressure such as water
What are the diffrences between germ gpositive and gram - negative bacteria?
In strectuer and chemical composition and thickness of cell wall
Peptidoglycan layer is thickness in gram - positive bacteria than in gram-negative
Yes 👍😍
Gram - positive bacteria have fibers inthe that protrued outside peptidoglycan layer called
Teichoic acid
Gram - negative bacteria have comlex outer layer composed from
1-lipopolysaccharied
2-lipoprotein
3-phospholipied
Where the lipopolysaccharied located in gram - negative bacteria
Between outer membrane layer and cytoplasmic membrane in (periplasmic space
All the peptidoglycan and LPS and proteins and cell wall ;ribosome and porin proteins are considered
Antigens to antibiotics
What is the function of porin proteins in bacteria
Serve as channel to allow of sugers ;vitamins;amino acid ;metals and antimicrobial drugs such as panicilin to pass through it
What example about acid - fast bacteria
Mycobacterial tuberculosis
Acid - fast bacteria is called in this name because
It have an usual cell wall contain high consntration of lipid that called mycolic acid that resist decolorization with acid - alcohol after being stained with carbolfuchsin
Glycerol Teichoic acid that pentrait the peptidoglycan and attached with lipid in cytoplasmic membrane is called
Lipoteichoic acid
The stracture of peptidoglycan consist of three components
1-glycan sugers (NAM;NAG)
2-tetrapeptid chain
3-cross links (peptid interbridge)
Some of antimicrobial drugs attack peptid interbridge such as
Panicilin cephalosporinand vancomysin
LPS(endotoxin) responsiple for
1-some fetures of diseas such as fever and shock(hypotention)