1. Three Domain System Carl R. Woese Based on Ribosomes Ribosomes are in all cells but they are not all alike. Three Domains: 1.Eukaryotes 2.Bacteria- Prokaryotes (pathogenic bacteria and bacteria that live in soil and water) 3.Archaea- Prokaryotes (bacteria without peptidoglycan; methanogens, halophiles, and hyperthermophiles)

2. Figure 10.1 The Three-Domain System. Bacteria Mitochondria Cyanobacteria Chloroplasts Thermotoga Gram-positive bacteria Proteobacteria Horizontal gene transfer occurred within the community of early cells. Nucleoplasm grows larger Mitochondrion degenerates Giardia Euglenozoa Diatoms Dinoflagellates Ciliates Animals Fungi Amebae Slime molds Plants Green algae Eukarya Extreme halophiles Methanogens Hyperthermophiles Origin of chloroplasts Origin of mitochondria Archaea

3. Taxonomic Hierarchy Domain Kingdom Phylum Class Order Family Genus Species

4. Fungi Figure 10.5 The taxonomic hierarchy. Eukarya Ascomycota Hemiascomycetes Saccharomycetales Saccharomycetaceae Saccharomyces S. cerevisiae Baker’s yeast Species Genus Family Order Class Phylum Kingdom Domain All organisms M. okinawensis Methanothermococcus Methanococcaceae Methanococcales Methanococci Euryarcheota None assigned for archaea Archaea Methanococcus E. coli Escherichia Enterobacteriaceae Enterobacteriales Gammaproteobacteria Proteobacteria None assigned for bacteria Bacteria

6. FUNGI

7. Fungi KingdomFungi Nutritional TypeChemoheterotroph MulticellularityAll, except yeasts Cellular Arrangement Unicellular, filamentous, fleshy Food Acquisition MethodAbsorptive Characteristic FeaturesSexual and asexual spores Mycology: the study of fungi

8. Table 12.1 Selected Features of Fungi and Bacteria Compared.

9. Vegetative Growth Molds ◦ The fungal thallus consists of hyphae; a mass of hyphae is a mycelium Unicellular fungi ◦ Fission yeasts divide symmetrically ◦ Budding yeasts divide asymmetrically Dimorphism ◦ Pathogenic dimorphic fungi are yeastlike at 37°C and moldlike at 25°C

10. Figure 12.2 Characteristics of fungal hyphae. Septum Cell wall Pore Nuclei Septate hypha Coenocytic hyphaGrowth of a hypha from a spore Spore

11. Figure 12.3a Aerial and vegetative hyphae. Aerial hyphae Aspergillus niger

12. Figure 12.4 A budding yeast. Parent cell Bud Bud scar

13. Figure 12.5 Fungal dimorphism. Yeastlike growth Moldlike growth

14. Life Cycle Spores- reproductive fungal product ◦ Asexual- formed by one organism; genetically identical to parent ◦ Sexual- formed by the fusion of 2 nuclei from 2 organisms; genetic characteristics of both parents ◦ Most are asexual.

15. ASEXUAL SPORES ConidiosporeSporangiospore Unicellular or multicellular Spores are not enclosed in a sac. Spores are released one at a time. Has a sporangium(sac) that encloses the spores. More than one spore is released at one time.

16. Figure 12.6a Representative asexual spores. Conidia Conidiophore

17. Figure 12.6e Representative asexual spores. Sporangiospores Sporangiophore

18. Sexual Spores Zygospore: fusion of haploid cells produces one zygospore Ascospore: formed in a sac (ascus) Basidiospore: formed externally on a pedestal (basidium)

19. Nutritional Adaptations pH-5 Aerobes(molds) and facultative anaerobes(yeast) Can grow in high salt and sugar environment and low moisture environments. Grow on a WIDE variety of substances.

20. Fungal Diseases (Mycoses) Systemic mycoses: deep within body Subcutaneous mycoses: beneath the skin Cutaneous mycoses: affect hair, skin, and nails Superficial mycoses: localized, e.g., hair shafts Opportunistic mycoses: caused by normal microbiota or environmental fungi

21. MEDICALLY IMPORTANT FUNGI

22. Aspergillus sp. Opportunistic Found in decaying vegetation Usually affects immunocompromised or people with other lung infections Causes pulmonary aspergilliosis; cough, wheezing, fever

23. Microsporum Cutaneous/Superficial Ringworm Circular patches are affected Transmitted with fomite contact

24. Stachybotrys Opportunistic Found in water damaged walls of buildings Can lead to pulmonary problems

25. Candida albicans Subcutaneous Normal flora of the genitourinary tract and mouth Dimorphic Overgrows when other normal flora is suppressed by antibiotics. Thrush and vaginitis(yeast infection)

26. Figure 21.17 Candidiasis. Candida albicansOral candidiasis, or thrush Blastoconidia Pseudohyphae Chlamydoconidia

27. Pneumocystis jirovecii Systemic Causes pneumonia in people who are immunocompromised especially AIDS and cancer patients.

28. Figure 24.20 The life cycle of Pneumocystis jirovecii, the cause of Pneumocystis pneumonia. Trophozoite, note extensions for feeding on tissue. Cyst Mature cyst Intracystic bodies Each trophozoite develops into a mature cyst. The mature cyst contains 8 intra- cystic bodies. The cyst ruptures, releasing the bodies. Trophozoite The bodies develop into trophozoites. The trophozoites divide.

29. Economic Effects of Fungi Saccharomyces cerevisiae: bread, wine, HBV vaccine Can control pests.

30. ALGAE

31. Algae KingdomProtista Nutritional TypePhotoautotroph MulticellularitySome Cellular Arrangement Unicellular, colonial, filamentous, tissues Food Acquisition MethodDiffusion Characteristic FeaturesPigments

32. Figure 12.12a Algae and their habitats. Red Orange Yellow Violet Blue Red algae Multicellular green algae Brown algae Unicellular green algae, diatoms, dinoflagellates Sublittoral zone Littoral zone Green algae, cyanobacteria, euglenoids LANDSURFACE Algal habitats

33. Life Cycle Sexual and Asexual- fragments can become a new algae

34. Rhodophyta Red algae Cellulose cell walls Most are multicellular Store glucose polymer Harvested for agar(media plates)

35. Dinoflagellates- Plankton Cellulose in plasma membrane Unicellular Store starch Neurotoxins cause paralytic shellfish poisoning

36. Protozoans

37. Protozoa KingdomVarious Nutritional TypeChemoheterotroph MulticellularityNone Cellular ArrangementUnicellular Food Acquisition MethodAbsorptive; ingestive Characteristic FeaturesMotility; some form cysts

38. Characteristics of Protozoa Two Morphological forms: ◦ Trophozoites- vegetative form; oval to irregular shape ◦ Cysts-some produce; resistant form; round shape

39. Characteristics of Protozoa Means of Motility ◦ Flagella ◦ Cilia ◦ Pseudopods

40. Giardia lamblia No mitochondria Multiple flagella Adheres to the intestinal wall. Causes diarrhea

41. Insert Fig 25.17 Figure 25.17 The trophozoite form of Giardia lamblia, the flagellated protozoan that causes giardiasis. Mark left by ventral sucker

42. Trichomonas vaginalis No mitochondria Multiple flagella No cyst Vagina and male urinary tract STD- greenish yellow discharge

43. Trypansoma brucei Hemoflagellate- lives in the bloodstream Tsetse fly African Sleeping Sickness- causes headache and fever that progress to coma

44. Plasmodium sp. Nonmotile Intracellular parasites Complex life cycles Female Anopheles mosquito Blood and liver are affected Merozoites-infect RBCs, reproduce and the RBC ruptures 48 hours later Chills, fever, headache and vomiting. Alternating periods. Estimated 200-400 million people are in infected

45. Figure 23.26 Malaria. Merozoites being released from lysed RBCs RBCs Merozoites RBCs Ring forms Malarial blood smear; note the ring forms.

46. Entamoeba histolytica Pseudopods Causes cell lysis of the intestinal tissue which leads to bloody and mucoid diarrhea. Transmitted through feces.

47. Insert Fig 25.19 Figure 25.19 Section of intestinal wall showing a typical flask-shaped ulcer caused by Entamoeba histolytica. Normal mucosa Ulcer

48. Toxoplasmosis gondii Nonmotile Carried in a cat’s gut Transmission: ◦ Ingesting undercooked meat ◦ Contact with cat feces People with healthy immune systems may have mild cold-like symptoms or none at all Congenital infection ◦ Stillbirth ◦ Neurological damage

49. Figure 23.24 The life cycle of Toxoplasma gondii, the cause of toxoplasmosis. If a pregnant woman accidentally ingests oocysts (contacted when changing a cat litter box), prenatal infection of the fetus may occur. If humans eat undercooked meat containing tissue cysts, they may become infected. Definitive host Tachyzoites Bradyzoites in tissue cyst Sporocysts Sporozoite Intermediate hosts Mature oocyst (10–13 μm x 9–11 μm) Sporogony Immature cyst Immature oocyst is shed in cat feces. Mature oocysts develop by sporogony and contain two sporocysts, each with four infective sporozoites. Oocysts can infect many hosts, including mice, domestic animals, and humans, via ingestion. Sporozoites from ingested oocysts invade animal tissue and develop into bradyzoites within tissue cysts or into tissue-invading tachyzoites. Cat ingests bradyzoites in tissue cysts of animals, usually mice. 2 3 4 5 1

50. Balatidium coli Cilia Trophozoites secrete proteases that destroy cells of the large intestine. Causes severe dysentery. Transmitted through fecal contamination of water

51. Helminths

52. Helminths KingdomAnimalia Nutritional TypeChemoheterotroph MulticellularityAll Cellular ArrangementTissues and organs Food Acquisition MethodIngestive; absorptive Characteristic FeaturesElaborate life cycles

53. Helminths (Parasitic Worms) Kingdom: Animalia ◦ Phylum: Platyhelminthes (flatworms)  Class: trematodes (flukes)  Class: cestodes (tapeworms) ◦ Phylum: Nematoda (roundworms)

54. Characteristics of Helminths Reduced digestive system Reduced nervous system Reduced locomotion Complex reproduction

55. Life Cycle of Helminths Monoecious (hermaphroditic) ◦ Male and female reproductive systems in one animal Dioecious ◦ Separate male and female Egg  larva(e)  adult

56. Question Why are the drugs used to treat parasitic helminths often toxic to the host? 12-14

57. Platyhelminths- Trematodes Also called flukes Absorb food through a cuticle

58. Schistosoma mansoni Tissue damage (granulomas) in response to eggs lodging in tissues African, Middle East, South America, Caribbean 2 nd only to malaria in the # of people it kills or disables Granuloma

59. (b) Life cycle of Schistosoma, cause of schistosomiasis. Figure 23.28 Schistosomiasis. Free-swimming cercariae penetrate human skin, losing tail. Intermediate host Cercariae are released from the snail. Cercariae travel through circulatory system to intestinal blood vessels, where they mature into adults. Adult female flukes lay eggs. (a) Male and female schistosomes. The female lives in a groove on the ventral (lower) surface of the male schistosome (“split-body”), is continuously fertilized, and continuously lays eggs. The sucker is used by the male to attach to the host. Eggs reach body of water after being excreted in human feces or urine. Cercaria (0.33 mm) Cercaria (0.13 mm) Definitive host Female (size: 15–20 mm) Eggs Male Adult flukes Egg (0.15 mm) Miracidium (0.2 mm) Male Mouth Sucker Female Mouth Eggs hatch into free-swimming larvae (miracidia). Miracidium reproduces in snail, forming several cercariae. Miracidium penetrates snail. 1 2 3 4 5 6 7 8

60. Platyhelminths- Cestodes Also called a tapeworm Scolex- head with suckers or hooks Absorb foods through cuticle Proglottids- segments; contains both female and male reproductive parts

61. Taenia saginata Found in cattle (beef tapeworm) Human ingest the proglottids found in the meat Abdominal distress

62. Nematoda Roundworms Complete digestive system Male and female Some are free living in soil Most common helminth infection

63. Nector americanus Hookworm Attaches and feeds on blood and tissue Leads to anemia and lethargic behavior

64. Ascaris lumbricodes Common in the SE US Absorb partially ingested food Can cause lung problems or blockages in the intestines, liver or pancreas Can come out of the anus, mouth, nose or navel

65. Enterobius vermicularis Most common in the US Females lay their eggs around the anus and this causes itching. Eggs get transmitted by hands and close contact Scotch-Tape test diagnosis

66. Adult pinworm Figure 12.29 The pinworm Enterobius vermicularis. Mouth Intestine Ovary Genital pore Anus Female (8–13 mm long) Mouth Intestine Genital pore Anus Spicules Male (2–5 mm long) Larva Egg (55 μ m long) Pinworm egg Testis

67. Arthropods as Vectors May transmit diseases (vectors) Kingdom: Animalia ◦ Phylum: Arthropoda (exoskeleton, jointed legs)  Lice, fleas, mosquitoes  Mites and ticks

68. Arthropods as Vectors Mechanical transmission Biological transmission ◦ Microbe multiplies in vector Definitive host ◦ Microbe’s sexual reproduction takes place in vector

69. Figure 12.31 Mosquito.

70. Figure 12.32 Tick.

71. Insert Fig 12.33 Figure 12.33 Arthropod vectors. 2.5 mm Rat flea Human louseDeer flyKissing bug 1 cm 2 cm