Bacteria - Gwinnett County Public Schools1].pdf2 Domains of Bacteria Archaea Bacteria Domain...
Transcript of Bacteria - Gwinnett County Public Schools1].pdf2 Domains of Bacteria Archaea Bacteria Domain...
2 Domains of Bacteria
Archaea Bacteria Domain (Ancient Bacteria)
• Live in extreme environments: without oxygen,ocean floors, salty water, hot springs, cow intestines,swamps.
Eubacteria Domain (True Bacteria)
• Live everywhere.• Cyanobacteria (blue-green algae) –contain chlorophyll, live in water, return nitrogen tothe soil; green pond scum
Characteristics of Bacteria
1. Unicellular = single-celled.
2. Prokaryotes: Cell DNA notcontained in a nucleus.
• DNA is circular shape.
3. Surrounded by a cell wall.
4. May have flagella to move.
Obtain Food
1. Autotrophs: make their food.
• Photosynthesis
• Use chemical substances in their environment.
2. Heterotrophs: cannot make their own food.
• consume other organisms.
• consume foods.
• consume dead organisms.
Respiration1. Break down food to release energy.
2. Some require oxygen = aerobes.
glucose + oxygen carbon dioxide + water + energy
C6H12O6 + O2 6CO2 + 6H2O + 36 ATP energy
3. Some do not require oxygen = anaerobes.
glucose lactic acid + energy
C6H12O6 2C3H6O3 + 2 ATP energy
Reproduce
• reproduction that involves only one parent• offspring are identical to the parent
Binary Fission: cell divides to form two identicalcells
1. Asexual Reproduction:
2. Sexual Reproduction:
• reproduction that involves two parents• offspring is different from both parents
Conjugation
• genetic information is exchangedbetween organisms
• does not increase the number of bacteria• results in bacteria that are genetically different
3. Endospore: a small, rounded, thick-walled,resting cell that forms inside a bacterial cellwhen conditions are not good enough toreproduce.
• helps bacteria survive harsh conditions byresisting, freezing, heating, drying
Pasteurization: food is heated to a temperature high enough to kill most harmful bacteria without changing the taste of the food.
5. Health and Medicine
• Help digest food in your intestines.
• Make vitamins your body needs,such as, vitamin K needed forblood clotting,
• Make medicine such as insulin.