Microbio - Lab Exam 2 (Labs 31-34) PDF

Chapter 31 1. Recognize the terminology and structures unique to fungi, matching them to their correct definition. - Systemic: infection that spreads throughout the body - Saprophytic: organism that feeds on decaying organic matter - Septate hyphae: hyphae that have cross walls -...

Chapter 31 1. Recognize the terminology and structures unique to fungi, matching them to their correct definition. - Systemic: infection that spreads throughout the body - Saprophytic: organism that feeds on decaying organic matter - Septate hyphae: hyphae that have cross walls - Mycelium: main body of the fungus - Coenocytic: hyphae that are multinucleate - Pseudohyphae: chains of yeast cells that don’t separate - Sporangiospores: asexual spores produced inside of a sac - Dimorphic fungus: mold form or yeast form depending on environment 2. Contrast fungi with other eukaryotes and with bacteria regarding their role in the environment, characteristics, and reproduction. - Applies to bacteria only: prokaryotic, cell wall composed of peptidoglycan, all members unicellular - Applies to fungi only: eukaryotic, cell wall composed of chitin, members multicellular or unicellular, can be decomposers - Applies to both bacteria and fungi: can reproduce asexually, can be pathogenic, some members produce antibiotics 3. Identify common fungal specimens when observing prepared slides, using the best magnification for each specimen. - Look in lab book pages 322-324 4. Associate medically important fungi with the disease(s) they cause or pharmaceutical products they produce. - Diseases: - Candida: cutaneous, oral, and vulvovaginal candidiasis - Rhizopus: opportunistic mucormycosis - Penicillium: opportunistic infections (rare) - Trichophyton: Dermatophytosis (ringworm, athlete’s foot, nail infections) - Pharmaceutical products: - Penicillium produces Penicillin 5. Identify the mechanism of action and applications of common antifungal medications. - Miconazole: used to treat dermatophyte infections, candidiasis, and topical fungal infections; can find over-the-counter  - Amphotericin B: Candida species, Aspergillus species, Cryptococcus neoformans, histoplasma capsulatum and Coccidioides immitis Chapter 32 1. Recognize the terminology and structures unique to arthropods, matching them to their correct definition. - Molting: periodic shedding and regrowth of an exoskeleton - Invertebrate: animals that lack a backbone - Vector: an organism that transmits disease from host-to-host - Chitin: found in cell walls of fungi and exoskeleton of arthropods - Ectoparasite: an organism that lives on the outside of its host, deriving nutrients at the host’s expense 2. Contrast arthropods with other eukaryotes and with bacteria regarding their role in the environment, characteristics, and reproduction. - Role in the environment: - Arthropods: pollinators, decomposers, predators, vectors of disease - Other Eukaryotes: plants are primary producers, fungi are decomposers - Bacteria: decomposers, pathogens, symbionts (nitrogen-fixing bacteria in plants) - Characteristics: - Arthropods: Segmented bodies, jointed appendages, exoskeletons made of chitin - Other eukaryotes: cell walls of plants, cell membranes of protists, hyphae of fungi - Bacteria: unicellular, prokaryotic organisms - Reproduction: - Arthropods: sexual reproduction, with male and females mating to produce offspring. Some arthropods can exhibit parthenogenesis- females producing offspring without mating - Other eukaryotes: sexual reproduction (plants, animals), and asexual reproduction (some protists), and spore formation (fungi) - Bacteria: asexually, through binary fission where a single bacterial cell divides into two identical daughter cells 3. Identify the clinical importance of arthropods. - Arthropods can serve as vectors, transmitting disease-causing pathogens from host-to-host - They can be ectoparasites (pathogen transmission during feeding) - They can cause diseases (scabies, pediculosis) by burrowing into skin 4. Contrast mechanical and biological vectors, and intermediate host and definitive host vectors. - Mechanical vectors: pathogen doesn’t replicate in vector, transported externally on surface of vector (ex. Transmission of Salmonella by house flies) - Biological vectors: pathogen reproduced in vector, infects host via saliva or defecation 5. Identify common arthropod specimens when observing prepared slides, using the best magnification for each specimen. - Look through lab book/lab report 6. Associate medically important vectors with the disease(s) they transmit. - Spiders, ticks, and mites: - Ixodes species (deer tick): lyme disease - Amblyomma americanum (Lone Star tick): Ehrlichiosis - Insects: - Pediculus species (human louse): Epidemic typhus - Xenopsylla: Bubonic plague - Anopheles (mosquito): malaria - Culex (mosquito): arthropod-borne viral encephalitis Chapter 33 1. Recognize the terminology and structures unique to protozoa, matching them to their correct definition. - Pseudopodia: lobe-like cytoplasmic extensions that some protozoa can use to move and feed - Mixotrophic: capable of both heterotrophy and autotrophy (photosynthesis) - Schizogony: form of asexual reproduction that produces multiple daughter cells at once - Cyst stage: dormant protective stage produced by many protozoa - Trophozoite stage: actively feeding and reproducing stage of protozoa - Mitosome: mitochondrial remnant seen in Giardia - Hydrogenosome: mitochondrial remnant seen in Trichomonas - Axostyle: supportive rod of microtubules seen in Trichomonas - Undulating membrane: wave-like membrane attached to a flagellum seen in Trichomonas and Trypanosoma  - Kinetoplast: darkly staining mass of mitochondrial DNA found in some protozoa 2. Contrast protozoa with other eukaryotes and with bacteria regarding their role in the environment, characteristics, and reproduction. - Protozoa act as predators, recyclers, and parasites - Single-celled, have a nucleus, and move around using flagella, cilia, and pseudopods - Can reproduce sexually (like animals and plants) but some also reproduce asexually (like fungi and algae) 3. Identify common protozoal specimens when observing prepared slides, using the best magnification for each specimen. - Look in lab book pages 343-347 4. Associate medically important protozoa with the disease(s) they cause, the infectious stage, and how they are transmitted to humans or other animals. - Entamoeba histolytica: Amebiasis (gastroenteritis) - Giardia intestinalis: Giardiasis - Leishmania species: Leishmaniasis - Cutaneous leishmaniasis: milder and produces skin or mucous membrane sores - Visceral leishmaniasis: more severe, affecting spleen, liver, and bone marrow - Plasmodium: Malaria - Trichomonas vaginalis: Trichomoniasis - Trypanosoma brucei or T. cruzi: - T. brucei causes African sleeping sickness - T. cruzi causes American trypanosomiasis or Chagas’ disease 5. Identify the mechanism of action and applications of common antiprotozoal medications. - Metronidazole: most common treatment for miscellaneous protozoal infections; believed to work by damaging DNA of protozoans that respire anaerobically - Aminoquinolines: treats Malaria; prevent replication of the parasite - Pentamidine: most common treatment for the first stage of trypanosomiasis; interferes with DNA, RNA, and protein synthesis Chapter 34 1. Recognize the terminology and structures unique to helminths, matching them to their correct definition. - Scolex: Anterior end of a tapeworm, with sucker and/or hooks for attachment to the host. - Proglottids: segments of the tapeworm body that contain reproductive organs; they mature as they move away from the scolex - Miracidium: ciliated larval stage of flukes that hatches from eggs and infects the first intermediate host (e.g., snails) - Cercariae: Larval form of flukes that emerge from the snail and can infect the next host. - Nematode: roundworm, long cylindrical parasitic worms that taper at each end. They have complete digestive tracts and an outer protective layer called a cuticle. - Dioecious: species where male and female reproductive organs are in separate individuals - Monoecious: species have male and female reproductive organs in a single individual 2. Contrast helminths with other eukaryotes and with bacteria regarding their role in the environment, characteristics, and reproduction. a. Role in environment: i. Helminths: parasitic, often harming hots, can influence host populations ii. Other Eukaryotes: can be parasitic, mutualistic, or free-living iii. Bacteria: Decomposers, pathogens, nitrogen fixers, crucial for nutrient cycling b. Characteristics: i. Helminths: multicellular, macroscopic, complex body systems; specialised structures for parasitism ii. Other Eukaryotes: can be unicellular or multicellular; includes plants, fungi, and animals iii. Bacteria: Unicellular, prokaryotic, no nucleus c. Reproduction: i. Helminths: Sexual (dioecious or monoecious) and asexual stages; complex life cycle ii. Other Eukaryotes: Sexual and asexual reproduction are common iii. Bacteria: Primarily binary fission (asexual); horizontal gene transfer is common 3. Identify common helminthic specimens when observing prepared slides, using the best magnification for each specimen. 4. Associate medically important helminths with the disease(s) they cause, the infectious stage, and how they are transmitted to humans or other animals. a. Liver fluke: Fasciola hepatica i. Disease: Fascioliasis ii. Infectious stage: Metacercariae iii. Transmission: ingestion of contaminated aquatic plants b. Blood fluke: Schistosoma i. Disease: Schistosomiasis ii. Infectious stage: Cercariae iii. Transmission: Skin penetration during freshwater exposure c. Tapeworm: Taenia saginata i. Disease: Taeniasis ii. Infectious stage: Cysticerci iii. Transmission: Consuming undercooked beef d. Tapeworm: Taenia solium i. Disease: Taeniasis, Cysticercosis ii. Infectious stage: Cysticerci iii. Transmission: consuming undercooked pork e. Nematode: Enterobius vermicularis (pinworms) i. Disease: Enterobiasis ii. Infectious stage: Eggs iii. Transmission: Fecal-oral route f. Nematode: Ancylostoma duodenale (hookworms) i. Disease: ancylostomiasis ii. Infectious stage: larvae iii. Transmission: burrowing through human skin g. Nematode: Ascaris lumbricoides (most common nematode infestation in humans) i. Disease: Ascariasis ii. Infectious stage: Eggs iii. Transmission: Ingestion of contaminated food/water 5. Identify the mechanism of action and applications of common anthelminthic medications. a. Praziquantel i. Mechanism of action: alters cell membrane permeability, including paralysis and death of the parasite ii. Applications: Effective against flukes and some tapeworms b. Albendazole i. Mechanism of action: inhibits microtubule formation, distrupting glucose uptake. Cuts off nutrients to parasite ii. Applications: Used for nematodes and some cestodes c. Mebendazole i. Mechanism of action: inhibits microtubule formation, distrupting glucose uptake. Cuts off nutrients to parasite ii. Applications: Used for pinworms and roundworms