bacteria
DESCRIPTION
Bacteria. From Bacteria to Plants Chapter 2.2 Pages 56-66. Discovery. Believed to be one of the earliest forms of life on Earth Undiscovered until the 1600’s Anton van Leeuwenhoek. Bact Basics. Bacteria are Prokaryotes : genetic material is not contained in a nucleus - PowerPoint PPT PresentationTRANSCRIPT
BacteriaFrom Bacteria to Plants Chapter 2.2
Pages 56-66
Discovery• Believed to be one of the earliest forms of
life on Earth• Undiscovered until the 1600’s– Anton van Leeuwenhoek
Bact Basics• Bacteria are
Prokaryotes: genetic material is not contained in a nucleus– Also lack many other
structures found in cells.
Shape & Structure• Most bacteria have Cell Walls, for protection• Also has…– Cytoplasm that contains genetic material– Ribosomes which produce proteins– Flagellum (flagella) a whip-like structure / tail
used for movement.
Shape & StructureThree basic shapes1. Spherical2. Rod-like3. Spiral shaped• These shapes help
us identify bacteria
Tale of Two KingdomsArchaebacteria
• “Ancient,” having existed for billions of years
• Live in extreme environments – Hot springs– High salinity– High acidity
Eubacteria• Original autotrophs
(produce their own food) that developed our atmosphere
• Live in all non-extreme environments– The surface of any object– On animals– Inside animals
Reproduction• Bacteria reproduce through process
called Binary Fission
• Cell copies its genetic material then divides into two separate cells.
By the Numbers• The average surface in your bathroom
contains about 6,000 bacteria per square inch
• Disinfectants claim to kill 99.9% of germs• This would leave 5 bacteria… not bad• However, average sink space is about 2
square feet – leaving 120 bacteria behind.
By the Numbers
• Under decent conditions, binary fission can take place every 30 minutes
• After an hour, each bacteria will reproduce 2x, creating 480 bacteria
• It will take only 3 hours to create 7,680 bacteria where there was only 5 before.
What to Work On
• Finish reading about Bacteria in your textbook, pages 56-65
• Working as a group, answer the section review questions on page 65 (#’s 1-5)–One answer page per group