Bacteria

Bacteria

• tiny prokaryotic single-celled organisms

• only 1 chromosome

Bacteria Structure

• Peptidoglycan Cell Wall

• Plasma Membrane

• Cytoplasm

• Free floating chromosomes of DNA

• Ribosomes (produces chromosomes)

• Flagella

• Pili

• Capsule

• Endospores

• Plasmid

Plasmid

• A small circular DNA molecule separate from chromosomal DNA that can replicate independently

• Transferable

• Contains antibiotic resistance genes

Flagella

Allows bacterial movement

Pili

• Enables attachment to surfaces

• Short hair-like

• Allows DNA transfer during conjugation

Capsule

• Thick non-protein protective coats

Endospores

• Tough coated structures containing complete bacterial chromosome

• Tolerates dryness, extreme temperatures

• Can spread poisonous chemicals

Form and Arrangement

How a bacterial looks

Bacterial Forms

• Shape of bacteria

• Includes: Coccus, Bacillus, Spirillum

Coccus

Sphere-shaped cell

Bacillus

Rod-shaped cells; typically solo, pairs, or chains

Spirillum

Long curved shaped cells; mostly pathogens and in a single arrangement

Vibrio

Bean-shaped, subtype of Bacillus

Spirochete

Spring-shaped cells

Streptococcus

Chain of cocci

Tetrad cocci (Cocci in Tetrads)

2×2 cocci

Staphylococcus

Grape-like cluster of cocci

Sarcina

2×2 box like cocci