1. Virus, Bacteria, Protists, and Fungi Chapters 19-21

2. What a virus is… and isn ’ t. A virus is not a cell. A virus is not a cell. –No nucleus, cell membrane, ribosomes, mitochondria, chloroplasts, etc. A virus is very small. A virus is very small. –3000 poloviruses could be contained in the period at the end of this sentence. A virus is not complex. A virus is not complex. –Genes: Humans (100,000), Bacteria (1000), a Virus… just 5!

3. Viral Structure Nucleic Acid Nucleic Acid –DNA or RNA, but not both. Protein Coat (capsid) Protein Coat (capsid) –Protects the nucleic acid from its environment. Envelope Envelope –Only found in viruses that infect animals. –Spike-like projections that recognize animal cells and bind to the cell surface.

4. T4 Bacteriophage Tobacco Mosaic Virus Influenza Virus Head Tail sheath DNA Tail fiber RNA Capsid Surface proteins Membrane envelope RNA Capsid proteins Section 19-2

5. Viral Replication Viruses don ’ t reproduce, they replicate. Viruses don ’ t reproduce, they replicate. Viruses cannot replicate on their own. Viruses cannot replicate on their own. Host cells. Host cells. Lytic Cycle. Lytic Cycle. –When the virus enters the cell it immediately begins to replicate, rapidly killing the cell. Lysogenic Cycle. Lysogenic Cycle. –Viral DNA is inserted into the host cell ’ s DNA. This DNA, called a PROPHAGE, may be reproduced several times and eventually reactivates.

6. Lytic and Lysogenic Infections

7. Are viruses alive? Properties of Life: Properties of Life: –Highly organized. Yes or no? –Use energy. Yes or no? –Grow and develop. Yes or no? –Reproduce. Yes or no? –Respond and adapt. Yes or no? Most scientists would say… NO. Most scientists would say… NO.

8. Section 19-2 Figure 19-11 Viruses and Cells

9. What are vaccinations? The process of injecting a person with a harmless (weakened or dead) form of a virus to stimulate the immune system to produce cells and proteins that will destroy that type of virus. The process of injecting a person with a harmless (weakened or dead) form of a virus to stimulate the immune system to produce cells and proteins that will destroy that type of virus.

10. Bacterial Structure Figure 14.10 Figure 14.10 –Flagella –Cell Membrane –Ribosome –Pili –Chromosome –Cell Wall

11. Peptidoglycan Cell wall Cell membrane Ribosome Flagellum DNA Pili Section 19-1 The Structure of a Eubacterium

12. Survival/Reproduction Binary Fission: the process by which bacteria replicate chromosomes and the cell divides. Binary Fission: the process by which bacteria replicate chromosomes and the cell divides. Power of doubling (1 penny doubled 20 times) Power of doubling (1 penny doubled 20 times) 1048576 cents or $10,485.76 1048576 cents or $10,485.76 Average bacteria doubles every 15-20 minutes Average bacteria doubles every 15-20 minutes Endospores Endospores –Thick-walled reproductive structures that can resist heat, drought, and radiation, sometimes living centuries before breaking open.

13. Classifying Bacteria Archaebacteria ( “ ancient ” ) Archaebacteria ( “ ancient ” ) –Methanogens: produce methane. –Thermophiles: heated conditions –Halophiles: salty conditions Eubacteria Eubacteria –“ True Bacteria ” – live in much less harsh environments than archebacteria. Many types and ways to classify.

14. Classifying Bacteria, cont. Shapes Shapes –Spheres (cocci), rods (bacilli), spirals (spirilla), chains (streptococci), clusters (staphylococci). Cell Wall Composition Cell Wall Composition –Gram-positive, Gram-negative. Nutrition (autotroph, heterotroph) Nutrition (autotroph, heterotroph) Respiration (aerobes, anaerobes) Respiration (aerobes, anaerobes)

15. The Roles of Bacteria Decomposers. Decomposers. –Breakdown dead material. –Convert (fix) nitrogen into usable forms for plants. Symbiosis. Symbiosis. –“ You scratch my back – I ’ ll scratch yours. ” Bacteria can be harmful. Bacteria can be harmful. –Slides of deadly bacteria.

16. Tooth decay Lyme disease Tetanus Tuberculosis Salmonella food poisoning Pneumonia Cholera Streptococcus mutans Borrelia burgdorferi Clostridium tetani Mycobacterium tuberculosis Salmonella enteritidis Streptococcus pneumoniae Vibrio cholerae Regular dental hygiene Protection from tick bites Current tetanus vaccination Vaccination Proper food-handling practices Maintaining good health Clean water supplies DiseasePathogenPrevention Section 19-3 Common Diseases Caused by Bacteria

17. Oncogenic viruses Retrovirus Adenoviruses Herpesviruses Poxviruses DNA RNA DNA Cancer Cancer, AIDS Respiratory infections Chickenpox Smallpox Type of VirusNucleic AcidDisease Section 19-3 Common Diseases Caused by Viruses

18. Protists Common characteristic: EUKARYOTES Common characteristic: EUKARYOTES Very diverse (20 new kingdoms?) Very diverse (20 new kingdoms?) Three general categories: Three general categories: –Animal-Like Protists (p. 355-357) –Plantlike Protists (p. 358-361) –Funguslike Protists (p. 362-364)

19. Section 20-1 Concept Map are classified by which include which Protists Animallike Funguslike Plantlike Parasites Take in food from the environment Produce food by photosynthesis Obtain food by external digestion Decomposers

20. Animallike Protists: Protozoans Animallike Protists: Protozoans A.Zooflagellates B.Sarcodines C.Ciliates 1.Internal Anatomy 2.Conjugation D.Sporozoans Section 20-2

21. Food vacuole Nucleus Contractile vacuole Pseudopods Section 20-2 Figure 20-4 An Amoeba

22. Anal pore Gullet Oral groove Trichocysts Lysosomes Food vacuoles Contractile vacuole Micronucleus Macronucleus Cilia Section 20-2 Figure 20-5 A Ciliate

23. Plantlike Protists: Unicellular Algae A.Chlorophyll and Accessory Pigments B.Euglenophytes C.Chrysophytes D.Diatoms E.Dinoflagellates Section 20-3 Section Outline

24. Gullet Chloroplast Nucleus EyespotFlagella Section 20-3 Euglena Carbohydrate storage bodies Pellicle Contractile vacuole

25. Plantlike Protists: Red, Brown, and Green Algae A.Red Algae B.Brown Algae C.Green Algae 1.Unicellular Green Algae 2.Colonial Green Algae 3.Multicellular Green Algae

26. Funguslike Protists A.Slime Molds 1.Cellular Slime Molds 2.Acellular Slime Molds B.Water Molds Section 20-5 Section Outline

27. MEIOSIS FERTILIZATION Zygote Germinating spore Spores Mature sporangium Young sporangium Mature plasmodium Feeding plasmodium Haploid (N) Diploid (2N) Section 20-5 Figure 20-23 The Life Cycle of an Slime Mold

28. Fungi 3 Common characteristics: 3 Common characteristics: –Cell wall are chitin. Same covering as insects. –Made of individual filaments, called hyphae. Tubes full of cytoplasm and nuclei. –Masses of hyphae combine to form the mycelium. This is the body of the fungus.

30. Hyphae Without Cross Walls Nuclei Cell wall Nuclei Cytoplasm Cross wall Cell wall Cytoplasm Hyphae With Cross Walls Section 21-1 Hyphae Structure

31. FERTILIZATION MEIOSIS HYPHAE FUSE Fruiting body (N + N) Button Secondary mycelium (N + N) Primary mycelium (N) + Mating type (N) - Mating type (N) Basidiospores (N) Zygote (2N) Basidia (N + N) Gills lined with basidia Gills Stalk Base Cap Haploid Diploid Section 21-2 The Life Cycle of a Basidiomycete

33. How does a fungus eat? Heterotrophs Heterotrophs Diffusion: most fungi absorb small organic nutrients from their environment. Diffusion: most fungi absorb small organic nutrients from their environment. Saprophytic: they absorb nutrients from dead or decaying organic matter. Saprophytic: they absorb nutrients from dead or decaying organic matter.