Bacteria

1
Bacteria

• Lab 16

2
Bacteria

• Prokaryotes lack organelles.
• Bacteria are the simplest forms of life.
• Bacteria contain DNA, but it is not contained in
  a nucleus.
• Bacteria reproduce by fission they simply split
  in two.

3
Bacteria

• Most bacteria are saprotrophic they send out
  digestive enzymes into the environment and then
  take up the nutrient molecules.
• Some bacteria are parasitic and cause disease.

4
Bacteria

• Others are photosynthetic or chemosynthetic
  making organic (food) molecules from inorganic
  molecules.
• A colony contains cells that are all descended
  from one original cell.

5
Shapes of Bacteria

• Bacteria come in 3 shapes
• Bacillus (rod)
• Coccus (round)
• Spirillum (spiral)

Images by Biodisc company.
6
Bacterial Structure

• Basic structure includes a loop of DNA,
  ribosomes, a plasma membrane, a cell wall,
  sometimes a capsule.
• Some bacteria move about using a flagellum.
• Pili are used for attachment.