Prokaryote:
-___ circular chromosome, not in a membrane (nucleoid)
- no histones
- no organelles
-_______: peptidoglycan cell walls
-_______: pseudomurein cell walls
- divides by _____ ______
One
bacteria
archaea
binary fission
Eukaryotes:
-_____ chromosomes, in nuclear membrane
-histones (to help bind DNA)
- organelles encompassed by membranes (Golgi, ER, mitochondria, lysosomes- imp. to immune system)
- _____________ cell walls (chitin in fungi)
- divides by ______
- meiosis for making sperms/eggs
paired
polysaccharides
mitosis
What can identify if a bacteria is an enemy?
shape
Bacterial Cells:
- average size : ______
- most bacteria are monomorphic (single shape)
- a few are pleomorphic (many shapes)
- bacillus (rod-shaped) and coccus (spherical-shaped)
spiral 3 shapes?
0.2 to 2.0 micrometers
diameter x 2 to 8 um length
spiral: vibrio, spirillum, spirochete
The Arrangement of Bacterial Cells:
- Pairs: _____cocci/bacilli
- Clusters: ______cocci
- Chains: _______cocci/bacilli
- Groups of four: _______
- Cubelike groups of eight: ________
diplo;
staphylo;
strepto;
tetrads;
sarcinae
glycolcalyx
Polysaccharide components lying outside the outer membrane of gram-negative cells or the peptidoglycan layer of gram-positive cells
external to cell wall
- viscous and gelatinous
- made of polysaccharide (sugar coat) and/or polypeptide
- Two types:
1. capsule: easily to be seen, what can resist the stain
2. slime layer: easily deforms, loose, unorganized - contribute to virulence: capsules prevent phagocytosis; extracellular polymeric substance helps form biofilms
phagocytosis
Your immune cells take up (eat) a bacterium.
After the bacterium is phagocytosed, immune cells use lysosomes containing digestive enzymes to kill the bacterium
Flagella:
- Filamentous appendages external of the cell
- Propel bacteria; provide ______
- 3 parts?
motility
- Filament: outermost region
- Hook: attaches to the filament
- Basal body: consists of rod and pairs of rings; anchors flagellum to the cell wall and membrane
How many basal bodies does a gram negative bacteria have vs a gram positive bacteria?
gram + : 4 because of 2 layers
gram - : 2 because of 2 layers
arrangements of bacterial flagella
- Amphitrichous
- Peritrichous
- Monotrichous
- Lophotrichous
run forward: ____
tumble: ______
counter-clockwise
clockwise
Flagella proteins are _ _____ and distinguish among ______
name a dangerous strain of E. coli?
H antigens
serovars
Escherichia coli O157; H7
E. coli O157:H7:
what is H7? what problem/disease does it cause?
H7 = flagella component
-produces toxins that cause infection
Axial filaments:
- also called _______ (under flagella’s membrane)
- embedded underneath outer membrane
- found in spirochetes (spiral shape)
- anchored at one end of a cell
- rotation causes cell to move like a corkscrew
endoflagella
How does the movement provided by axial filament help the bacterium?
helps bacterium penetrate mucus layers
*rotation + movement
Fimbriae and Pili:
-structures _______ bacteria
-fimbriae= hairlike appendages (made by proteins) that allow for attachment; biofilm formation; attach to epithelial cells of hosts in E. coli O157:H7
^why is it bad?
-pili: (similar to flagella) nano-machine consists of multiple proteins, involved in motility (gliding and twitching), ________ pili involved in ___ _____ from one bacteria cell to another (can spread antibiotic resistance)
outside
it’s bad because E. coli O157:H7 has fimbriae that helps attach to other healthy bacteria -> infects healthy cells
conjugation; DNA transfer
Cell Wall in Bacteria:
-prevents osmotic _____ and protects the cell membrane
-made of ________ and other macromolecules in bacteria
-contributes to pathogenicity (the ability to cause disease)
lysis
peptidoglycan
peptidoglycan:
-made of?
-rows are linked by?
protein and sugar
polypeptides (amino acids)
*maintains shape
