Microbio: Bacteriology pt.2

Average size of prok. bacteria

0.2—>2.00 μm

3 basic shapes of bacteria

Spherical (round), Rod-Like, Spiral

Coccus (Spherical Bacterium)

Bacillus (Rod-Like)

Coccobacilli (shirt rod)

Comma shape/Vibrio

Spirillum pl.spirilla (rigid wavy)

Spirochete (Corkscrew shape)

Monomorphic (Most bacteria are monomorphic)

Bacteria that keep one consistent shape (don’t change form).

Pleomorphic

Bacteria that can change shape or size depending on conditions (environment, age, or stress).

Binary Fission

Division and Multiplication amongst Prokaryotes

Diplococcus

Groups of 2

Streptococcus

Chainlike formation

Tetrod

Group of 4; undetached cells

Sancinal

Group of 8; undetached cells

Staphylocacci

Group like function; Numerous groups

Appendage of Prok. cells

Outermost/external part

Hook

Short curved segment that links the filament to the basal body

Filament

Tail

Basal body

Attaches entire flagellum to the cell envelope

Atrichous Bacteria

Bacterial devoid without flagellum

Monotrichous

One flagellum (mono=1)

Amphitrichous

1 flagellum at both poles (Amphi= both poles)

Lophotrichous

Cluster of flagella at one end or both side (Lopho=cluster)

Peritrichous

Flagella are spread evenly around the cell (Peri=around)

Periplasmic/Endo-flagella

Flagella wraps around cell (associated with spirochete)

Pilus/pl. Pili

Short, fine, hair-like appendages. Not associated with locomotion (movement). (aprx.1000 pili per cell)

2 types of Pili

Attachment (Fimbriae) & Sex/Conjugation

Attachment (Fimbriae) Pili

Adhesion to surfaces

Sex/Conjugation Pili

Helps bacteria exchange genetic material (DNA) from cell A (Donor cell)—>B (Recipiant)

Cell envelope

All the layers that surround the cytoplasm of a bacterial cell (membrane(s) + cell wall).

Glycocalyx

Polysaccharide sugar coat lying outside of cell wall (2 types: Capsule & Slime layers)

Capsule

(Thick armor) Organized, not washed off easily and Protects bacteria from phagocytosis

Slime layer

(Sticky glue) Loose unorganized, easily washed off. Helps with attachment to surfaces

Phagocytosis

A process where a cell (phagocytes) engulfs and digests particles, such as bacteria.

Cell wall

A rigid layer that lies outside the plasma (cytoplasmic) membrane. Provides shape and protection for the cell. Site for antibiotics. peptidoglycan

Osmotic Lysis

Cell bursting from too much water (hypotonic)

Gram stain

To classify bacteria as Gram-positive or Gram-negative based on cell wall structure (peptidoglycan thickness).

Gram positive (q+)

Bacteria stained purple or blue; Thicker peptidoglycan layer

Gram negative (q-)

Bacteria stained red or pink; Thinner peptidoglycan layer