Module 3 pt. 4 Flashcards
The Danish bacteriologist who devised the most frequently used differential stain
Hans Christian Gram
Gram stain
Primary stain
Mordant
Decolorizer
Counterstain
Crystal violet - primary stain
Iodine - mordant
95% ethanol - decolorizer
Safranin - counterstain
Used to fix bacteria sample to formation of a complex of crystal violet and KI
Mordant
Stain does not come out of which type of bacteria?
Gram positive bacteria
Kind of bacteria without cell wall
They have sterols in their cell membranes for stability
Mycoplasma species
Parts of a glycocalyx:
Less discrete structure or matrix which embeds the cell ; diffuse and irregular.ONLY called this when glycocalyx is LOOSELY BOUND
Discrete detectable layer of polysaccharides deposited outside the cell wall; distinct and gelatinous. ONLY called this when glycocalyx is TIGHTLY BOUND. Sharply defined, organized structure
Slime layer
Capsule
Capsules are ___, this contribute to VIRULENCE
Protects against ___
Help adhere to different surfaces like medical implants
Helps trap nutrients near the cell
Soil bacteria protected from dessication
Reserves for carbohydrates
Protect from engulfment
Antiphagocytic
LYSOZYME
Functions of Glycocalyx (5)
Disease - virulence
Protections - Protects from antibiotics, chemicals, white blood cells
Adherance to surfaces - attach to surface of the host
Avoidance of dessication - prevent dryness
In cell-cell recognition - receptors to bind to other cells of close species
The bacteria that uses its slime layer to accumulate on tooth enamel.
Streptococcus (Gram positive)
A polysaccharide-encased mass of bacteria coating a surface
BIOFILM
A common form of protein found in flagella
flagellin
Responsible for the motility of bacteria
Spins like a propeller
Termed the ‘H’ antigen.
Sometimes attach by immune responses
10 - 20 micrometers in length
Flagella
Rotation and rate of flagella
1500 rpm
rate 10 body lengths/second
A flagella is found in all motile bacteria except ___.
Spirochetes
Type of bacteria to have multiple flagella
Helicobacter pylori