Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Micro Final Practice
| Question | Answer |
|---|---|
| Virulence factors | Virulence factors are microbial traits (such as toxins, capsules, enzymes, and adhesion molecules) that enhance the ability to cause disease by promoting colonization, immune evasion, or tissue damage. |
| Microbial adhesion to host cells | Microbes adhere to host cells using adhesins (proteins, pili, or fimbriae) that bind specific receptors on host tissues, allowing colonization and preventing removal by mechanical defenses like mucus flow. |
| Capsules and cell wall components in pathogenicity | Capsules inhibit phagocytosis and help microbes evade immune recognition, while cell wall components (such as LPS or teichoic acids) can trigger inflammation and contribute to host tissue damage. |
| Coagulases vs. streptokinases vs. hyaluronidase | Coagulases promote clot formation to shield microbes from immune cells, streptokinases dissolve clots to facilitate spread, and hyaluronidase breaks down connective tissue to enhance tissue penetration. |
| Exotoxins vs. endotoxins | Exotoxins are secreted proteins with specific targets and high potency, whereas endotoxins are lipid components of Gram-negative cell walls that trigger strong inflammatory responses when released. |
| Mechanisms of major toxin types | A-B toxins inhibit essential functions (e.g., diphtheria toxin), cytolytic toxins disrupt membranes causing cell lysis, superantigens overstimulate T cells leading to cytokine storms, enterotoxins disrupt intestinal function causing diarrhea. |
| Types of immunity | Innate immunity provides immediate, nonspecific defense (e.g., skin, phagocytes), while adaptive immunity is specific and includes humoral immunity (antibodies) and cell-mediated immunity (T cells). |
| Three lines of defense | The first line includes physical and chemical barriers, the second line involves innate immune responses like inflammation and phagocytes, and the third line consists of adaptive immune responses with specificity and memory. |
| Herd immunity | Herd immunity occurs when a sufficient portion of a population is immune, reducing disease spread and protecting individuals who are not immune. |
| Types of disease transmission | Diseases can be transmitted through direct contact, indirect contact (fomites), droplets, airborne particles, vectors, or contaminated food and water. |
| Stages of disease | Disease progression typically includes incubation, prodromal, illness, decline, and convalescence stages, reflecting changes in symptom severity and pathogen activity. |
| Specific diseases | Influenza is an acute viral respiratory infection, tuberculosis is a chronic bacterial disease affecting the lungs, and HIV targets immune cells leading to immunodeficiency. |
| Antigenic shift vs. antigenic drift | Antigenic drift involves gradual mutations in viral antigens, while antigenic shift is a sudden reassortment of genes that creates new viral subtypes with pandemic potential. |
| Evolution | The process by which populations of organisms change over generations through genetic variation and natural selection. |
| Isotope Fractionation | The preferential use of lighter isotopes over heavier ones by enzymes during metabolic reactions, creating distinct isotopic signatures. |
| Hydrothermal Vents | Deep-sea openings in Earth's crust that release heated, mineral-rich water and support unique chemosynthetic microbial communities. |
| RNA Life | The hypothetical early stage of life when RNA molecules performed both genetic storage and catalytic functions before DNA and proteins evolved. |
| LUCA | The Last Universal Common Ancestor, the most recent organism from which all current life on Earth descended. |
| Small Subunit Ribosomal RNA | A highly conserved RNA component of ribosomes used as a molecular marker to study evolutionary relationships among organisms. |
| The Universal Tree of Life | A phylogenetic tree showing evolutionary relationships among all three domains of life: Bacteria, Archaea, and Eukarya. |
| LECA | The Last Eukaryotic Common Ancestor, the most recent common ancestor of all eukaryotic organisms. |
| Endosymbiotic Origin of Eukaryotes | The theory that mitochondria and chloroplasts originated from free-living prokaryotes that were engulfed and incorporated into early eukaryotic cells. |
| Homologs | Genes or proteins that share common ancestry and similar sequences across different organisms. |
| Orthologs | Homologous genes in different species that evolved from a common ancestral gene through speciation events. |
| Paralogs | Homologous genes within the same genome that arose through gene duplication events. |
| Gene Deletions in Microbial Genomes | The loss of genes from bacterial or archaeal genomes, often occurring when functions become unnecessary in specific environments. |
| Horizontal Gene Transfer | The movement of genetic material between organisms outside of traditional parent-to-offspring inheritance, common in prokaryotes. |
| Core Genome | The set of genes shared by all strains of a particular species, representing essential functions. |
| Pan Genome | The complete set of genes found across all strains of a species, including both core and accessory genes. |
| Building the Phylogenetic Tree | The process of constructing evolutionary relationships among organisms using genetic, morphological, or biochemical data. |
| Microbial Systematics | The scientific study of the diversity and relationships of microorganisms to classify them into organized groups. |
| Taxonomic Hierarchy | The system of nested categories (domain, phylum, class, order, family, genus, species) used to classify organisms. |
| Species | The basic unit of biological classification, defined in prokaryotes as groups with high genomic similarity and shared characteristics. |
| ANI | Average Nucleotide Identity, a measure of genomic similarity between bacterial strains used to define species boundaries (typically >95%). |
| Phenotypic Analyses | The characterization of observable traits and metabolic capabilities of organisms to aid in classification. |
| The Description of New Species | The formal process of characterizing and naming newly discovered organisms according to established nomenclature rules. |
| Bergey's Manual of Systematics of Archaea and Bacteria | The authoritative reference work for the classification and identification of prokaryotic organisms. |
| The Prokaryotes | A comprehensive reference handbook covering the biology, classification, and characteristics of bacteria and archaea. |
| Assimilative and Dissimilative Processes | Metabolic pathways that either incorporate nutrients into biomass (assimilative) or break them down for energy without incorporation (dissimilative). |
| Anoxygenic Photosynthesis | A type of photosynthesis that does not produce oxygen, using alternative electron donors like hydrogen sulfide instead of water. |
| Oxygenic Photosynthesis | The form of photosynthesis that uses water as an electron donor and releases oxygen as a byproduct, performed by cyanobacteria and plants. |
| Nitrification | The microbial oxidation of ammonia to nitrite and then to nitrate, an important step in the nitrogen cycle. |
| Denitrification | The microbial reduction of nitrate to nitrogen gas under anaerobic conditions, returning nitrogen to the atmosphere. |
| Methanogenesis | The microbial production of methane as a metabolic byproduct, typically occurring in anaerobic environments. |
| Fermentation | An anaerobic metabolic process that breaks down organic molecules to produce energy without using an external electron acceptor. |
| Syntrophy | A cooperative metabolic relationship where one organism's waste products serve as nutrients for another organism. |
| Enrichment Culture | A cultivation technique that selectively favors the growth of specific microorganisms by providing particular nutrients and conditions. |
| The Winogradsky Column | A laboratory microcosm used to study microbial succession and metabolic diversity in stratified sediment environments. |
| Culturomics | An approach using diverse culture conditions and high-throughput methods to cultivate previously unculturable microorganisms. |
| Phylogenetic Probes | Short DNA or RNA sequences designed to bind specifically to target organisms for identification based on genetic markers. |
| Fluorescence In Situ Hybridization (FISH) | A technique using fluorescent probes to visualize and identify specific microorganisms in environmental samples without cultivation. |
| 16S rRNA Gene Sequencing | The analysis of the highly conserved 16S ribosomal RNA gene to identify and classify prokaryotic organisms. |
| Metagenomics | The study of genetic material recovered directly from environmental samples without culturing individual organisms. |
| Microsensors | Tiny electrochemical probes used to measure chemical concentrations at microscale intervals in sediments or water columns. |
| Stable Isotope Probing (SIP) | A technique that uses isotopically labeled substrates to identify microorganisms actively metabolizing specific compounds in a community. |
| Symbiosis | A close, long-term biological interaction between two different species that can be mutualistic, commensal, or parasitic. |
| The Legume-Root Nodule Symbiosis | A mutualistic relationship where nitrogen-fixing bacteria (rhizobia) live in specialized root structures and provide fixed nitrogen to plants. |
| Mycorrhizae | Symbiotic associations between fungi and plant roots that enhance nutrient and water absorption for the plant. |
| Rhizobia | Soil bacteria that form nitrogen-fixing symbioses with legume plants by colonizing root nodules. |
| Primary Symbionts | Obligate endosymbionts that are essential for host survival and are vertically transmitted through generations. |
| Secondary Symbionts | Facultative endosymbionts that provide benefits to hosts but are not essential for survival and may be horizontally transmitted. |
| The Rumen and Rumen Activities | The specialized fermentation chamber in ruminant animals where diverse microbes break down plant material through anaerobic digestion. |
| Probiotics | Live microorganisms that, when administered in adequate amounts, confer health benefits to the host. |
| Prebiotics | Non-digestible food ingredients that selectively stimulate the growth or activity of beneficial gut microorganisms. |
| Synbiotics | Products that combine probiotics and prebiotics to synergistically promote beneficial gut microbiota. |
| Postbiotics | Bioactive compounds produced by probiotic bacteria during fermentation that provide health benefits to the host. |
| Causality | The relationship between cause and effect, particularly important in establishing whether microbes directly cause observed phenomena or are merely correlated. |
| The earliest RNA probably functioned in | both catalysis and self-replication. |
| LUCA is | the last universal common ancestor. |
| Which statement most closely expresses our present understanding? | The chloroplast arose from the incorporation of a cyanobacterial-like organism. |
| For microbial biodiversity studies, it is common to identify the ________ rather than the ________ as a measure of biodiversity. | genes / organisms themselves |
| When dealing with stable isotopes of carbon and sulfur, enzymes tend to favor | the lighter isotope. |
| For what purpose would a microbial ecologist use a microsensor? | To determine the concentration of O₂, N₂O, or other chemical species in small increments in a sediment or water column |
| Genes encoding ________ are widely used as target genes in molecular biodiversity studies. | 16S rRNA |
| Which of the following techniques can link prokaryotic phylogeny and metabolic function? | Environmental genomics and stable isotope probing |
| The overall purpose of DGGE is to | separate genes of the same length that have different sequences, resulting in different denaturation profiles. |
| The function of leghemoglobin in root nodules is to | bind oxygen. |
| -- Complete the short answer questions and generate some of your own |
Created by:
smurtab