Lecture Exam 1 Microbiology Blue Print PDF

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Great set of notes, taken with all the course material in mind. This should give you a strong foundation...

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Study Guide (Blueprint) for Micro Lecture Exam 1 [CHs. 1, 4 & 5] Chapter 1 - The Main Themes of Microbiology: Definition of microbiology; and the branches of microbiology and their specific descriptions. Microbiology: The study of organisms to small to be seen without magnification. Understand the term “ubiquitous” in reference to a characteristic of microorganisms Microorganisms are ubiquitous (which means being or seeming to be everywhere at the same time). Note the major groups or classes of microorganisms with specific examples. Bacteria Viruses Fungi Protozoa Algae Helminths (parasitic worms) Be able to describe the benefits of microorganisms in the flow of energy and nutrients (i.e. benefits of photosynthesis and decomposition). The flow of energy and food through the earth’s ecosystems • Photosynthesis: Light fueled conversion of carbon dioxide to organic material • Decomposition: Breakdown of dead matter and wastes into simple compounds (Caused by fungi) Be able to describe the commercial and industrial uses of microorganisms (i.e. Biotechnology, Bioremediation and Genetic engineering).  Biotechnology: Production of foods, drugs, and vaccines using living organisms  Genetic engineering: Manipulating the genes of organisms to make new products  Bioremediation: Using living organisms to remedy an environmental problem ● Define epidemiology, ecology, pathogens, parasites and saprophytes.  Parasites live on or in the body of another organism called the host and it damages the host.  Pathogens: Microbes that do harm  Epidemiology: the branch of medicine which deals with the incidence, distribution, and possible control of diseases and other factors relating to health.

 Ecology: the branch of biology that deals with the relations of organisms to one another and to their physical surroundings.  Saprophytes: a plant, fungus, or microorganism that lives on dead or decaying organic matter. Note the description and structural differences between Prokaryotes and Eukaryotes; and be able to compare them based on their relative sizes (e.g. from smallest to the largest).  Prokaryotes (pre-nucleus): Simple cells  Eukaryotes (true nucleus): Complex cells (Human Cells,Plant Cells &Fungi)  Viruses: Acellular, parasitic particles composed of a nucleic acid and protein (Need a host for survival) - Obligated ● Historical foundations of microbiology: know the major contributors such as  Antonie Van Leeuwenhoek – Developed the microscope  Edward Jenner - Use of Scientific Method in Disease Control: Introduction of Vaccination (Through the use of cow pox, Jenner developed the small pox vaccine)  Louis Pasteur – disproved spontaneous generation (an early belief that some forms of life could arise from vital forces present in nonliving or decomposing matter - flies from manure, etc.) & diproved the Theory of Biogenesis (the idea that living things can only arise from other living things)  Showed microbes caused fermentation and spoilage  Disproved spontaneous generation of microorganisms  Developed pasteurization  Demonstrated what is now known as Germ Theory of Disease  Robert Koch - Germ Theory of Disease (Many diseases are caused by the growth of microbes in the body and not by sins, bad character, or poverty, etc) 2 contributors Louis Pasteur and Robert Koch  Joseph Lister -introduced aseptic techniques to reduce microbes in medical settings and prevent wound infections  Discovery of Spores and Sterilization - John Tyndall and Ferdinand Cohn each demonstrated the presence of heat resistant forms of some microbes. Cohn determined these forms to be heat-resistant bacterial endospores.  Sterility requires the elimination of all life forms including endospores and viruses. ● Know the steps or stages in the establishment of Scientific Method; and be able to arrange them in the correct sequence; and describe each step. Know its application in disease control or vaccination.  a method of procedure that has characterized natural science since the 17th century, consisting in systematic observation,

measurement, and experiment, and the formulation, testing, and modification of hypotheses. ● Describe endospores and their importance in resistance to extreme conditions.  Discovery of Spores and Sterilization - John Tyndall and Ferdinand Cohn each demonstrated the presence of heat resistant forms of some microbes. Cohn determined these forms to be heat-resistant bacterial endospores.  Endospores - A differentiated cell formed within cells of certain Gram-positive bacteria that are extremely resistant to heat and other harmful conditions and agents. Endospore are the resting stage during the life cycle of some bacteria, formed in response to adverse conditions. Endospores are formed within a vegetative bacterial cell when the environmental conditions no longer support cell growth.  Sterility requires the elimination of all life forms including endospores and viruses. ● Define taxonomy; note the levels of classification; note the 3 main domains of life; the 6 kingdoms; and the method of assigning specific names to microorganisms.  Taxonomy: organizing, classifying, and naming living things; formal system originated by Carl von Linn/ (1701-1778) Levels of classification (Dear King Philip Came Over For Good Soup)  Domain – (Archaea, Bacteria, & Eukarya )  Kingdom:  Phylum or Division Three Domains of Life  Bacteria - true bacteria  Archaea - odd bacteria that live in extreme environments, high salt, heat, etc.  Eukarya - have a nucleus and organelles The 6 kingdoms

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Class Order Family Genus Species

Method of assigning specific names to microorganisms  Scientists use a two-name system called a Binomial Naming System. Scientists name animals and plants using the system that describes the genus and species of the organism. Chapter 4 - A Survey of Prokaryotic Cells and

Microorganisms: Know the characteristics common to all living organisms All living things (single and multicellular) are made of cells that share some common characteristics: • Basic shape – spherical, cubical, cylindrical • Internal content – cytoplasm, surrounded by a membrane • DNA chromosome(s), ribosomes, metabolic capabilities All living organisms share several key characteristics or functions: order, sensitivity or response to the environment, reproduction, growth and development, regulation, homeostasis, and energy processing. When viewed together, these characteristics serve to define life.

Two basic cell types: eukaryotic and prokaryotic Eukaryotic cells: animals, plants, fungi, and protists Compare and contrast Prokaryotic and Eukaryotic cells in terms of: Nucleus and membrane bound organelles DNA Molecule Cell Wall Glycocalyx ➢ ll (Plasma) Membrane Cytoplasm Eukaryotic cells: animals, plants, fungi, and protists • Contain membrane-bound organelles that compartmentalize the cytoplasm and perform specific functions • Contain double-membrane bound nucleus with DNA chromosomes Prokaryotic cells: bacteria and archaea • No nucleus or other membrane-bound organelles but contains ribosomes

Prokaryotic cell structure:  Structure external to the cell wall, their descriptions and functions

 Patterns of arrangement of Flagella (For matching questions)  Distinguish between Gram-positive (G+) and Gram-negative (G-) cell walls in terms of chemical composition and staining properties Two different groups of bacteria demonstrated by Gram stain:  Gram-positive bacteria: thick cell wall composed primarily of peptidoglycan and cell membrane  Gram-negative bacteria: outer cell membrane, thin peptidoglycan layer, and cell membrane

The Gram Stain  Differential stain that distinguishes cells with a gram-positive cell wall from those with a gram-negative cell wall  Gram-positive - retain crystal violet and stain purple

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 Gram-negative - lose crystal violet and stain red from safranin counterstain Important basis of bacterial classification and identification Practical aid in diagnosing infection and guiding drug treatment

Review the medical importance of endospores • Have a 2-phase life cycle: • Vegetative cell – metabolically active and growing • Endospore – When exposed to adverse environmental conditions; capable of high resistance and very long-term survival. It allows the bacterium to produce a dormant and highly resistant cell to preserve the cell's genetic material in times of extreme stress. Endospores can survive environmental assaults that would normally kill the bacterium. prokaryotic morphology: note the 3 basic shapes of bacterial cells (cocci, bacilli, and spiral shapes) with bArrangements of bacterial cells (Diplococci, Clusters, Chains, or Sarcina)

Structure of the cell wall, it’s chemical composition and functions

Note the structures internal to the cell wall their descriptions and functions Prokaryotes have a cell membrane or plasma membrane that acts like a protective cover. They also have a rigid cell wall for added support and protection. Prokaryotic cells have ribosomes, which are molecules that make proteins. Their genetic material is in the nucleoid, which is the region where DNA lives. Prokaryotes are unicellular organisms that lack organelles or other internal membrane-bound structures. Therefore, they do not have a nucleus, but, instead, generally have a single chromosome: a piece of circular, double-stranded DNA located in an area of the cell called the nucleoid. Chapter 5 - A Survey of Eukaryotic Cells and Microorganisms: ● Eukaryotic cell structure: Note the 3 main parts of the Eukaryotic cell ➢ Structure external to the cell wall or cell membrane, their descriptions and functions. External Structures: Locomotor Appendages Flagella • Long, sheathed cylinder containing microtubules in a 9+2 arrangement

• Covered by an extension of the cell membrane • 10× thicker than prokaryotic flagella Cilia • Similar in overall structure to flagella, but shorter and more numerous • Found only on a single group of protozoa and certain animal cells • Function in motility, feeding, and filtering External Structures: Glycocalyx An outermost boundary that comes into direct contact with environment Usually composed of polysaccharides Appears as a network of fibers, a slime layer or a capsule Functions in adherence, protection, and signal reception Beneath the glycocalyx • Fungi and most algae have a thick, rigid cell wall • Protozoa, a few algae, and all animal cells lack a cell wall and have only a membrane Structure of the cell wall and cell membrane, it’s physical and chemical composition and functions. Boundary of the Cell: Cell Wall Rigid, provides structural support and shape Fungi have thick inner layer of polysaccharide fibers composed of chitin or cellulose and a thin layer of mixed glycans Boundary of the Cell: Cell/Cytoplasmic Membrane Typical bilayer of phospholipids and proteins (Allows lipids to enter the cell due to their lipid structure) Sterols confer stability Serves as selectively permeable barrier in transport Eukaryotic cells also contain membrane-bound organelles that account for 60-80% of their volume Nucleus Compact sphere, most prominent organelle of eukaryotic cell Nuclear envelope composed of two parallel membranes separated by a narrow space and is perforated with pores Contains chromosomes Nucleolus – dark area for rRNA synthesis and ribosome assembly

Function of Internal Structures within the Eukaryotic Cell

Nuclear changes during Mitosis (Eukaryotic Cells) 1. Interphase: Resting state riot to cell divisions 2. Prophase: Organelles become more prominent 3. Metaphase: The alignment of the chromosome 4. Anaphase: Chromosome begin to pull part to opposite poles of the cell (chromosome Splits) 5. Telophase: Cell begins to cleave as the chromosome are now at opposite ends. Know the major internal structures; their specific descriptions and functions [e.g. RER, SER, Lysosomes, Mitochondria, Golgi apparatus, cytoskeleton (microtubules and microfilaments), and chloroplasts] Internal Structures: Endoplasmic Reticulum • Rough endoplasmic reticulum (RER) – originates from the outer membrane of the nuclear envelope and extends in a continuous network through cytoplasm; rough due to ribosomes; proteins synthesized and shunted into the ER for packaging and transport; first step in secretory pathway • Smooth endoplasmic reticulum (SER) – closed tubular network without ribosomes; functions in nutrient processing, synthesis, and storage of lipids

Internal Structures: Golgi Apparatus • Modifies, stores, and packages proteins • Consists of a stack of flattened sacs called cisterna

Fungi: Structural types and their descriptions, reproductive cycles (asexual and sexual spore formations), and role or importance of fungi. Kingdom Fungi Majority are unicellular or colonial; a few have cellular specialization Hyphae – long filamentous fungi or molds Yeast – round ovoid shape, asexual reproduction (some exist in either form – dimorphic – characteristic of some pathogenic molds) Microscopic Fungi: Hyphae Filamentous fungi (molds) –cottony, hairy, or velvety texture Woven intertwining mass of hyphae called mycelium; may be divided by cross walls (septa) Vegetative hyphae – digest and absorb nutrients (Rapidly grows) Reproductive hyphae – produce spores for reproduction (Asexual) Fungal Reproduction Primarily through spores formed on reproductive hyphae Asexual Spore Formation Yeast & Mold Sporangiospores: formed by successive cleavages within a saclike head called a sporangium = contains the spores initially enclosed but released when the sporangium ruptures. Conidiospores (conidia): free spores not enclosed by a spore-bearing sac.

Sexual Spore Formation Spores are formed following fusion of two different strains and formation of sexual structure Sexual spores and spore-forming structures are one basis for classification

Formation of Zygospores

Production of Ascospores

Formation of Basidiospores

Microscopic Fungi: Yeasts • Cell distinguished by its round to oval shape and by its mode of asexual reproduction • Some form a pseudohypha, a chain of yeasts formed when buds remain attached in a row Fungal Identification Isolation on specific media Macroscopic and microscopic observation of: • Asexual spore-forming structures and spores • Hyphal type (long filamentous fungi or molds) • Colony texture and pigmentation • Physiological characteristics • Genetic makeup Roles of Fungi Fungi involvement in medicine (pathogenesis), nature, and industry can be at two levels: • Adverse impact • Mycoses, allergies, toxin production Beneficial impact: • Sources of antibiotics, alcohol, organic acids, vitamins • Decomposers of dead plants and animals • Used in making foods and in genetic studies Protists: Types and descriptions. Characteristics, life-cycle (stages), and importance of protozoa.

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Algae - eukaryotic organisms, usually unicellular and colonial, that photosynthesize with chlorophylla Algae Photosynthetic organisms Microscopic forms are unicellular, colonial, filamentous Macroscopic forms are colonial and multicellular Contain chloroplasts with chlorophyll and other pigments Cell wall May or may not have flagella Most are free-living in fresh and marine water – plankton, provide basis of food web in most aquatic habitats Produce large proportion of atmospheric O2

Protozoa (water bodies)- unicellular eukaryotes that lack tissues and share similarities in cell structure, nutrition, life cycle, and biochemistry  Vary in shape, lack a cell wall  Most are unicellular; colonies are rare  Most are harmless, free–living in a moist habitat  Some are animal parasites and can be spread by insect vectors  All are heterotrophic–lack chloroplasts  Feed by engulfing other microbes and organic matter  Most have locomotor structures–flagella, cilia,  or pseudopods  Exist as trophozoite (active form)–motile feeding stage  Many enter a dormant stage during unfavorable conditions for growth and feeding–cyst (inactive form used to survive harsh condition)  All reproduce asexually, mitosis or multiple fission; many also reproduce sexually– conjugation (Pili- connecting) Protozoan Identification Morphology Identification clues include: • Shape and size of the cell • Type, number, and distribution of locomotor structures • Presence of special organelles or cysts • Number of nuclei

Important Protozoan Pathogens Pathogenic flagellates: Trypanosomes  Genus Trypanosoma  T. brucei – African sleeping sickness  T. cruzi – Chaga’s disease Infective amoebas: Entamoeba Entamoeba histolytica – amebic dysentery  Ingested cysts germinate in the small intestine  Trophozoites migrate to the large intestine and grow  They can invade the liver, lungs, and skin  Common symptoms include gastrointestinal disturbances Helminths (parasitic worms): Characteristics and major groups (types).  Multicellular animals  Parasitize (causes harm) needs host tissues Vs. Cominsum (Both parties benefit)  Have mouthparts for attachment to or digestion of host tissues  Most have well-developed sex organs that produce eggs and sperm  Fertilized eggs go through larval period in or out of host body

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Major Groups of Parasitic Helminths Flatworms – flat, no definite body cavity; digestive tract a blind pouch; simple excretory and nervous systems Cestodes (tapeworms) Trematodes or flukes, are flattened, non-segmented worms with sucking mouthparts Roundworms (nematodes) – round, a complete digestive tract, a protective surface cuticle, spines and hooks on mouth; excretory and nervous systems poorly developed Helminth Classification and Identification  Classify according to shape, size, organ development, presence of hooks, suckers, or other special structures, mode of reproduction, hosts, and appearance of eggs and larvae

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Identify by microscopic detection of worm, larvae, or eggs...