rigid with a spiral/corkscrew shape (speralyavidniy)
flexible with a piral shape
two cells (pairs) of cocci or baccilli
cube of 8 cocci cells
clusters of cocci cells
chains of cocci cells or bacillus cells
square/rectangular shaped cells
bacteria that do not change shape withing the same species.
different shapes within one species
between rod and circle
- sugar coat
- Composed of polysaccharide and or polypeptide
- Can be used as energy source
- protects against dehydration
- Keeps nutrients inside the cell
3 types of Glycocalyx - the outer layer to the cell wall of bacteria
- Slime layer
- Extracellular polysaccharide
- glycocalyx neatly organized and is firmly attached to the cell wall
- Prevent phagocytosis by the host's immune system
A slime layer
glycocallys that is unroganized and is loosely attached to the cell wall
Extracellular polysaccharide (EPS)
is a glycocalyx made of sugars and allosw bacterial cells to attach to various sufraces.
- tails for moving, made of flagellin.
- Anchored withing the cell wall
- tists on its axis-rotates - run and tumble
Monotrichous - arrangment of flagella
one flagella on one end
one flagella at each end of the cell
2 or more flagella at both ends of the cell
many flegella over the entire cell
cell moving to or away from chemical (stimuli)
moving to or away from light
- partially inside the cell
- in Spirochetes - move like corkscew
- shorter, straighter, thinner than flagella and not used for movement.
- Used for attaching to surfaces to form biofilm
- only 1 or 2 per cell
- Trasfer DNA from one bacterial cell to another
- se pilli
Prokaryotic Cell Wall
- gives strucutre to and ptorects the cell - surrounds the underlyiing plasma membrane
- Prevents somotic lysis
- Cell wall is the site of action for some antibiotics
- Made of Peptidoglycan
Peptidoglycan of a cell wall
- NAG & NAM -monosacharide linked together(disaccharide) and they repeat
- These disaccharides linked togheter by polypeptides (chains of amino acids) to form lettice surrounding the cell.
- Penicillin inhibits polypeptide formation.-leads to cellular lysis
Cell wall of Gram-positive bacteria
- Many layer of peptidoglycan
- Teichoic acid - stick to wall of peptidoglycan layer
- Lipoteichoic acid links to palsma membrane
Cell wall of Gram-negative Bacteria
- Thin peptidoglycan layer between the outer phospholipid bylayer and inter phospolipid bilayr in plasma membrane.
- Outer layer
Periplasm in Gram-
- where peptidoglycan found
- contains many digestive enzymes and trasport proteins
- No teichoic acid - more susceptibale to rupture than Gram +
Outer membrane of Gram - cell wall
- lipopolysaccharides - phospholipid by-layr
- Contains porins - trasport proteins - makes outer membrane permeable
- Lipid A - endotoxin - can cause shock, fever.
digests the disaccharides in peptidoglycan
inhibits the formation of peptide bridges in peptidoglycan
Gram positive cell whose cell wall has been destroyed, but that is still alive and functional(lost its peptidoglycan)
wall-less Gram-negative cell(lost outer membrane and peptidoglycan)
wall-less cells that swell into irregular shapes.They can live, divide, and may return to a walled state.
phospholipid bilayer - basic famework of the plasma membrane. All the metabolic machinary - photosynthesis, aerobic respiartion, anaerobic resperaiton reactions.
3 type of proteins whithin the phospholipid bilayer
- Peripheral proteins
- transmembrane protein
- on top of membrane
- structural proteisn
- some assist the cell in changing membrane shape
Integral proteins transmembrane proteins
throught the plasma membrane - channels for movement of material into and out of the cell
Fluis Mosaic Model
- Plasma membrane is as viscouse as olive oil
- Phospholipids rotate and move alterally for proteins to work properly ex. changes shape.
Plasma membrane and its selective permeability
- allows the passage of some molecules but not others across the plasma membrane
- Ions pass slowly
- lipids easily
- water, oxygen, carbon dioxide, some simle sugars pass easily
chromotophores or thylakoids found of foldings of cells that rquired photosynthesis.