Exam II Review Information Chapter 6 Viruses Define virus a host o What is meant by obligate intracellular parasite It must live inside a living cell must have o Compare contrast viruses to living cells VIRUSES cant reproduce on their own do not respond to stimuli no homeostasis and do not metabolize Describe virus structure with regard to o Capsid a coat of protein that is around the nucleic acid protects the genome gives the virus shape and is composed of sub units called capsomeres o Envelope outer envelope of fat protein and carbohydrates derived from the membrane of host cell and they have spikes that attach to host o Types and nature of nucleic acid Know the steps in the correct order for viral infection What events occur and what viral or cell structures proteins participate 1 Adsorption virus binds to the host cell 2 Penetration virus injects its genome into host cell 3 Uncaoated freeing the viral RNA into the cell cytoplasm 4 synthesis replication and protein production under the control of viral genes the cell synthesizes the basic components of new viruses RNA molecules capsomeres spikes 5 Maturation viral components assemble and viruses fully develop 6 Release newly produced viruses are expelled from the host cell What do the following terms mean Be able to name give at least 2 examples of each o Host range range of host species or cell types which a particular virus bacteria or parasite is able to infect or parasite EX hepatitis B can only infect liver cells and polio primarily infects nerve cells and intestines o Virion a fully formed extracellular virus that is virulent and able to establish infection in a host is called a viron EX virions attach to the host HIV is specific to where it only binds to a certain cell and so does same with influenza o Cytopathic effects virus induced damage to the cell that alters its microscope structural changes in a host cell resulting from viral infection CPE occurs when the infecting virus causes lysis dissolution of the host cell or when the cell dies without lysis because of its inability to reproduce Appearance EX inclusion bodies because the induce changes in the host and breakage and translocation leads to transformation to a tumor cell with loss of growth o Latency inactive over a long period of time EX herpes simplex and also chicken pox leads to shingles in adults o Teratogen Medicine any substance organism or process that causes malformations in a fetus Teratogens include certain drugs such as thalidomide infections such as German measles and ionizing radiation o Transformation permenatley alter the genetic material of the cell leading to cancer o Oncogenesis viruses that lead to cancer Leads to cancer EX HPV and Hepatitis More helpful info can be found at http www pc maricopa edu Biology rcotter BIO 20205 Assignments Unit 201 Unit1VirusesSpring2009 pdf Compare lytic and lysogenic bacteriophage replication KNOW THE STEPS LOOK AT POWER PT Why can t viruses be grown on a Petri dish of agar like bacteria How are they grown in the lab Because they have to have a live host For the viruses we studied in class HSV I and II and HIV know Correct name and type of virus what type of nucleic acid envelope or not enveloped Types of cells affected skins and mucous membranes Symptoms course of illness sensitivity burning when pee open lesions around mucous membranes like on mouth or gential Mode of transmission oral lessions or sex Chapters 7 9 Vocabulary Essential nutrient substance in food that must be obtained from the diet because the body cant make it in sufficient amounts Binary fission starts out as one then it splits into 2 Generation time the doubling time is the period of time for a quantity to double in size or value Gene DNA and chromosomes Nucleotide make up basic DNA and RNA molecules Replication DNA to DNA main enzyme is DNA polymerase Transcription DNA to RNA RNA polymerase Translation RNA to Protein Ribosome transcribes RNA to proteins Operon genetic regulatory system found in bacteria and their viruses in which genes coding for functionally related proteins are clustered along the DNA Inducer One that induces especially a molecule that is usually a substrate of a specific enzyme pathway combining with an active repressor produced by a regulator gene to deactivate the repressor Repressor Genetics A protein that binds to an operator blocking transcription of an operon and the enzymes for which the operon codes Mutation permanent change in the DNA sequence of a genes DNA sequence that can alter the amino acid sequence Nonsense mutation results in a smaller chain stop codon codes earlier Frame shift mutation addition or deletion of a nucleotide Conjugation a form of sexual reproduction in which results in an exchange of genetic information Plasmid circular DNA that replicate independently of bacterial chromosome Psychrophile cold temp Mesophile normal temp Thermophile hot temp Aerobe O2 Facultative anaerobe usually aerobic res but sometimes can transfer to anaerobic Obligate anaerobe must grow in the absence of O2 Acidophile flourish in acidity pH s Alkaliphile grows more likely in basic pH s Halophile like a lot of salt Metabolism all the chemical reactions in an organism Constitutive enzyme produced in constant amounts without regard to concentration of the substrate Induced enzyme enzyme produced by a cell in response to the accumulation or addition of a particular substance Redox reaction RIG Endospore Catalase helps break down a reaction Chapter 7 Elements of Microbial Nutrition What do the following terms mean micronutrient only needed in small amounts EX Fe helps produce red blood cells and Cl helps regulate water and electrolytes macronutrient needed in large amounts EX carbs proteins and fats trace element sometimes reffered to as micronutrients like iodine Know examples of each What are 3 ways bacteria adjust to limited nutrients Adjust metablolic rates utilize differet nutrients increase uptake and metablolis of nutrients Differences between simple and facilitated diffusion facilitated diffusion means that it needs a passage simple can just move across the membrane Differences between facilitated diffusion and active transport active needs energy What happens to cells placed in the following conditions isotonic hypertonic hypotonic What are the 4 stages of a bacterial growth curve Lag phase log phase stationary phase death decline phase What is happening in each of those 4 stages 1 Little to no division 2