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Download Microbiology Exam #1 (Chapter 1,3,4,5,6) Questions And Answers 2025/2026 and more Exercises Microbiology in PDF only on Docsity!
Microbiology - Correct Answer The specialized area of biology that deals with organisms too small to be seen with the naked eye 6 major groups of microorganisms - Correct Answer 1. Bacteria 2. Algae 3. Protozoa 4. Helminths 5. Fungi 6. Viruses What do microbiologists study? - Correct Answer - Cell structure - Growth and Physiology - Genetics - Taxonomy and evolutionary history - Interactions with living and non living environment What are the 6 different branches of study in microbiology? - Correct Answer 1. Medical microbiology 2. Public Health microbiology and Epidemiology 3. Immunology 4, Industrial Microbiology 5. Agricultural Microbiology 6. Environmental Microbiology Medical Microbiology - Correct Answer Study of microbes as they relate to medicine, deals with microbes that causes disease in humans and animals Public Health Microbiology and Epidemiology - Correct Answer Monitor and control the spread of disease in communities. USPHS, CDC, WHO. Industrial Microbiology - Correct Answer - Use of microbes to manufacture important compounds - Safeguards our food and water - Also includes biotechnology - Ranges from bread making to gene therapy - Microbes can be used to create large quantities of substances such as amino acids, beer, drugs, enzymes, and vitamins Agricultural Microbiology - Correct Answer - Deals with the relationships between microbes and domesticated plants and animals - Plant specialists focus on plant diseases, soil fertility, and nutritional interactions - Animal specialists work with infectious diseases and other associations animals have with microorganisms Immunology - Correct Answer Studies a diverse areas such as vaccination, blood testing, and allergy. Immunologists investigate the role of the immune system in cancer and autoimmune diseases Environmental Microbiology - Correct Answer Studies the effect of microbes on the earth's diverse habitats. Example- aquatic microbiology, soil microbiology, geomicrobiology, and astrobiology eu-kary means? - Correct Answer true nucleus; cells with a nucleus are classified as eukaryotes Pro-kary means? - Correct Answer Pre-nucleus; bacteria and archaea do not have a nucleus and have been traditionally classified as prokaryotes What is a microbe? - Correct Answer A microorganism How are biology and microbiology different? How are they similar? - Correct Answer Biology is concerned with all the different scales of size that microorganisms exist on, but many fields on biology - Example: A Microbiologist at the CDC may examine a culture of the influenza virus in order to understand why is is so harmful Public Health Microbiology & Epidemiology - Correct Answer - Monitor and control the spread of diseases in communities - CDC, USPHS, & WHO - Example: Epidemiologists conduct interviews as a part of the effort to curb the cholera epidemic in Haiti Immunology - Correct Answer - Studies the web of protective substances and cells produced in response to infection - Vaccination, blood testing, and allergy - Immunologists investigate the role of the immune system in cancer and autoimmune diseases - Example: Immunologists freeze dry samples of infectious diseases Industrial Microbiology - Correct Answer - Branch of microbiology in which microbes are manipulated to manufacture useful products - Ranges from bread making to gene therapy - Safeguards our food and water - Microbes can be used to create large quantities of substances such as amino acids, berm drugs, enzymes and vitamins - Example: Scientists use a multispectural imaging systems for inspection of chickens to be manufactured Agricultural Microbiology - Correct Answer - Concerned with the relationship between microbes and domesticated plants and animals - Plant specialists focus on plant diseases, soil fertility, and nutritional interactions - Animal specialists focus on infectious diseases and other associations animals have with microorganisms Environmental Microbiology - Correct Answer - Studies the effect of microbes on the Earth's diverse habitats - 4 Types: Aquatic, Soil, Geo, and Astro - Studies microbes in the earths surface water, soil, crust, and places off of our planet What type of cells originated first on planet Earth? What type of cells evolved next? What type of organism evolved last? - Correct Answer Prokaryotic cells originated fist, followed by Eukaryotic cells, and lastly viruses Photosynthesis - Correct Answer Light-fueled conversion of carbon dioxide to organic material, accompanied by the formation of oxygen What kind of organisms can proceed with photosynthesis? - Correct Answer Bacteria and Algae What is decomposition? - Correct Answer Breakdown of dead matter and wastes into simple compounds that can be recycled What type of organisms can proceed with decomposition? - Correct Answer Bacteria and Fungi Genetic Engineering - Correct Answer Manipulates the genetics of microbes, plants, and animals for the purpose of creating new products and genetically modified organisms (GMOs) Recombinant DNA Technology - Correct Answer Techniques that allow the transfer of genetic material from one organism to another and deliberately alter DNA Bioremediation - Correct Answer Introduction of microbes into the environment to restore stability or to clean up toxic pollutants Biotechnology - Correct Answer Manipulation of microorganisms to make products in an industrial setting What is the difference between a pathogen and a microbe? - Correct Answer A pathogen is a microorganism that has the potential to cause disease, but microbes are not always pathogens What is John Tyndall responsible for in Microbiology? - Correct Answer Found that microbes in the dust and air have high heat resistance What is Ferdinand Cohn responsible for in Microbiology? - Correct Answer - Discovered and described bacterial endospores - Discovered Sterile, which is completely free of all life forms including endospores and virus particles What are Ignaz Semmelweis, Dr. Oliver Wendell Homes, and Joseph Lister known for in Microbiology? - Correct Answer Dr. Oliver Wendell Holmes and Dr. Ignaz Semmelweis - Development of Aseptic techniques. Showed that women became infected in the maternity ward after examinations done by physicians who had been working in the autopsy rooms. Joseph Lister - First to introduce aseptic technique and utilize hand washing and misting operating rooms with antimicrobial chemicals. These techniques are still used today What are Luis Pasteur and Robert Koch responsible for in Microbiology? - Correct Answer Luis Pasteur - Contributed to the microbial fermentation role in wine and beer production, invented pasteurization, showed that human diseases could arise from infection Robert Koch - Established Koch's postulates, a series of proofs that verified the germ theory of disease, linked a specific microorganism with a specific disease (Anthrax- Bacillus anthracis). Also developed numerous lab techniques What is spontaneous generation? - Correct Answer The theory that life appears from nonliving things Who is responsible for disproving spontaneous generation? - Correct Answer Luis Pasteur Who verified the germ theory? - Correct Answer Robert Koch Describe the steps in order for the Scientific Method - Correct Answer 1. Make an observation - through experience, thoughts, or reading 2. Conduct background research - learn more about what you have observed Make a hypothesis - form a question to be tested and answered 3. Experiment - Test the question with an experiment 4, Observe outcome - Observe what is seen from the experiment 5. Analyze data and draw conclusions - Explain what was seen and whether or not the hypothesis was corrrect 6. Develop a theory backed by research What is a theory? - Correct Answer A well tested explanation that unifies a broad range of observations What is the field of taxonomy? - Correct Answer Science of classifying living things Nomenclature - Correct Answer Assignment of scientific names to the various taxonomic categories and individual organisms Classification - Correct Answer Attempts the orderly arrangement of organisms into a hierarchy of taxa (categories) Identification - Correct Answer Process of discovering and recording the traits of organisms so they can be recognized and placed in a taxonomic scheme What are the 8 levels of classification from general to specific? - Correct Answer Domain Kingdom Phylum Class Order Family Genus Species Leishmaniasis - Protozoa Gonorrhea - Bacteria Ringworm - Fungus The accumulation of changes that occurs in organisms as they adapt to their environments - Correct Answer Evolution Consist of prokaryotic cells and Staphylococcus aureus and Escherichia Coli are examples of this organism - Correct Answer Bacteria What type of microbe is classified as a tiny infectious particle? - Correct Answer Virus List the taxonomic categories in order from general to specific - Correct Answer - Domain - Kingdom - Phylum - Class - Order - Family - Genus - Species The purposeful addition of a specimen into/onto culture medium - Correct Answer Inoculation A microscopic cluster of cells that originated from a single cell - Correct Answer Colony What type of medium allows multiple types of microbes to grow but is designed to show visible color differences among those organisms? - Correct Answer Differential What type of microscope uses visible light and produces well-defined, three-dimensional images? - Correct Answer Compound microscope What type of dyes are used in positive staining and are attracted top the negatively charged cell? - Correct Answer Basic Name several specimens that can be collected for culturing microorganisms, then name the five I's in order. - Correct Answer Nearly any object or material can be collected for culturing microorganisms, common ones are body fluids and tissues, foods, water, or soil. Five I's: - Inoculation - Incubation - Isolation - Inspection - Identification Inoculation - Correct Answer - Sample is placed into a container of sterile medium - Cultivation of microorganisms - Involves spreading the sample on the surface of a solid medium or introducing the sample into a flask or tube Incubation - Correct Answer - An incubator creates the proper growth temperature and other conditions - Promotes multiplication of the microbes over a period of hours, days, and even weeks. - Produces a culture - the visible growth of the microbe in or on the medium Isolation - Correct Answer Microbes may take the form of separate colonies on solid media, or turbidity in broths. Single species of microbe Inspection - Correct Answer - The colonies or broth cultures are observed microscopically for growth characteristics (color, texture, size) that could be used in analyzing the specimen contents Identification - Correct Answer - Microbial profiles are determined y phenotype testing, genotype testing, macroscopic and microscopic analysis What is the difference between a cell and a colony? - Correct Answer - A cell us a unit of a colony - Acolony has millions of cells - Acolony can be even by the naked eye, but a cell needs a microscope Is a cell considered to be microscopic or macroscopic? - Correct Answer Microscopic Is a colony considered to be microscopic or macroscopic? - Correct Answer Macrascopic Transport media - Correct Answer Maintains and preserves specimens Assay media - Correct Answer Used to test the effectiveness of antimicrobial drugs Enumeration media - Correct Answer Used in industrial and environmental microbiology Carbohydrate fermentation media - Correct Answer Contains sugars and pH indicators to show fermentation Describe the 3 different methods of isolating bacteria. - Correct Answer - Streak plate: a small droplet of culture or sample is spread over the surface of the medium with an inoculating loop in a pattern that gradually thins out the sample and separates the cells spatially over several sections of the plate - Loop dilution: the sample is inoculated serially into a series of cooled but sill liquid agar tubes so as to dilute the number of cells in each successive tube in the series. - Spread plate: a small volume of liquid, diluted sample is pipetted onto the surface of the medium and spread evenly by a sterile spreading tool Mixed culture - Correct Answer Two or more species of bacteria Pure culture - Correct Answer Only one species of bacteria Contaminated Culture - Correct Answer Contains contaminants or intruders What is a subculture used for? - Correct Answer It is used to make a second-level culture from a well- isolated colony A standard method for making a pure culture How are biochemical tests, genotypic tests, and immunologic tests used in inspection and identification of cultures? - Correct Answer - Biochemical tests can determine fundamental chemical characteristics such as: Nutrient requirements, products given off during growth, presence of enzymes, & mechanisms for deriving energy - Genotypic testing detects Microbes based on their DNA - Immunologic testing tests the isolate against known antibodies Where are cultures disposed of after you are done with them? - Correct Answer Stream sterilization (autoclaving) or incineration are used to destroy microorganisms A microscope has a total magnification of 850x when using the ail immersion objective lens. What is the power of the ocular lens? - Correct Answer 8500 Magnification - Correct Answer Total magnification = power of ocular lens x power of objective lens Resolution - Correct Answer Distinguishes or separates two adjacent objects or points fram one another Contrast - Correct Answer Degree of contrast from the surroundings. Iris diaphragm controls the amount of light entering the condenser What is the difference between using the virtual and real image when using a microscope? - Correct Answer The objective lens forms the initial image of the specimen which is the real image. The virtual What is the purpose of making a wet mount or hanging drop technique in a Microbiology lab? - Correct Answer Fluid maintains viability and priories a medium for movement. Also provides a true assessment of size, shape, arrangements, color, and motility of cells What is the difference between positive and negative staining? - Correct Answer Positive charged dye sticks to the cell, gives it color, and is attracted to negatively charged cell walls. Negative charged dye is repelled by negatively charged bacterial cell walls. What is the difference between a simple, differential, and special stain? - Correct Answer - Simple: require a single dye, uncomplicated procedure - Differential: uses 2 differently colored dyes to contrast cell types, or cell parts. Complex staining technique - Special: Emphasize certain cell parts that are not revealed with conventional staining procedures Which stain provides more information: simple or differential stain? - Correct Answer Differential stain Name the four structures that are found in all bacteria - Correct Answer Cell membrane Ribosomes Cytoplasm Bacterial chromosomes in the nucleoid region What are the 3 general shapes (morphology) for bacteria? - Correct Answer Cocci Spirilla Bacilli Name the flagellar arrangement when flagella are located at both poles of the cell - Correct Answer Amphitrichous cells contain two layers in their cell envelope - Correct Answer Gram positive cells have an outer membrane made up of lipopolysaccharide (LPS) - Correct Answer Gram negative What us the total size for a bacterial ribosome? - Correct Answer 70S Clostridium, Bacillus, and Sporosarcina produce dormant highly resistant - Correct Answer Endospores Unique prokaryotic cells that are more closely related to Domain Eukarya than to Domain Bacteria - Correct Answer Archaea Bergey's manual of is based on phenotypic characteristics and is used in clinical, teaching, and research labs - Correct Answer Determinative Bacteriology What is the structure and function of a bacterial flagellum? Describe the three parts of the bacterial flagellum. - Correct Answer Composed of proteins. Three parts: - Basal Body: a stack of rings firmly anchored through the cell wall to the body - Hook: anchored to the cell by the basal body - Filament: helical structure, composed of proteins, approximately 20 nanometers in diameter. Inserted into a curved, tubular hook Describe the different arrangements for bacterial flagella. - Correct Answer - Monotrichous polar: single flagellum - Lophotrichous polar: several tufts emerging from same site - Amphitrichous polar: flagella at both ends - Petritichous: flagella randomly dispersed over the entire surface of the cell Biofilms - Can infect long-term in dwelling artificial devices such as plastic catheters, intrauterine devices, and metal pacemakers Describe the structure of peptidoglycan in the bacterial cell wall. - Correct Answer Peptidoglycan is found in the cell walls of bacteria. It is a unique macromolecule composed of gylcan chains cross linked with short peptide fragments. Also provides a strong but flexible support framework Describe the differences between Gram-positive and Gram-negative cells. - Correct Answer Gram positive cells have a thick layer of peptidoglycan 20-80nm thick and gram negative cells have a thin layer of peptidoglycan 1-3nm Mycoplasma and other cell-wall-deficient bacteria lack a bacterial . Name the most important medically species of Mycoplasma. - Correct Answer Cell wall. The most important species is What is the structure and function of the Gram-negative outer membrane? - Correct Answer - Contains specialized polysaccharides and proteins - Lipopolysaccharide - Polysaccharide chains function as antigens and receptors What is the structure and function of the bacterial cell membrane? What is typically absent in the bacterial cell membrane but present in a eukaryotic cell membrane? - Correct Answer - The cell membrane is a phospholipid belayer embedded with proteins completely around the cytoplasm - The cell membrane transports the nutrients into the cell and discharges wastes. - It is selectively permeable, water and small uncharged molecules diffuse freely, and special carrier mechanisms may exist. - Secretes discharge of metabolic products into the extra cellular environment What is the structure and function of the bacterial cytoplasm, chromosome/nucleoid, plasmids, ribosomes, inclusion bodies or microcompartments, and cytoskeleton? - Correct Answer CYTOPLASM: - Gelatinous solution contained by the cell membrane. - Prominent site for the cells biochemical and enzymatic activities - 70-80% water, complex mixture of sugars, amino acids, and salts - Also contains chromatin, ribosomes, granules, and fibers that act as the cytoskeleton BACTERIAL CHROMOSOME: - Typically only one and found in a circular appearance - Aggregated in a dense area called the nucleiad - DNA is tightly coiled around protein molecules PLASMIDS: - Non-essential pieces of DNA - Separate, double stranded circles of DNA - Confer positive traits - Duplicated and passed onto offspring during replication - Important in genetic engineering RIBOSOMES: - Made of rRNA and protein - Dispered throughout the cytoplasm - Svedberg (S) units: Measurement of the relative size of cell parts through sedimentation during centrifugation - Bacterial ribosomes: 70S - Eukaryotic ribosomes: 80S INCLUSION BODIES: - Storage sites for nutrients during period of abundance - Single-layered membranes - Vary in size, number, and content MICRO-COMPARTMENTS: - Made of protein 
