EXAM QUESTIONS:ANSWERS.pdf

Exam 1Exam 1: ( Unit 1 & Unit 2 section 1) Chapters 1, 3 and 8 Unit 1. Section 1: chapter 1, chapter 3.1, chapter 3.2 Intro What is a microorganism? Organism too small to see with the naked eye Chapter 1.1 How did early civilizations handle the correlation between sewage and disease? Aqueducts were...

Exam 1Exam 1: ( Unit 1 & Unit 2 section 1) Chapters 1, 3 and 8 Unit 1. Section 1: chapter 1, chapter 3.1, chapter 3.2 Intro What is a microorganism? Organism too small to see with the naked eye Chapter 1.1 How did early civilizations handle the correlation between sewage and disease? Aqueducts were built to carry waste away What were the main contribuions of each individual to the early notions of disease? a) Hippocrates – “Father of Western Medicine” diseases were natural causes rather than supernatural causes b) Thucydides – “Father of Scientific History” advocate for evidence based analysis of cause and effect c) Marcus Terrentious Varro – proposed that things we cannot see (microorganisms) can cause disease What were the main contributions of each individual to the field of microscopy? a) Zacharias Janssen – first simple microscope b) Robert Hooke – impoved the microscope with fine adjustment, lighting, specimen holder c) Antony van Leeuwenhoek – “Father of Microbiology” developed a lens to view microbes Why is Antony van Leeuwenhoek known as the father of microbiology? The first to view microbes under a lens aswell ass record observations of muscle fibers, sperm, blood flow Regarding the Golden Age of Microbiology, a) What two scientists that we discussed were pivotal in advancing our understanding of the unseen world? What were the main contributions of each scientist during this time? Louis Pasteur - developed germ theory, disproved spontaneous generation, created vaccines for rabies Robert Koch – idenfified specific pathogens for cholera, anthrax What is the significance of the attenuation principle? Reduced the danger of pathogens Chapter 1.2 What is taxonomy? Classification of living organisms What were the main contributions of each scientist to the field of taxonomy? a) Carolus Linnaus – the binomial comenclature, a system for categorizing species b) Ernst Haekel – proposed the fourth kingdom of taxonomy including protista and monera c) Robert Whitaker – proposed a five kingdom, adding fungi aswell as the empire or superkingdom d) Carl Woese – three domains of life (bacteria, archaea, eukarya) What is a phylogenetic tree? “The tree of life” arranging organism by how related they are What are the 6 current kingdoms? Animalia, Plantae, Fungi, Protista, Archaea, Bacteria What are the 3 current domains? Bacteria, Archaea, Eukarya What are the eight taxonomic ranks in order from highest to lowest? Domain – Kingdom – Phylum – Class – Order – Family – Genus – Species How do we write the name of an organism using the binomial system? Both names are italicized, only genus capitalized What kind of information would I look up in Bergey’s manual? Classifying and identifying prokaryotes Chapter 1.3 Metric equivalents on Table 1.1 for millimeter, micrometer, and nanometer Meter Decimeter – 1/10 Centimeter – 1/100 Millimeter – 1/1000 Micrometer – 1/1,000,000 Nanometer – 1/1,000,000,000 What is the limitation of the human eye?.1mm or 100 micrometers What are the average sizes of animal, bacterial cells and viruses? Animal cell = 10micrometers, Bacterial cell = 1 micrometer, Virus = 0.1 micrometer Viruses do not fall within any of the three domains of life. What are the cells of bacteria made up of? Cell wall, plasma membrane, cytoplasm, ribosomes, DNA What are the common shapes of bacteria? Bacilli (pill shaped), Cocci (ball shaped), Spirillum Spirochete Vibrio (spiral shaped) What is one noteworthy aspect of Archaea? Can live in extreme environments, such as very hot, very cold, very basic, very acidi What are some common applications of algae? Biofuels, food product, pharma, and O2 for aquatic environments How are protozoa classified? Based on their movement mechanisms (cilia, flagella, pseudopods) What are some unique characteristics of fungi? Can be unicellular (yeast) or multicellular (mold), are decomposers, most grow in warm moist places What is the main difference between yeast and mold forms of fungi? Yeast is unicellular, used for foods, and causes diseases Mold is multicellular, used for pharma and causes allergies What are helminths? Multicellular parasitic worms, associated with microscopic eggs and larvae that causes diseases What makes up the structure of a virus? Why are viruses not considered alive? Virus consist of DNA or RNA, not considered alive because they don’t reproduce nor carry out metabolism What are some subfields of microbiology? Bacteriology - study of bacteria Mycology – study of fungi Protozoology – study of protozoa Parasitology – study of helminths and other parasites Virology – study of viruses Immunology – study of the immune system Chapter 3.1 What is abiogenesis? Explain how the experiments of Francisco Redi and Louis Pasteur disproved the theory. How did these experiments differ from each other? Life can spontaneously form from non living matter Francisco Redi disproved by proving decaying meat came from fly eggs Louis Pastuer disproved by microorganism don’t grow in sterile broth unless exposed by air Chapter 3.2 What does the cell theory state? All cells only come from other cells What was Robert Hooke’s important discovery when observing cork under the microscope? Discovered cells on cork and called them “cells” What does the germ theory state? Diseases may result from microbial infection What was the key finding of Ignaz Semmelweis during his inquiry into the births at Vienna General Hospital? Handwashing in lime solutions reduced the mortality rate in childbirth How was John Snow able to pinpoint the source of a cholera outbreak in 1848? Mapped cases and traced them to a contaminated water pump as the source of the outbreak What was Joseph Lister’s solution to the issue of deaths from postoperative infections? Carbolic acid to wrap wounds What was Florence Nightingale’s major contribution to the field of epidemiology? Used statistics to demonstrate preventable causes of death with infections, sanitation and hygiene What are the four Koch’s postulates? 1. The microbe must be present in every sick case 2. The microbe must cultured outside the body 3. Microbe must cause disease when given to same healthy species 4. Microbe must be reisolated from the experimental host What are some exceptions to Koch’s postulates? 1. Microbe not always isolated outside body 2. Some pathogens cause many diseases 3. Some pathogens may cause disease in specific host What is the modern focus of the germ theory of disease? 1. Antibody resistance 2. New diseases, and diseases with multiple organisms 3. Mechanism of microbial agents Unit 1. Section 2: chapter 3.3 Intro What structures are shared by both eukaryotes and prokaryotes? Plasma membrane, cytoplasm, ribosomes and DNA What structures are unique to prokaryotes and which are unique to eukaryotes? Prokaryotes – circular DNA, cell membrane, cytoplasm, bacterial flagella Eukaryotes – linear DNA, plasma membrane, endomembrane, mitochondria, chroloplats, flagella, cilia How is DNA stored differently in prokaryotes versus eukaryotes? Prokaryotes - stored DNA in a singular circular chromosome in nucleoid Eukaryotes – stored DNA in multiple linear chromosomes in nucleus What is the difference between the terms “cytoplasm” and “cytosol”? Cytoplasm – all cell structures and fluid Cytosol – just the fluid What are the differences between the flagella of eukaryotes and prokaryotes. Prokaryotes flagella – simpler, rotate to propel the cell Eukaryotic flagella – complex, whip like motion Chapter 3.3 What is the typical form of reproduction in bacteria? Binary fission, cell divides into two daughter cells What does it mean for a bacterium to be pleomorphic? To vary in size and shape What are some of the arrangements that bacteria have? Diplo -pairs Chains – strepto Clusters- staphylo Tetrads What is the glycocalyx? Gelatin layer surrounding the t outside of some bacteria cells What are the two forms of glycocalyx and how do they differ? Capsule – well organized, tightly attached form Slime Layer - less organized, loosely attached What are some functions of the glycocalyx? Traps nutrients, attaches to surfaces, evades the host white blood cells What is the main function of a flagellum? Mobility for bacteria to respond to environmental stimuli What are some basic arrangements of flagella? Monotrichous - one flagellum Amphitrichous – 1 flagellum or more at each end Lophotrichous – cluster of flagellum at one end Peritrichous - flagellum all around What are the components of a flagellum? Filament – outermost region that extends Hook – connects filament to cell surface Basal body – anchors flagellum to the cell wall and plasma membrane What is the main difference between the basic structure of flagella in Gram positive versus Gram negative cells? Gram positive flagella – 1set of rings, single membrane, thick petidoglyan layer Gram negative flagella - 2set of rings, two membrances(outer and inner), thin peptidoglycan layer How does a flagellum generate movement? By changing the rotation of their flagella How does a flagellum’s path of movement differ under no stimulus versus receiving a chemical attractant? No stimulus – more tumbling because of no chemical attractant therefor no sense of direction Stimulus – more running because of chemical attractant present therefor sense of direction What type of bacteria have endoflagella? Spirochetes What are fimbrae and what is their primary function? Used to attach to specific surfaces What is the primary function of a pilus? Bacterial conjugation, the transfer of genetic material between bacteria What is the primary function of the cell wall? Maintains bacterial shape and prevents cell fom bursting What is the polysaccharide found in bacterial cell walls? Peptidoglycans What are the two monomers, along with tetrapeptides, that make up peptidoglycan? N-acetylglucosamine (NA)G and N-acetylmuramic acid (NAM) What are the main differences between Gram positive and Gram negative bacterial cell walls? Gram Positive cell walls – thin peptidoglyvan layer and has teichoic acids Gram Negative cell walls – thin peptidoglycan layer,outer memebrane wirh LPS What macromolecules are found in the outer membrane of Gram negative cells? Lipopolysaccharides(LPS). Proteins and phospholipids What does it mean to say that lipid A is an endotoxin? Cause a strong immune response How do porins in Gram negative cells serve as virulent factors? Selectve permeable for nutrients and can evade host immune system by limting antibiotics What bacterium does not have a cell wall? Mycoplasma bacteria What does the fluid mosaic model of the cell membrane state? Cell membrane is dynamic, flexible sutrcutre composed of a phospholipid bilayer with fluidly moving proteins How are phospholipids both hydrophilic and hydrophobic? Has hydrophilic phosphate head and a hydrophobic fatty acid tails What are endospores? Under what conditions are they made? Highly resistant, dormant structures formed by bacteria under harsh environment Unit 2. Section 1. Chapter 8: Microbial Metabolism ( Skip 8.3) Chapter 8.1 1) What are the differences between catabolic and anabolic reactions? Catabolic – large molecules broken down into smaller ones, releasing energy Anabolic – smaller molecules assembled into larger ones, using energy 2) What is metabolism and how is energy stored in cells? All chemical reactions within a cell to maintain life, energy is stored as ATP in cells 3) What are enzymes? How do they work? Enzymes are catalyst to soeed uo chemical reactions, the bind subtrates to their active site 4) What are cofactors and coenzymes? Cofactor – non protein, inorganic partner for enzyme conformation Coenzyme – organic cofactors derived from vitamins such as NAD or FAD 5) What is an active versus allosteric site? Active site – region of enzyme where substrate binds Allosteric Site – a site other than active site where a molecule can bind 6) Explain the differences between the three mechanisms of pathway modulation: Feedback inhibition, Non-competitive inhibition, Competitive inhibition Competitive Inhibition – competes for active site with substrates Non competitive inhibition 0 binds outside active site, alters shade, prevents enzyme from binding Feedback inhibition – end product of a metabolic pathway inhibits an enzyme Chapter 8.2 7) What process breaks down glucose into 2-pyruvate? Glycolysis 8) What are the two phases of glycolysis and what are the main events that happen in each? Energy investment phase - glucose is phosphorlated using 2 ATP molecules Energy payoff phase - 3 carbon molecules are further processed, generating 4 ATP, 2 NADH, and 2pyruvate 9) Explain the differences between the three major pathways of glucose catabolism? aerobic respiration, anaerobic respiration, anaerobic fermentation Aerobic Respiration – uses oxygen as final electorn acceptor Anaerobic Respiration – doesn’t use oxygen but alterantive electron acceptor Anaerobic Respritation - occurs in the absence of oxygen and electron trian 10) What are the coenzymes