INTRO TO BACTERIOLOGY Flashcards
Bacteria are __karyotes
pro
Bacteria cells possess nuclei and organelles
T/F
F
They lack them
Bacteria range in size from about ___ to __ μm
0.2
5
Plasma membrane of prokaryotes contain sterols
T/F
Mention exceptions
F
Except mycoplasma species
Absence of nuclear membrane in prokaryotes
T/F
T
Genome of prokaryotes
Single or double
Linear or circular
Single
Circular
Prokaryotes have organelles
T/F
T
Just not membrane bound organelles
Ribosomes of prokaryotes and eukaryotes?
Pro- 70S (50+30)
Euk-80S (60+40)
Cell division of prokaryotes is by??
Binary fission
Bacteria are classified by shape into three basic groups:
*___
*_____
*___
Cocci
Bacilli
Spirochetes
Cocci (____)
Bacilli (___)
Spirochetes (_____)
round
rods
spiral-shaped
In addition to their characteristic shapes, the arrangement of bacteria is important.For example, certain cocci occur
* in pairs ( _______)
*some in chains(_______)
*some in grapelike clusters (_____)
diplococci
streptococci
staphylococci
Example of a rod shaped bacteria
Escherichia coli
3 Examples of a snake like shaped bacteria
Treponema
Borrelia
Leptospiral
Examples of a diplococci
Neisseria, moraxella
Example of a coccobacillus
Bordetella pertussis
-The bacterial “______” is a term applied to all material external to and enclosing the cytoplasm.
CELL ENVELOPE
CELL ENVELOPE
-It consists of several chemically and functionally distinct layers, the most prominent of which are the:
*_____
*______
*______
*______
Cell wall
Cytoplasmic membrane.
Capsule
Glycocalyx
CYTOPLASMIC MEMBRANE
-The cell membrane is composed of ______, the molecules of which form two parallel surfaces (called a lipid bilayer)
-The _____ groups are on the outside of the bilayer and the ______ are on the inside.
phospholipids
polar phosphate
nonpolar lipid chains
CELL WALL
-The cell wall is located (internal or external?) to the cytoplasmic membrane and is composed of _____.
External
peptidoglycan
The cell wall acts as a barrier, and protects cell contents from the external environment
T/F
T
The cell wall
Maintains cell osmotic pressure in a hypotonic environment
T/F
T
The cell wall Contributes to sensitivity to certain antimicrobial agents (penicillin) and the immune system (antibodies, phagocytes)
T/F
T
The cell wall doesn’t Determines reactivity to Gram stain
T/F
F
PEPTIDOGLYCAN
- is a complex, interwoven network that surrounds the entire cell and is composed of a single covalently linked macromolecule
T/F
-
T
PEPTIDOGLYCAN
-The basic structure consists of ______ chains with _______ or longer side chains that are cross-linked through ___ bonds.
polysaccharide (glycan)
tetrapeptide
peptide
PEPTIDOGLYCAN
The glycan chains are linear polymers of a repeating __saccharide composed of __________ and _______
di
N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM).
__________ , present in human tears and mucous secretions, cleaves glycan chains.
Lysozyme
GRAM POSITIVE CELL WALL
-Gram-positive bacteria have (thin or thick?), (single or multi?)layered, peptidoglycan cell walls that are (interior or exterior?) to the cytoplasmic membrane.
Thick
Multi
exterior
_____ and ____ acids associated with peptidoglycan are antigenic (strain differences) and may promote _______
Teichoic and lipoteichoic
adhesion to host tissue.
GRAM NEGATIVE CELL WALL
-Gram-negative bacteria have a (less or more?) complex cell wall structure composed of ___ membranes Which are separated by the _________ , which contains the (thin or thick?) peptidoglycan layer.
More
two
periplasmic space
Thin
The periplasmic space also contains ______ and ______
degradative enzymes and transport proteins.