Bacteria kingdom characteristics

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1. Bacteria kingdom Characteristics Simplest organisms: Very small size. Lack membrane-bound organelles inside the cell have few internal structures that are distinguishable under a microscope. genetic information is in a circular loop called a plasmid ( instead of having chromosomal DNA) Strong cell walls: resistant to environmental changes

2. Transformation bacteria incorporate genes from dead bacteria Transduction viruses insert new genes into bacterial cells. This method is used in biotechnology to create bacteria that produce valuable products such as insulin

3. Movement Flagella ~ Tail like structure the whips around to propel the bacterium Cillia ~ Miniature flagella surround the cell that help to “swim” Non motile ~ Sticky cillia like structures that keep the bacterium from moving

4. Movement Some prokaryotes can't move, while others have long threadlike flagella. If bacteria doesn’t move, how does it get from person to person?

5. Flagella

6. Cellular Walls Chemical nature of a cell wall can be determined by Gram Staining By finding out what color the cell produces when it is gram stained you can figure out the type of carbohydrates in the cell wall

7. Gram + and Gram – Bacterium Cell Walls

8. Gram-Positive Bacteria The cell wall has a thick layer of peptidoglycan 20 to 80 um thick 60-90% of the cell wall is peptidoglycan Except for the strptococci most gram positive bacterial cell walls contain very little protein Gram-negative Bacteria The wall of a Gram-negative bacterium is thinner but more complex than a Gram-positive bacterium Only10 to 20 % of the cell wall is peptidoglycan - the remainder consists of various polysaccharides, protein, lipids The cell wall contains an outer membrane- the LPS 8