Prokaryotes are widespread on Earth

Clicker Question!

• What kind of reproduction is depicted in the photo below?
• A: Asexual
• B: Conjugation
• C: Binary fission

• KEY CONCEPT Prokaryotes perform important functions for organisms and ecosystems.

Prokaryotes provide nutrients to humans and other animals.

• Prokaryotes live in digestive systems of animals.
• make vitamins
• break down food
• fill niches

Bacteria help ferment many foods.

• Bacteria help ferment many foods.

• yogurt, cheese

• pickles, sauerkraut
• soy sauce, vinegar

Bacteria make Medicine

• Vitamins
• Antibiotics:
• Streptomycin
• Bacitracin
• Tetracycline
• Vancomycin

Prokaryotes play important roles in ecosystems.

• Prokaryotes have many functions in ecosystems.
• photosynthesize
• recycle carbon, nitrogen, hydrogen, sulfur
• fix nitrogen

Bioremediation uses prokaryotes to break down pollutants.

• Bioremediation uses prokaryotes to break down pollutants.

• oil spills

• biodegradable materials

• KEY CONCEPT Understanding bacteria is necessary to prevent and treat disease.

Some bacteria cause disease.

• Bacteria cause disease by invading tissues or making toxins.
• A toxin is a poison released by an organism.

Normally harmless bacteria can become destructive.

• Normally harmless bacteria can become destructive.

• may colonize new tissues

immune system may be lowered

• immune system may be lowered

• Normally harmless bacteria can become destructive.