BACTERIAL MORPHOLOGY, PHYSIOLOGY, AND CLASSIFICATIO Flashcards
General Characteristics of Bacteria
Minute unicellular organisms
Vary in shapes
Vary in size
Possess a cell wall
Multiply by Binary Fission
Collective term for the outer layer
CELL ENVELOPE
➢Outer membrane
➢ Periplasm
➢ Cell Wall
➢ Cell membrane
Bilayer
Cell envelope
Cell envelope of Gram (-)
Periplasm
Present in both Gram (-) and (+)
Cell membrane
Functions of Cell envelope
Acts as osmotic barrier
For energy generation
Hydrolytic enzymes
Biosynthetic function
Chemotactic system
Composition of Cell Wall
Peptidoglycan
Cell wall is common to all bacteria except?
Mycoplasma
Rigid layer that surrounds the cell membrane.
Vary in composition
Cell Wall
Functions of Cell wall
Rigidity
Protection against osmotic pressure
Contributes to pathogenicity
Site of antigenic determinants
Components of Gram (+) Cell wall
Peptidoglycan
Teichoic Acid
Types of Teichoic acid
Wall teichoic acid
Membrane teichoic acid
Cell wall linked to polypeptidoglycan
Wall teichoic acid
Cell wall linked to the cell membrane
Membrane teichoic acid
Wall less variants of normal cells. Wall-less due to chemicals and other factors.
L forms/phase Types
Protoplast
Spheroplast
Gram (-) Cell wall composition
Peptidoglycan
Outer membrane
proteins
bilayer of phospholipids
porins
Lipopolysaccharides
Lipoprotein
Gram (-) cell wall outer membrane composition
Proteins
Bilayer of phospholipids
Porins
Wall- less bacterium
Naturally occurring; resistant to antibiotics
Mycoplasma
plant cells that have had their cell walls removed by treatment with cellulytic enzymes
Protoplast
a microbial cell from which the cell wall has been almost completely removed, as by the action of penicillin or lysozyme
Spheroplast
Composed of polysaccharide
Surface adherents
GLYCOCALYX
Firmly attached to cell wall
Thick, well organized structure
Not easily washed off
Virulence factor
CAPSULE
Loosely associated with the cell wall
Diffused, unorganized layer
Easily washed off
Slime layer
Protection
For attachment or adherence to
other cell tissues on body cells
Resistance to phagocytosis
Glycocalyx
Arise from the surface of the bacterium
Cell Appendage
Types of Surface Adherents
Capsule
Slime Layer
Long, hair or whip like filamets
Flagella/flagellum
Composed of CHON known as FLAGELLIN
Flagella
Chon is known as?
Flagellin
Types of Flagellin
Atrichous
Monotrichous
Lophotrichous
Amphitrichous
Peritrichous
No flagella
Atrichous
Single Flagella
Monotrichous
Numerous flagella at one end
Lophotrichous
Numerous flagella at both end
Amphitrichous
Flagella all over
Peritrichous
Not involved in motility
Shorter than flagellum
PILIN
PILI OR FIMBRIAE
Types of Pili or Fimbrae
Ordinary or common pili
Sex pili
Transfer of genetic material from one cell to another cell which are in diret c ontact with each other
Conjugation
Found in Spirochetes
Axial Filament or Afibril
Modifiel Flagellum called as?
Endoflagellum
Enclosed in a cell and is responsible for motility of spirochetes
Endoflagellum
Dense gelatinous mass
70-80% water
Cytoplasm
How much percentage of water is the cytoplasm of bacteria?
70-80%
Cytoplasmic Structures
Ribosomes
Mesosomes
Granules or inclusion
Nucleoid
Plasmid
Spores
Can only be killed in autoclave
Cytoplasm of bacteria
Factors of resistance of Cytoplasm of bacteria
Spore rich in Calcium, Vitamin D and Dipicolinin Acid
Dehydrated state (15%)
Inert or inactive state
Block entry
Site of protein synthesis
Ribosomes
Invagination; site of DNA recognition
Mesosomes
Glycogen and polyposmic granules in cytoplasmic structure
Granules or inlucions
Contains DNA
nucleoid
Has genetic elements
Plasmid
Formed when bacteria at adverse physical and chemical conditions
Spores
Spore parts
Spore
Core
Cytoplasmic Membrane
Spore wall
Cortex
Keratin Spore coat
Thich layer of less cross-linked peptidoglycan in spore
Cortex