Bacteria

Eubacteria/Archaebacteria Live almost everywhere Surrounded by a cell wall Cell walls contain peptidoglycan Archaebacteria Lack peptidoglycan DNA is similar to eukaryotes

Prokaryotes Identified by shape, chemical nature of cell walls, way they move, and way the obtain energy Shapes: Bacilli = rod shaped, Cocci = spherical, Spirilla = spiral Movement: Propelled by flagella

Metabolisms Heterotrophs: Autotrophs: Chemoheterotrophs: get energy from organic molecules Photoheterotrophs: get energy from light Autotrophs: Photoautotrophs: Use light energy Chemoautotrophs: Organic molecules from CO2

Growth/reproduction Binary fission : cell splits into two cells Conjugation: Exchange of genetic information across cells Spores: makes bacteria inactive and well- protected

Importance Vital to maintaining the world Decomposers Nitrogen fixers Recycle nutrients Nitrogen fixers Make NH3 for plants to use

Web resources http://www.youtube.com/watch?v=rp7T4IItbt M http://www.youtube.com/watch?v=TDoGrbpJ J14

Viruses Particles of nucleic acid, protein, and in some cases, lipids Can ONLY reproduce by infecting other living cells Composed of a core of DNA or RNA surrounded by a protein coat Viruses protein coat: capsid Cell specific- binds to specific proteins on the outsides of cells Bacteriophage-virus that can infect bacteria

Lytic Infection Bacteriophage injects DNA into bacterium Bacteriophage DNA forms a circle Causes synthesis of new bacteriophage proteins and nucleic acids by taking over bacterium’s metabolism Newly created proteins and nucleic acids assemble into complete bacteriophage particles Bacteriophages break the cell wall and go to attack other cells

Lysogenic Infection-dormant Bacteriophage injects DNA into bacterium Bacteriophage DNA forms a circle Bacteriophage DNA inserts itself into the bacterial chromosome DNA replicates possibly for many generations Bacteriophage DNA exits bacterial chromosome and enters lytic cycle Lytic cycle

Other Facts Retrovirus: Only contain RNA as their genetic information-must produce a DNA copy of its RNA when infects a cell (Dormant for long periods of time) Viruses considered parasites for they live off of other cells to grow and reproduce NOT considered alive for they can’t survive independently Produce diseases by disrupting body’s equilibrium

Immune Response

How a pathogen enters and what happens next… A pathogen or foreign substance can penetrate into the body by entering through: cuts or gashes in the skin, mouth/nose (inhaling), and other open areas throughout external view of the body. Once a pathogen or foreign substance enters the body, an immediate process takes place called the immune response.

Types of immune responses The two types of immunity are: Humoral immunity- where the body fights against a familiar pathogen that has been in the body before. Cell-mediated immunity- where the body reacts to abnormal pathogens or substances.

Order of defenses T-cells attach to the antigen exposed using its antibodies, and releases a chemical called cytokines, which retrieves other B-cells and T-cells. The inflammatory response occurs in which capillaries expand allowing lymphocytes to pass through from the bloodstream and get to the infected site The first line of the nonspecific defense is the skin, not allowing substances to enter the body. Lymphocytes ingest the pathogen, revealing its antigen on the phagocyte’s surface

Killer T-cells inject cytotoxins into the infected cells, killing them. in the end, suppressor T-cells come around and demolish all the killer T-cells so that they don’t kill too many cells or healthy cells. Helper T-cells activate Killer T-cells and B-cells Entering B-cells attach onto the antigen of the pathogen and , some, turn into plasma cells that make antibodies against that specific pathogen. Other B-cells continue to ingest the pathogens, displaying the antigen on a MHCII molecules, for phagocytes to come and eat them.

1.) Which of these about Eubacteria is false? a) live nearly everwhere b.) Surrounded by a cell wall c.) Cell walls lack peptidoglycan d.) Cell wall contains peptidoglycan 1/25/11

2.) Which of these is not a known shape of bacteria? a.) bacilli b.) cocci c.) triangular d.) spirilla 1/25/11

3.) Which of these get energy from light? a.) Chemoheterotrophs b.) Photoheterotrophs c.) Photoautotrophs d.) Chemoautotrophs 1/25/11

4.) What is the result of Binary fission? a.) cell splits into two cells b.) two cells join together c.) cells explode d.) cells form endospores 1/25/11

5.) What is the main function of decomposers? a.) to soak up nutrients b.) to destroy nutrients c.) to recycle nutrients 1/25/11

6.) What is the only way viruses can reproduce? a.) asexually b.) by infecting other cells c.) sexually 1/25/11

7.) What is not a particle of a virus? a.) nucleic acid b.) cell wall c.) proteins d.) lipids 1/25/11

8.) How do viruses infect a cell? a.) they can pass through easily w/out any problems b.) create a hole in the cell membrane c.) through cell specific receptors 1/25/11

9.) Which infection cycle involves possibly becoming dormant in the cell for a period of time? a.) lytic b.) lysogenic c.) lactic d.) lactose 1/25/11

10.) In the lysogenic cycle what does bacteriophage not do? a.) injects its DNA into the bacteria b.) its DNA inserts itself into the bacteria chromosome c.) it attaches to a receptor so the cell consumes it d.) its DNA forms a circle 1/25/11

11.) which is false about viruses? a.) they are not considered alive b.) they are considered parasites c.) they are considered alive d.) they survive off other cells 1/25/11

12.) viruses produce diseases by disrupting the body’s _____ a.) organs b.) structure c.) equilibrium d.) skin 1/25/11

13.) which is some place where foreign substances can not enter the body? a.) toe nails b.) cuts c.) mouth/nose d.) openings in the skin 1/25/11

14.) what response takes place after a foreign substance enters the body? a.) respiratory b.) immune c.) hormonal d.) equilibrium 1/25/11

15.) which is not a type of immunity? a.) cell mediated b.) humoral c.) response 1/25/11

16.) T-cells attach to a.) antigens b.) antibodies c.) antrogens 1/25/11

17.) what is the first line of non-specific defense? a.) T-cells b.) skin c.) blood d.) B-cells 1/25/11

18.) what ingest the pathogens? a.) T-cells b.) B-cells c.) antigens d.) lymphocytes 1/25/11

19.) T-cells inject what into the infected cells? a.) cytotoxins b.) toxic chemicals c.) antigens d.) antibodies 1/25/11

20.) what activates T-cells and B-cells? a.) killer t-cells b.) helper t-cells c.) b-cells d.) plasma cells 1/25/11

Answer key: 1. c 2. c 3. b 4. a 5. c 6. b 7. b 1/25/11

Answer key: 8. c 9. b 10. c 11. c 12. c 13. a 14. b 1/25/11

Answer key: 15. c 16. a 17. b 18. d 19. a 20. b 1/25/11