Prokaryotic Cell Morphology Flashcards
What are the different shapes of prokaryotic cells?
- Coccus: spherical
- Bacillus: rod-shaped
- Spirillum: spiral-shaped
- Spirochetes: tight corkscrew
- Budding: appendages
- Filamentous: strand-like
- Vibrios: comma-shaped
What are the different arrangements of prokaryotic cells?
- Staph-: clusters
- Strep-: chains
- Diplo-: pairs
- Sarcina: 3D formations
- Palisades: upright
What are the components of the cell wall?
- Peptidoglycan layer
- Teichoic acids
- Lipids
- Outer membrane
- Periplasmic space
Differentiate G+ and G- organisms based on the cell wall
G+ organisms have a thick peptidoglycan layer, usually has teichoic acids, small amounts of lipids, no outer membrane, and no periplasmic space
G- organisms have a thin peptidoglycan layer, no teichoic acids, lipids in the lipopolysaccharide layer, an outer membrane, and periplasmic space
What are the components of the peptidoglycan layer for G+ organisms?
N-acetylmuramic acid
N-acetylglucosamine
L-Alanine, D-Glutamic acid, Lysine, D-Alanine
beta-1,4-glycosidic bonds
pentaglycine cross-links
What is the structure of pseudomurein?
N-acetylglucosamine
N-acetyltalosaminuronic acid
beta-1,3-glycosidic bonds
L-Ala, L-Glu, L-Lys
What are the linkages present in the phospholipid bilayer?
Ester linkages
What are the linkages found in the Archael plasma membrane?
Ether linkages
Differentiate between the Bacterial plasma membrane and the Archaeal plasma membrane?
Bacteria: phospholipid bilayer, ester linkages, true fatty acids and glycerol heads
Archaeal: lipid monolayer, ether linkages, repeating isoprene units
What are the functions of the plasma membrane?
Permeability barrier Protein anchor Attachment site of bacteriophages Energy conservation Biosynthesis of other cells
What are the G+ organisms associated with endospore formation?
Bacillus anthracis
Clostridium botulinum
What are axial filaments?
Endoflagella
Give two examples of organisms with axial filaments?
Treponema sp.
Pallidum sp.
What are the two types of microbial taxes?
Chemotaxis: response to chemical signals
Phototaxis: response to light
What is glycan tetrapeptide?
Repeating unit of the peptidoglycan layer
Differentiate the peptido linkages in the peptidoglycan layer of G+ and G- organisms
G+: Lysine connects to D-Alanine via a pentaglycine cross-link
G-: DAP connects to straight to D-Alanine
Which sugar is the tetrapeptide linked to in the peptidoglycan layer?
N-acetylmuramic acid
Which sugar is the tetrapeptide linked to in the archael cell wall pseudomurein layer?
N-acetyltalosaminuronic acid
What is the function of the outer membrane?
Helps the passage of Ca2+ and Mg2+ ions
What are the components of the periplasmic space?
Hydrolytic enzymes
Binding proteins
Chemoreceptors
What are the 3 lipids found in the lipopolysaccharide layer found in G- organisms?
Lipid A
Core polysaccharide
O-polysaccharide
Give 3 organisms that have fimbriae
Salmonella sp.
Neisseria gonorrhoeae
Bordetella pertussis
