Bacteria NotesPage 266

Bacteria:• Prokaryotes, so single-

celled organisms without nucleus and other organelles like mitochondria

Flagella: •A long, whip-like structure that helps the cell move

Size and Shape:•Vary in size• Spherical

(cocci)

•Rod-like (bacilli)

• Spiral (spirochete)

Food • Some are autotrophs (make food from sun or chemicals) and some are heterotrophs (consume other food)• When your milk or meat spoils, it’s

because a heterotroph has been eating it!

Gram Staining

• A chemical process to classify different bacteria• Gram + have thick peptidoglycan and 1

membrane• Gram – have thin peptidoglycan but 2

membranes

E. Coli (-) and S. aureus (+)