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Microbiology Chapter 5. Eukaryotes: Review the Compare/Contrast Prokaryotes and Eukaryotes from Chapter 4 Cells are larger 50 – 100 microns (prok. 5 microns) Membrane bound organelles Appendages : Flagella; Cilia Different: made of protein microtubules (9+2) Cell wall is chemically simpler
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Microbiology Chapter 5 Eukaryotes: Review the Compare/Contrast Prokaryotes and Eukaryotes from Chapter 4 Cells are larger 50 – 100 microns (prok. 5 microns) Membrane bound organelles Appendages : Flagella; Cilia Different: made of protein microtubules (9+2) Cell wall is chemically simpler Plasma membrane similar, some can use phagocytosis, or pinocytosis Cytosol aka. Cytoplasm fluid matrix, cytoskeleton of protein tubes and fibers to anchor structures, provide shape, and transport material within cell
Microbiology Chapter 5 Eukaryotes: Organelles, membrane bound, specialization of function.
Microbiology Chapter 5 Eukaryotes: Organelles, membrane bound, specialization of function. Nucleus: dbl memb. Contains almost all cell DNA; chromosome. Nucleolus (nucleus within the nucleus) Site of RNA synthesis and ribosome production.
Microbiology Chapter 5 Eukaryotes: Organelles, membrane bound, specialization of function. Endoplasmic Reticulum (ER) network of flattened mebranes Rough ER studded with ribosomes, protein synthesis Smooth ER – no ribosomes, lipid synthesis
Microbiology Chapter 5 Eukaryotes: Organelles, membrane bound, specialization of function. Golgi Complex: membranes and sacs where proteins are modified, repackaged and shipped (like UPS or FED EX)
Microbiology Chapter 5 Eukaryotes: Organelles, membrane bound, specialization of function. Lysosomes: Vesicles containing lytic enzymes (suicide sac)
Microbiology Chapter 5 Vacuoles: membrane bound areas of storage; sugars, starch, fat, even water. Especially in plants.
Microbiology Chapter 5 Eukaryotes: Organelles, membrane bound, specialization of function. Mitochondria: Cell power plant, most ATP made here. Site of Krebs cycle and electron transport Double membrane bound, inner membrane folded to increase surface area (cristae). Imbedded are the cytochromes etc. Inner fluid filled matrix contains enzymes for Krebs
Microbiology Chapter 5 Eukaryotes: Organelles, membrane bound, specialization of function. Plant Chloroplast: site of photsynthesis, Carbon Dioxide and water plus sunlight are made into glucose
Microbiology Chapter 5 Eukaryotes: Organelles, membrane bound, specialization of function. Centromere (Centriole, Centosome) organelle made of microtubules, generates spindle needed for Mitosis
Microbiology Chapter 5 Eukaryotes: Survey of Eukaryote Microbes we study in this class Fungi Protozoans Helminths Remember the overlap of Arthropod vectors Parasitology
Microbiology Chapter 5 Fungi: Mycology; Fungi make up there own Kingdom; a very diverse group of organisms found in almost any environment. They are prominent “decomposers” of dead and decaying matter. Saprophyte is a term used to describe their role in nature – live on dead material. They secrete exoenzymes and absorb nutrients. Morphology: Single celled – yeasts, used in baking and brewing, some cause disease Multicellular – Molds and mushrooms, filamentous decomposers and some cause animal and plant disease
Microbiology Chapter 5 Yeasts: 1. Oval shaped 2. Reproduce asexually by budding When growing on agar medium, appear pasty and form large colonies. Special agar buffered to an acidic pH
Microbiology Chapter 5 Molds : Filamentous (fuzzy) fungi. Cells are tube like and connected into long filaments. The filaments are called hyphae or mycelium (hypha; mycelia plural). They can branch off, form rhizoid root-like cells, aerial mycelium with spore containing structures. Some filaments have cross walls separating individual cells and others appear as a multinucleate mass.
Microbiology Chapter 5 Molds: Aerial mycelium of Penicillium, conidiophore (like arm, fingers) conidiospores (asexual spores)
Microbiology Chapter 5 Molds: Rhizopus, bread mold, aseptate, note “rhizoid”, stalk (sporangiophore) and sporangium (black colored sac) filled with black spores (sporangiospores – asexual)
Microbiology Chapter 5 Molds: Some are “dimorphic” = two forms: grow in nature as molds but in our bodies grow as yeasts. Some nasty pathogens are dimorphic Mushrooms and Bracket “shelf” fungi are common decomposers in nature.
Microbiology Chapter 5 Basic characteristics of Fungi Saprophytes, heterotrophic, cell walls of chitin, a few are parasitic (ringworms) and a few cause serious human disease. Distribution: ubiquitous (anywhere), any environment, temp. food source, etc. They seem to prefer slightly cooler and more acidic environments than bacteria. We use Sabouraud dextrose agar in the lab. Economic importance: greatest negative impact is plant disease and crop loss (Irish potato famine). Rusts, smuts, powdery mildew. Medical importance: Many human pathogens. We are pretty resistant to fungal infections. Some are opportunists: Candida and dermatophytes (ringworms). We will study 4 or 5 nasty respiratory fungal infections later.
Microbiology Chapter 5 Taxonomy of Fungi: A royal pain in the ______. Medical mycology demands it. We must prevail. Know the 4 classes, based on presence of a “sexual” spore. Know the examples given. Class – Zygomycetes; Forms a sexual spore called a “zygospore”, asexual spores in a sporangium “sporangiospores”. Ex. Rhizopus Asexual sexual
Microbiology Chapter 5 Ascomycetes: Sexual spores in an ascus (sac); representative organism is Penicillium; asexual conidiospores, sexual ascospores Asexual – conidiospores 2. Sexual - ascospores
Microbiology Chapter 5 Basidiomycetes: mushrooms, sexual spore at the end of a club like “basidium” Deuteromycetes; catch all class, no sexual mechanism noted. Many human pathogens are found here. Candida would be a godd example. Candida – yeast Candida pseudomycelium (weird)
Microbiology Chapter 5 Protozoans: Kingdom Protista. Formerly thought of as “animals” since they generally have no cell walls. Most are free living in watery environments and have developed special structure to expel excess water taken on in a fresh water environmment. They also have a variety of mechanisms for obtaining food. Many exhibit two distinct “life” forms: A Trophozooite (troph); an active feeding form. A Cyst, a non active “survival form”. Many are parasites spread by the fecal-oral route. Most acquire infections by ingesting the encysted form in contaminated food or water.
Microbiology Chapter 5 Classes of Protozoans – based on “Motility” 1. Flagellates (Mastigophora): Motile by flagella. Examples: free living Euglena and parasites Giardia and Typanosoma
Microbiology Chapter 5 Trypanosoma – sleeping sickness, transmitted via TSETSE fly
Microbiology Chapter 5 Sarcodinans – Amebas motile by pseudopods, many are free living, some are parasites and cause disease (usuallyfecal-oral ) Ameba proteus Entameba histolytica
Microbiology Chapter 5 A quick word about life cycles of protozoans: troph - cyst
Microbiology Chapter 5 3. Ciliates: motile by “cilia”. Free living Paramecium and Intestinal pathogen – Balanditium coli (troph)
Microbiology Chapter 5 Balanditium coli (cyst)
Microbiology Chapter 5 4. Sporozoans (Apocomplexa) Not motile. Very complex life cycles often with a vector. Plasmodium species causing malaria with a mosquito vector. Toxoplasma parasite from cat litter box.
Microbiology Chapter 5 Multicellular Parasites: Helminths; the worms. These diseases are often diagnosed with microscopic examination of stool samples for characteristic eggs. Classified based on body form of adult worm (round or flat) Platyhelminthes: Flat worms Nematodes: round worms Platyhelminthes: Two divisions Cestodes: tape worms; often long and segmented Trematodes: “flukes” leaf like body forms
Microbiology Chapter 5 Cestodes: tape worms; often long and segmented Holdfast structure attached to intestine = Scolex Segments: proglottids, as they mature produce fertile eggs Either segments or eggs pass in the stool and contaminated water or food Taenia saginata – beef tapeworm Taenia solium – pork tapeworm Diplydium canium – dog tapeworm (complex life cycle) Can be prevented, meat inspection, treat water, cook food, good hygiene
Microbiology Chapter 5 Taenia saginata – beef tapeworm
Microbiology Chapter 5 Taenia solium – pork tapeworm; cook the sausage to 165
Microbiology Chapter 5 Diplydium canium : don’t let fido lick your face
Microbiology Chapter 5 Trematodes: “flukes” leaf like body forms, non segmented, complex life cycles, many intermediate hosts (snails, fish), even free swimming larvae in contaminated water Schistosoma mansoni
Microbiology Chapter 5 Nematodes: round worms, very diverse group, from tiny, thread-like, to giant pork roundworm (Ascaris) Pinworms (a family affair) Enterobrius vermicularis (itchy butt, followed by scotch tape test)
Microbiology Chapter 5 Nematodes: round worms Hookworm: Necator americanus, larva in warm moist soil, wear shoes
Microbiology Chapter 5 Nematodes: round worms Ascaris lumbricoides, giant pork roundworm (adults 12 inches long), can block intestine, Ascaris types are common in pets (puppies need worming)
Microbiology Chapter 5 Nematodes: round worms Trichinella spiralis: cook pork, bear, and horse meat
Microbiology Chapter 5 Nematodes: round worms; and so many more, filarial worms, heart worms filarial worms
Microbiology Chapter 5 Anasakis worm in fish: Sushi? Anyone?
Microbiology Chapter 5 Arthropod vectors: animals with “jointed” feet, bite and transmit microbes Fleas: plague, rabbit fever Mosquito: malaria Body louse : typhus Flies: sleeping sickness Kissing bug (Reduvids): American sleeping sickness Ticks: arachnids; lyme disease, spotted fevers See pg. 619 text