Bio 3401 Final Study Guide 20 multiple choice 50 points 30 roots 30 points 1 essay question 40 points ID biology physics physiology chemistry 20 points Short answer 10 points Jake Sieger Composition Know what fits in categories of Vector Agent Environment Host Reservoir etc Multiple Choice Scientific Method question hypothesis experiment data results o Hypothesis a potential testable explanation for an observed o Theory an idea that has been tested with results that corroborate the o Law fixed observation that can be measured a theory gives reasoning phenomenon specific idea but can be disproved to a law Independent variable controlled variable measured with less variation Dependent variable not controlled usually greater variability Correlation vs Causation o Causation results in correlation o But correlation doesn t imply causation E O Wilson o Discovered that a death smell was present in ants that died o Oleic Acid Monounsaturated fat Found as a fatty acid of a triglyceride o Ants took living ants exposed to oleic acid to the graveyard Zoonotic Diseases diseases that travel from animals to humans o Transmission of an infectious agent as a result of direct or indirect contact with an infected animal o Zoonotic diseases are multifactorial and their occurrence is affected by interactions between the host the agent the vector and the environment o Agent Pathogen o Pathogen any disease causing agent o Zoonotic Pathogens Virus Bacteria Fungus Prion Robert Koch was a German scientist considered by many to be the founder of bacteriology o Koch s Postulates disease Pathogen must be isolated from animals that died of the Pathogen must be grown in pure culture identified Pathogen from pure culture induce the same disease when injected into healthy animals Pathogen must be re isolated re identified from the second animal and re grown in pure culture Mosquitoes o Order Diptera Family Culicidae Many Genus o 3 000 3 500 species on Earth 170 in US 60 in Ohio o Long proboscis o Long legs o Scales on wing veins o Antennae o Gonotrophic Cycle Need to feed on a blood meal to then lay eggs Female goes from non reproductive to mating to blood meal and then produces eggs o Life cycle Holometabolous four life stages Egg 3 types o Culex egg rafts 30 300 eggs Rafts to float on top of water Lay eggs where organic debris is present Can tell age by color o Aedes eggs little cigars Single eggs up to 400 Above water line Eggs can last years Lay eggs in containers and tree holes o Anopheles with floats Single eggs On water surface Prefer to lay in swamps Larva Obligate aquatic insects 4 14 days temperature dependent Air breathing siphon on posterior abdomen for breathing snorkel Filter feeders Not found in areas of high water movement waves Pupa Non feeding Aquatic obligate Air breathing different morphology than siphon same concept Adult Cannot fly right away and must expand and dry wings Some survive winter some survive as eggs or larva Males have different attenae than females Males also have Johnston s Organ below Hibernaculae hide in covering during winter season o Johnston s Organ o Mosquito mouthparts Collection of sensory cells found in the pedicel of the antennae Detects motion in the flagellum Mosquitoes have mouthparts which are used for piercing and sucking The paired mandibles and maxillae are formed into needle like structures stylets which are enclosed by the labium When a mosquito bites the pointed and barbed pair of maxillae penetrate the dermal tissue of the vertebrate to anchor the mouthparts in the tissue This also provides leverage when the other mouthparts are inserted The sheath like labium slides back and the remaining mouthparts pass through its tip and into the tissue The mosquito injects saliva which contains anticoagulants into the tissue to stop the blood from clotting The labrum acts like a tongue and is used to suck up the blood West Nile Virus o Pathogen RNA virus Flavivirus o Vector Mosquitoes Sylvanic Vector Culex spp Host Vector Many Many spp o Reservoir Birds o Incubation 2 14 21 days o Treatment Supportive o 332 positive bird species for WNV o Horses Vaccine Fatality Rate 40 o Zoonotic disease generally very rare before West Nile Expect 2 000 WNV cases a year o West Nile Fever West Nile Encephalitis 3 outcomes Pathogen exposure no illness 100 subclinical complete recovery 75 WNFever develops 25 WNEncephalitis develops 1 o 10 fatal o Latent effects as well o How does WNV get in blood stream Must infect at least two cells keratinocytes Must get into brain from blood to develop fever or encephalitis Needs a living cell to replicate Can stop spread of virus by stopping attachment to host cell Incorporates RNA into human genome Antigens match with a specific cell type with specific receptor o Viruses proteins o Modes of transmission Solid tissue transplantation Intrauterine infection Blood transfusion Breast feeding Percutaneous exposure occupational Mosquito bite o Difference between Aedes and Culex Culex lay eggs at above 8 10 feet Aedes lay eggs anywhere below that o Lab Testing Receiving sample processing Grinding RNA extraction 1 5 hrs I Cycler PCR 96 wells per plate 92 samples 4 controls 3 hr run time o Department of Health Kidney and brain highest concentrations of virus in birds test tissue from kidneys for WNV Mosquito identification under a microscope Test for WNV by species Tissue must be ground LaCrosse Encephalitis o Pathogen RNA virus Bunyavirus o Vector Mosquitoes Aedes triseriatus Sylvanic Vector Aedes triseriatus Host Vector Aedes triseriatus o Reservoir Chipmunks squirrels o Incubation 5 15 days o Most common in people under 16 o Mortality rate 1 o Treatment Supportive o Aedes triseriatus Eastern Tree Hole Mosquito Mammal feeder Aggressive biter Distinctive abdominal terminus Breeding sites Containers Tires Tree Holes o Transmission Cycle Can be passed down through eggs Sylvanic cycle in chipmunk Humans are dead end hosts o Occurs only in the eastern half of the US Ohio has had the most cases since the 60 s o Long term immunity conferred Does not always result in symptoms 80 cases a year in the US o Treatment NO vaccine NO antiviral meds available Supportive fluids anti seizure etc o Symptoms Fever Headache Nausea Fatigue Lethargy Neurologic o Testing PCR of LaCrosse Virus LACV in CSF PCR of LACV from tissue necropsy LACV specific IgM antibody in serum or CSF IgM in Acute Convalescent Phase Triple E EEE Eastern Equine Encephalitis o Pathogen RNA Virus