Micro Exam 3 PDF
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This document contains microbiology questions and answers. The quiz covers topics such as bacteria, protists, and various biological concepts. It is an exam or assessment. Subjects discussed include processes, structures, and characteristics related to biological organisms at a cellular and molecular level.
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=QUIZ 8 1. What carbohydrate(s) cannot be used by Rickettsia as a substrate for growth? - Glucose 2. Select all of the metabolic processesRhodospirillumrubrumis capable of utilizing when growing under anoxic conditions: Photoheterotrophy Photoautotroph...
=QUIZ 8 1. What carbohydrate(s) cannot be used by Rickettsia as a substrate for growth? - Glucose 2. Select all of the metabolic processesRhodospirillumrubrumis capable of utilizing when growing under anoxic conditions: Photoheterotrophy Photoautotrophy Fermentation 3. Match the statements to the organisms they describe in order to test your knowledge of notable protists. Giardia = Pathogen with mitosomes Trichonympha = Termite gut inhabitant Euglena = Flagellate photoautotroph wit a stigma Trypanosoma = Parasite that causes African sleeping sickness Entamoeba = Parasite that causes amoebic dysentery Phytophthora = Destructive pathogen of plants Physarum = Acellular (plasmodial) slime mold Dictyostelium = Cellular slime mold CategoryParamecium = Ciliate with a macro- and a micro-nucleus CategoryPlasmodium = Parasite that causes malaria 4. Sort these descriptions of amoeboid structures and cell characteristics to match the correct terms: ❖ Pseudopodia = False feet of rlocomotion and feeding ❖ Lobopodia = Rounded pseudopodia ❖ Filopodia narrow= Long, pseudopodia ❖ Reticulopodia = Netlike mesh of pseudopodia ❖ Testate amoebae = Plasma membrane covered by secreted or collected material ❖ Naked amoebae =Plasma membrane not covered 5. Asexual protist cell division is termedBinaryfission 6. Members of this bacterial genus can utilize oxygen under aerobic conditions and nitrate under anaerobic conditions as a terminal electron acceptor: - Escherichia 7. The sheath produced by Leptothrix cells mainly functions to: - accumulate large amounts of certain nutrients 8. You have isolated several bacteria from natural settings and they all stain Gram positive. Match each group of characteristics with the correct genus. F orms endospores, rod-shaped, facultative anaerobe, reduces nitrate when anaerobic, isolated from soil =Bacillus Cannot form endospores, grows as pairs and chains of cocci, strictly fermentative, isolated from an infected throat =Streptococcus Forms endospores, rod-shaped, obligate anaerobe, ferments amino acids, isolated from a gangrenous wound =Clostridium Cannot form endospores, grows as clusters of cocci, facultative anaerobe, uses nitrate when anaerobic, isolated from a skin wound =Staphylococcus 9. Compare and contrast the intracellular life cycles of Legionella and Coxiella by placing each attribute under the appropriate genus: Legionella - RFs reside in replicative endosomes - Grows within protozoan hosts - MIFs form Coxiella - Enters host cell via phagocytosis - LCVs form - SCVs form 10. How is the foram test used? - Oil companies use the test to help them find oil deposits. ATTEMPT 2 1. Species of Clostridium and Clostridium include obligately anaerobic, fermentative, Gram-positive bacteria that form endospores. These bacteria have great practical impact both in industry and as human pathogens. Identify some of the important species here: ❖ Clostridium acetobutylicum = blank is used to manufacture butanol. ❖ Clostridioides difficile = causes gastrointestinal disease. ❖ Clostridium botulinum = bills the causative agent of botulism. ❖ Clostridium tetani = is the causative agent of tetanus. 2. What arefourpractical impacts pseudomonads mayhave? T hey are major human pathogens and include a frequent causative agent of lung infections. Pseudomonasspecies can degrade many organic moleculesand are sought after for bioremediation. Studies of organism in this group have led to many advances in microbial physiology. They cause spoilage of milk, eggs, meat, and seafood. 3. Which of these bacterial genera would you expect to be capable of carrying out nitrification? (Check all that apply.) Nitrococcus Nitrobacter Nitrosomonas Match these slime mold genera with their growth habit: - P hysarum = Acellular slime mold - Dictyostelium = Cellular slime mold 6. Select the characteristics that help distinguish heliobacteria from other anoxygenic phototrophic bacteria: Heliobacteria are the only Gram-positive anoxygenic phototrophic bacteria. Heliobacteria have light harvesting pigments in their plasma membranes Heliobacteria possess bacteriochlorophyll g 7. Classify these attributes as applying to either streptococci or enterococci: Streptococci - Either alpha- or beta-hemolytic - Found in the mouth and respiratory tract - Can form biofilms - Cell wall contains M protein Enterococci - Can be alpha- or beta-hemolytic OR lack hemolytic abilities - Cell wall lacks M protein - Do not usually form biofilms - Found in the GI tract 8. Sort the descriptions into their corresponding bacterial types to organize information about characteristics of these important groups of Gram-positive bacteria. Clostridia = Endospore-forming strict anaerobes Bacilli = Diverse group of endospore-forming aerobes and fermenters Staphylococci = Skin inhabitants growing in grape-like clusters Lactobacilli = Acid-producing fermenters of foods Streptococci = Diverse group of human pathogens TTEMPT 3 A 1. Which protist organelle is used principally for maintaining osmotic stability? - Contractile vacuole 2. The class Negativicutes was recently established. Although these organisms have an outer membrane like Gram-negative bacteria, they are placed among the Gram-positive based on the analysis of what molecule? - 16S ribosomal RNA 3. Which of these characteristics pertaining to Bacillus subtilis help support the fact that it is an important model organism for the genus Bacillus and for other Bacillota (select all that apply)? B. subtilis is a facultative anaerobe that can use nitrate as a terminal electron acceptor. B. subtilis is the most well studied Gram-positive bacteria. B. subtilis is a nonpathogenic microbe. The genome of B. subtilis was one of the first bacterial genomes to be completely sequenced. DIMA 1. Which organelle is found in some organisms withinthe Discoba-Metamonada clade, but does not produce any ATP, despite its evolutionary history? oMitosome 2. Select all of the characteristics that apply toexospores of Streptomycetales. oCapable of withstanding desiccation o Form in response to nutrient deprivation oForm at the tips of aerial hyphae 3. Select all of these nutritional strategies thatare used by protists: oOsmotrophy o Holozoic nutrition o Saprotrophy o Mixotrophy o Photoautotrophy 4. Agrobacterium species.. o..stimulate tumor-like growths in plants to obtainnutrients. 5. The fusion of haploid protist cells is called oSyngamy 6. Assign these descriptions to their correspondingbacterial genera in the Actinobacteriota: oActinomyces:Prefers the oral cavity as a habitat oArthrobacter:Soil organisms displaying 'snapping'division oNocardia:Vegetative hyphae found in soils oCorynebacterium:Forms metachromic granules oMycobacterium:Cell walls contain mycolic acids oFrankia:Symbiotic nitrogen-fixing bacteria oPropionibacterium:Used in Swiss cheese fermentation oStreptomyces:Produces a wide range of antibiotics 7. Members of which bacterial family are typicallyoxidase negative? oEnterobacteriaceae 8. Match these protist structures with their most appropriate definition: oPellicle:Cell membrane including a rigid layerjust beneath it oEndoplasm:Inner fluid region oEctoplasm:Outer gelatinous region oCytostome:Cell 'mouth' oPlasmalemma:Cell membrane 9. Where could you find Trypanosoma cruzi fromthe group Discoba in nature? oGut of Triatominae ("kissing bugs") 1 0.The Gammaproteobacteria include important environmentalorganisms as well as pathogens such as Neisseria, which is the causative agent of: ogonorrhea. 1 1.Which bacteria can oxidize large amounts of ammonia-containingwaste, consuming so much oxygen in the process that they can create hypoxic areas of water? oNitrifying bacteria 1 2.Completing each sentence to review major characteristicsof members of Gammaproteobacteria: oA) The Gammaproteobacteria include important environmentalorganisms as well as pathogens such as Neisseria, which is the causative agent ofgonorrhea. oB) Another important group are chemolithotrophs- including Nitrosomonas - that oxidize ammoniato obtain electrons and releasenitrite. oC) Taking a different approach to nitrogen cyclingare organisms like Thiobacillus, which can be involved in denitrification but are known best for oxidizingsulfurcompounds tosulfate. Quiz 9 1.What does the term "zoosporic fungi" mean? - The spores of zoosporic fungi are dispersed via amphibians. 2.Classify these into their appropriate taxonomicgroups based on genome characteristics. dsDNAviruses - NCLD viruses - Herpesvirus - Escherichia virus Lambda - Escherichia virus T4 ssDNA viruses - phi X174 phage - Pf1 virus - Parvovirus dsRNA viruses - Rotavirus - Pseudomonas virus phi 6 plus-ssRNA viruses - Poliovirus - Tobacco mosaic virus (TMV) minus-ssRNA viruses - Ebola virus - Influenza virus - Measles virus - Rabies virus Retroviruses - Human immunodeficiency virus (HIV) Reverse transcribing DNA virus - Hepatitis B virus 3. Select the most appropriate word or phrase to complete this discussion of fungal saprotrophic nutrition: - Filamentous fungi are well suited to saprotrophs for at least two reasons. First, they secrete hydrolytic enzymes that enable thedegradationor decomposition ofcomplex o rganic nutrients. Second, their long hyphae increase thesurface area to volumeratio, which increases the rate of nutrient absorption. Together, these factors make it possible for fungi to use the process ofosmotrophyto acquirenutrients. 4. Which of these virus groups employ an enzyme called RNA-dependent RNA polymeraseto complete their life cycle (select all that apply)? - plus-ssRNA viruses - dsRNA viruses - minus-ssRNA viruses 5.Which of these statements describes the strategy adopted by a single-stranded DNA virus where the genome has the same base sequence as viral mRNA. - The single strand of DNA is used as a template to make a complementary strand of DNA, then transcription continues using the negative DNA strand as a template to make mRNA. 6. Single-stranded RNA viruses containing RNA sequences that are complementary to the mRNA produced upon their infection of a host cell are callednegative strandRNA viruses. 7. Common human pathogens amongmicrosporidiaincludeEnterocytozoon bieneusi, which causes diarrhea and pneumonia. 8. The body of a fungus usually consists of long, branched, threadlike filaments of cells called hyphaethat form a tangled mass calledmycelium. 9. Hepatitis B virus infectslivercells. 10. How do the genomes of HIV and influenza virus differ? - Influenza virus has a segmented, negative-stranded RNA genome, whereas the genetic material of HIV is not segmented and is positive-stranded RNA. Attempt 2 1. Single-stranded RNA viruses containing a RNA genome that is identical to mRNA are called positive strand bRNA viruses. True 2. Sexual reproduction in zygomycetes results in the production of zygospores. Meiosis often occurs just before germination of zygospores, generating new hyphae and the formation sporangia. What is the nuclear state of the spores within these sporangia? Haploid (1n) 3. Sexual reproduction in zygomycetes, ascomycetes, and basidiomycetes requires the participation of opposite or compatible mating types. Which of the following statements best explains the evolution of sexual reproduction in these fungi? A mating requirement for different, compatible mating types ensures that genetic diversity will be achieved. 4. Match the descriptions with the fungal organisms that they describe. Mycorrhizal fungi Form associations with plant roots CategoryChytrids Produce zoospores with a single posterior whiplash flagellum CategoryRhizopus Common bread (and fruit) mold Saccharomyces Model organism for studies of cell and developmental biology in eukaryotes CategoryUstilago Causal agent of smut on maize Candida Common opportunistic fungal pathogen in humans Agaricus Fruiting bodies are commonly used as food Cryptococcus Respiratory pathogen of humans and otehr animals Microsporidia Obligate intracellular parasites 5. Fungal species that are self-fertilizing and produce sexually compatible gametes on the same mycelium are termed: Homothallic 6. Complete each sentence about sexual reproduction in fungal species. a. Sometimes both the cytoplasm and haploid nuclei fuse immediately to produce the diploidzygote, as occurs in 'higher' eukaryotes. b. More often, there is a delay between cytoplasmic and nuclear fusion. This produces a dikaryoticstage in which cells contain two separatehaploid nuclei (N + N), one from each parent. c. After existing for some period of time in this state, the two nuclei fuse and undergo meiosis to yieldhaploidspores. d. This is seen in bothascomycetesand basidiomycetes,so these are sometimes referred to as dikaryotic fungi or Dikarya. 7. Select all the characteristics that apply to the phylum Olpidiomycota. icroscopic M May exist as a single cell, a small multinucleate mass, or form a true mycelium Produce zoospores with a single whiplash flagellum Display a variety of life cycles involving both asexual and sexual reproduction Saprophytic or parasitic Some members are capable of degrading cellulose and even keratin Attempt 3 1. The reverse transcribing virus, Hepatitis B virus, will obtain its mature viral genome from... ...a viral mRNA that has been reverse transcribed into DNA. 2. Fungi are found in nearly every habitat on earth, from environments that are very hot to very cold, as well as in lakes with high salt concentrations. True 3. The Baltimore group termed retroviruses are the only viruses that use reverse transcriptase. False 4. Many fungi are important __________ that degrade complex organic materials in the environment to simple organic compounds and inorganic molecules, such as carbon. Decomposers 5. 1. Which of these viruses requires a reverse transcriptase to produce new nucleocapsids? ○ Human immunodeficiency virus 2. W hich of these is NOT a mechanism that a virus could use to generate multiple proteins at once, instead of one single protein? ○ Viruses release cell signals upon entry that initiate translation for each particular protein. QUIZ 10 1.You are a marine microbiologist interested in the flux of carbon and nitrogen to waters beneath the photic zone. Which of the following predictions is most reasonable? Low levels of all nutrients - including carbon and nitrogen - will reach the deeper layers. 2. The difference between facultative and obligatory interactions between symbionts is that facultative organisms cannot live independently; symbiosis is crucial to their life cycle. False 3. Recent metagenomic investigations reveal that human microbiome is extremely diverse and both human and microbes benefit. The relationship is best described as: Mutualistic 4. Classify these statements and examples according to whether they refer to predatory or parasitic relationships: CategoryPredation Organism benefits from nutrients after the host is dead Vampirococcus attaches to the cell surface and secretes lytic enzymes that kill the cell Bdelllovibrio invades cytoplasm and consumes cell contents CategoryParasitism Organism benefits from nutrients while hte host is still alive Chlamydophila pneumoniae reproduces inside host cells and causes a respiratory infection Bacteriophage T4 injects its genome into an E. coli cell and 'hijacks' cell machinery for replicaiton 5. Match each process with an appropriate use. Metatranscriptomics —- Identification of the presence of amoB mRNA Metagenomics—-Identification of the presence of the anammox gene hzf Metaproteomics —-Identification of the presence of the nitrogenase enzyme 6. Assessing microbial community activity can use both biogeochemical and molecular techniques. Pair up the technique description with the name of the method it represents. Microelectrode= Probe for measuring chemical conditionsin microbial habitats. Stable isotope probing= Uses 'heavy' forms of elementsto trace metabolically active cells. Isotope fractionation= Allows the discriminationof either the source or the fate of different elements in the environment. Microcosm= Small laboratory incubation chamber thatmimics environmental conditions. ISRT-FISH= Uses fluorescent probes to detect cDNAsgenerated in whole cells. MAR= Uses radioactive substrates to identify metabolicallyactive cells in autoradiographs. 7. One advantage of measuring in situ mRNA abundance is... ...it demonstrates what genes are being actively transcribed. 8. Microelectrodes are commonly used to measure a variety of parameters, including (select all that apply)... pH Electron acceptor Oxygen tension Electron donors 9. Because so few organisms can be successfully cultivated in the laboratory, studying only those that have been isolated often doesn't give an accurate picture of what actually happens in nature or a true estimate of microbial diversity True 1 0. Bacteria in aquatic environments have evolved various mechanisms to maximize nutrient acquisition and retention. Why? Most aquatic environments lack a steady supply of nutrients, putting selection pressure on microbes to innovate mechanisms. Attempt 2 1. Match the microbial group with its most appropriate enrichment environment: Nitrogen oxidizing chemoautotrophs= Conditions withammonia and carbon dioxide Alkaliphilic chemoheterotrophs= Conditions with glucoseand pH of 9 Anoxygenic photoautotrophs= Conditions with carbondioxide , long wavelength light, and no dioxygen Heterocystic photoautotrophs= Conditions with carbondioxide , molecular nitrogen, and red/blue wavelength light Acidophilic chemoautotrophs= Conditions with carbondioxide and pH of 2 Microaerophilic chemoheterotrophs= Conditions withglucose and 5% oxygen 2. Patients who take antibiotics sometimes experience overgrowth of the fungus Candida albicans in their mouths and throats (a condition called thrush). C. albicans is considered part of the gastrointestinal microbiome but its population is typically limited by the presence of other microorganisms. Based on this evidence, which of the following types of symbiotic relationship do you think occurs between members of the normal flora and C. albicans? Competition 3. What are the fundamental characteristics of flow cytometry (select all that apply)? Cells are forced to pass by a laser beam, one at a time. Cells are tagged with a fluorescent dye. Cell size and morphology are determined by the scattering of light. 4. Choose the most applicable statement regarding freshwater on Earth: Polar ice and groundwater make up the majority of freshwater on Earth. 5. Microbial diversity can be assessed using a variety of methods. Pair up these methods and their key characteristics. FISH = Uses fluorescently-labeled probes and whole cells CARD-FISH = Uses horseradish peroxidase coupled to probes to enhance signal API = Uses a fluorescent stain (4',6-diamido-2-phenylindole) that binds to nucleic D acids Phylochip = Uses a microarray with SSU rRNA genes 6,Match each example with the appropriate type of growth inhibition: Contact-dependent growth inhibition: Salmonella ingested via undercooked chicken delivers a toxin into gut microbiome organisms using the T6SS projectile vehicle, inhibiting them and allowing Salmonella to occupy the niche and ultimately cause disease. Contact-independent growth inhibition: A bacterial species produces an antibiotic that diffuses through the medium and depletes organisms that are competing for nutrients and space.. 7.Viruses are at least 10 time less abundant that bacteria in both freshwater and marine ecosystems and play only a minor role in nutrient cycling. False 8.Analyze these statements and choose all that are true regarding the characteristics of a cooperative relationship: T he organisms that make up lichens can be described as having a cooperative relationship. Both organisms in a cooperative relationship can live independently of the other. A bacterium that contributes to the reproductive success of its host is in a cooperative relationship. 9. A major group of a-proteobacteria, also known aspelagibacterales (and first discovered in the Sargasso Sea), are estimated to make up 25% of all microbial life on the planet. Attempt 3 1. The oceans are strongly buffered by thecarbonateequilibrium system, which maintains the pH of seawater between pH 7.6 and 8.2. 2. Which of these statements about microbial communities found in lakes is correct? Shallow lakes have little mixing, and the photic zone reaches the lake bottom; thus autotrophs dominate the water column and benthic regions throughout the lake. 3. The relationship between the bacterium Xenorhabdus nematophila and its nematode host, Steinernema carpocapsae, is classified as cooperation because both organisms benefit and because... ...X. nematophila and S. carpocapsae can be grown separately. 4. Bacteria in aquatic environments have evolved various mechanisms to maximize nutrient acquisition and retention. Why? Most aquatic environments lack a steady supply of nutrients, putting selection pressure on microbes to innovate mechanisms. 5. In a mutualistic relationship between two organisms... ...both organisms benefit and often cannot live without each other. Dima 1. W hat techniques would be appropriate for assessing the microbial diversity in a gram of forest soil? More than one answer is possible. Phylochip analysis SSU rRNA analysis 2. Match the statements describing common terms used to characterize microbial ecological interactions to the appropriate terms. ○ Symbiosis:The physical association of two or moredifferent organisms. ○ Endosymbiosis:A symbiotic relationship between oneorganism and another one that lives inside it. ○ Ectosymbiosis:A symbiotic relationship between oneorganism and another one that lives on its surface. ○ Pathogen:An infectious agent that causes disease. ○ C oevolution:Evolutionary changes that occur within two or more organisms as a response to interactions between those organisms. 3. The source of nearly all organic matter in the open ocean (with the exception of the hydrothermal vent and subsurface chemolithoautotrophic communities) are the microbes that make up the: ○ phytoplankton. 4. Choose the most applicable statement about the characteristics of deep-sea subsurface microbes: ○ Deep-sea microbes must be able to tolerate atmospheric pressures up to 1,100 atm; some are obligate barophiles that must be cultured in hyperbaric incubation chambers. 1. A variety of culturing techniques are used in the laboratory to grow microorganisms. Select the terms to correctly complete the sentences describing some of the techniques used. a ) Microbial community analysis using culturing techniques require that the organism can be grownunder laboratory conditions. b ) Unfortunately, many environmental microbes will not grow in culture resulting in a disparity in the numbers that are observed microscopically, a phenomenon known as the great plate count anomaly. c ) Some of the organisms that do not grow in the laboratory are consideredviable but nonculturable. d ) In cases where a direct count on plates is not needed,enrichmentcultures can be used to select for organisms with certain capabilities. e ) These selective cultures can be used to quantify the number of viable organisms of a certain type usingmost probable numberanalysis. f ) High-throughput methods also take advantage of selective culture conditions using eitherextinction culturetechniques with high dilutionrates or themicrodroplet technique that involves encapsulation in a gel matrix. g ) The final goal of these techniques is a(n)axenicor pure culture of a single microbial strain. 2. Harmful algal blooms result when estuarine waters receive nutrients... ○ ...in a pulse-like fashion. 3. Y ou have isolated a soil protozoan, which you are now trying to grow in pure culture. You have tried many different types of media but find you can only grow the protozoan if bacteria are also present in the medium. You note that the bacterial population declines as the protozoan population increases. Based on this evidence, which of the following types of symbiotic relationships do you suspect might be occurring between the protozoan and the bacteria? ○ Predatory Quiz 11 1. Which of these statements correctly describes the activity of antibodies? Binding of antibody to biologically active materials (such as bacteria, toxins, or viruses) causes their inactivation or neutralization. 2. Cytotoxic T cells bear a receptor that is specific for class I MHC molecules presenting antigen; they are also known as CD8 cells. TRUE 3. Which of the following is NOT typical of the stem-nodulation process? Requires calcium spikes in the plant 4. Complete each of these sentences regarding the interplay between the innate and specific immune responses by selecting the best option: a) Macrophages and dendritic cells play a crucialrole in bridging the innate immune responses with adaptive immunity b ) Both cell types have membrane-boundpattern recognitionmolecules(PRMs), which bind to the microbe-associated molecular patterns (MAMPs) of pathogenmacromolecules c ) Once a pathogen is recognized by a phagocytic cell, the process of phagocytosisends with the antigenic remains of the microbe being presented on the surface of the cell where it is carried to thelymphoidtissue. d ) There, the antigens are presented to naïveT lymphocytes,which respond by stimulating additional lymphocytes to recognize that specific antigen and retain a memoryof its antigenic signature. 5. Different locations of the human body use different resistance strategies to help protect the human host from microbial invaders. Match each strategy with the correct location in the human host. resence of uric acid, fatty acids, mucin —-Genitourinarytract P Peristalsis —--Gastrointestinal tract Mucociliary blanket —--Respiratory system High concentration of sodium chloride —--Skin 6. The major histocompatibility complex (MHC) is a collection ofgenesthat code for the self/non-self recognition potential of an animal. 7. Thevariableregions of antibodies have differentamino acid sequences, and these regions fold together to form the antigen-binding sites. 8. Lysosomes contain a variety ofhydrolyticenzymes. 9.When a plant and microorganism interact with each other and both benefit, amutualistic relationship between the two organisms exists. 10. Which of these molecules can serve as antigens? Proteins, nucleoproteins, polysaccharides, and glycolipids Attempt 2 1. Which of these statements is correct about antigen presentation by class I and class II MHC molecules? he class I MHC molecule is presented on the surface together with its endogenous T antigen, enabling the host cell to present the antigen to a subset of T cells known as cytotoxic T lymphocytes. 2. Within the soil profile, most bacteria and archaea are found on the surface of soil particles 3. Leukocytes, or white blood cells, are the cells responsible for the innate defenses. Match each of these leukocyte types with a key characteristic: ast cell ==== A vasoactive mediator M Macrophage === The largest phagocytic cell in the body Basophil ==== A granulocyte that contains histamine Neutrophil======The principal phagocytic responder in blood Eosinophil ======Important in defense against protozoan and helminth parasites Monocyte =======Matures into a macrophage Dendritic cell=====Presents antigens to lymphocytes 4. If a host was unable to make interferon, it would make them more susceptible to infection by... iruses V 5. Classify these immunity types and their characteristics and examples of stimuli: Naturally-acquired active immunity Measles infection Immune system responds to infection Naturally-acquired passive immunity Transfer of antibodies through placenta to fetus Passage of antibodies through breast milk Artificially-acquired active immunity Intentional exposure to a foreign material Tetanus vaccine Artificially-acquired passive immunity Introduction of antibodies or lymphocytes from one host into another Administration of botulinum anmtitoxin 6.Match each of the plant diseases to its causative agent: rown gall ======Agrobacterium C Citrus canker ====Xanthomonas Gray mold ======Botrytis Chestnut blight ====Cryphonectria Late blight of potato ==Phytophthora Soft rot of potato =====Pectobacterium 7. Which of these statements about antigen-presenting cells is correct? endritic cells are particularly adept at presenting foreign peptides to T cells and D stimulating them to become activated T cells. 8. Which of these reasons account for the difficulty of lignin biodegradation (choose all possible reasons):. I t contains hundreds of phenylpropene rings Saturation with sap limits oxygen diffusion It contains microbe-inhibiting phenolics 9. A human host cell can defend against invading microorganisms using a variety of mechanisms. Viruses would be destroyed by the process of: Autophagy Attempt 3 1. Many different components play a role in the mammalian host immune system. Match these components of the immune response with the description of the role that they play. ntibody – A glycoprotein that binds to a specific antigen A Lysozyme –An antimicrobial chemical Antigen –A foreign substance that provokes an immune response Leukocytes –Can function in both innate and adaptive immunity 2.Penicillinis an example of a molecule that actsas a hapten. 3.Plants only respond to microbes in their habitat if those microbes are pathogens. True The complement system acts in a cascading fashion to (select all that apply): L ○ yse cell membranes of target cells ○ Produce inflammatory peptides ○ Enhance phagocytosis omplete these statements regarding plant/microorganism interactions by choosing the correct C term for each sentence: a) The area in the soil immediately around a plant's roots is called therhizosphere. b) This zone is influenced by plant rootexudates,which are more easily degraded than celluloses and lignin. c) Microorganisms also colonize the plant root surface or therhizoplane. d) As gases and soluble and particulate matter move from theplantto thesoil, this zone provides an ideal location for microbial growth. e) Another area of plant/microbe interaction is the area above the ground, where the stems and leaves grow. This is called thephyllosphere. f) The physical environment for this part of the plant is subject to notablefluctuationsof various factors, such as light and humidity. lassify these molecule types and statements according to whether they refer to cationic peptides C or bacteriocins: ○ Cationic Peptides: Defensins Cathelicidins Histatins ○ Bacteriocins: Lantibiotics Colicins Toxic chemicals produced by the normal microbiota What is a 'mycorrhiza'? ○ A fungus that has colonized a plant root and helps the plant take up phosphorus and other substances in exchange for plant nutrients. The presence of a granuloma is an indication ofa(n)... ochronic inflammation. A soil sample collected from a field contains 5% organic carbon. This soil would be called a(n): omineral soil
