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Micro Ex4

Pathogens parasites that cause diseases
ectoparasites live on the surface of other organisms
endoparasites live within the body of other organisms
obligate parasites spend at least some of their life cycle in or on a host
facultative parasite normally free-living but can obtain nutrients from a host
permanent parasites remain in their host once they have invaded (tapeworm)
temporary parasites feed on and leave their host (biting insects)
accidental parasites invade other than their normal host (ticks attach to dogs, occassionally attach to humans)
symbionts organisms live together in which the association is of mutual advantage
mutualism both partners benefit
commensalism one partner benefits and the other is unharmed
parasitism one organism (parasite) derives benefit at the expense of the other (host)
vector any living organism that can carry disease-causing microbe from one host to another
What are the two types of vectors? biological in which the parasite go through part of its life cycle within the host and mechanical in which an organism moves contaminated material from one location to another
Differentiate between the different types of hosts. definitive harbors the sexually reproducing stage of the parasite; intermediate is where parasite undergoes asexual reproduction; reservoir is the source of the disease-causing organism
encystment formation of an outer covering that protects from unfavorable factors
T/F Parasites can change surface antigens faster than host can make antibodies. True
What types of damage can parasites cause to their host? rob nutirents, trauma to tissue cells, clot/damage blood and lymphatics, internal hemprrhage, severe inflammatory response
What is unique about algae? contain chlorophyll, unicellular/multicellular, contain holdfast structure that serves to anchor the organism, produce toxins
How do algae divide? asexual through binary fission, mitosis, or fragmentation. sexually through meiosis
How are algae classified and what are these groups? based on photosynthetic pigments; red algae (seaweed) and brown algae (kelp)
Part of the Pyrrophyta group that produce red tides Dinoflagellate
What are the two types of dinoflagellates? toxins produced? Which is more serious? Gymnodinium (breve toxin) and Gonyaulax (neurotoxin - more serious)
Which type of dinoflagellate produces a tingling sensation of mouth and fingers? Gymnodinium breve
Which type of dinoflagellate can result in respiratory failure and death? Gonyaulax
What is unique about protozoa? unicellular, motile during at least one stage in their development, feed by either phagocytosis or pinocytosis, polymorphic, can exist as trophozoite (vegetative) or cyst (resting)
What is the habitat of algae? found in fresh and salt water as well as soil
What is the habitat of protozoa? complex life cycles involving more than one habitat; free-living in marine and fresh water as well as terrestial environments
How do protozoa divide? often by binary fission but some by multiple fission or schizogony
schizogony nucleus divide a number of times before individual daughter cells are produced
How are protozoa classified and what are the groups? based on locomotion; sarcomasigophora (flagella), apicomplexa (non-motile), ciliophora (cilia), microsporidia (obligate intracellular)
Differentiate between the two groups in Sarcomasigophora. Mastigophora are flagellate protozoa and Sarcodina move by means of pseudopod amoeboid movement
What is the vector for the protozoa also called "Kala-azar?" Leishmania from Sandfly
What happens in systemic or visceral leishmaniasis? most sever type where parasite infects immune cell macrophages that in turn carry it to the spleen, liver, and bone marrow
What is the most common form of mastigophora infection in the US? What is unique to this? Giardiasis found in contaminated mountain streams and resistant to chlorine in cyst stage; causes acute or chronic diarrhea, severe malabsorption syndrome, bulky stool
What is the mastigophora infection that causes pruritis, malodorus, frothy, yellow-green discharge? reservoir? trichomoniasis; men are asymptomatic reservoirs
What is unique to the Hemoflagellates? found in blood or lymph, long slender body, transmitted by bites or feces of blood-feeding insects
What causes African sleeping sickness? unique symptoms? Trypanosoma brucei (tsetse fly); enlarged lymph node, gradual loss of interest, coma, then death
What causes Chagas disease? Trypanosoma cruzi
What is the kissing bug-insect vector? How is it transmitted? Reduviridae; pierces the lips, eyelids, or ears of a sleeping human victim
What are some diseases caused by Entamoeba histolytica? amoebic dysentery, hepatic amoebiasis, acute peritonitis (GIT)
How is Naegleria fowleri transmitted? swimming or diving; trophozoites penetrate nasal mucosa and ascend along olfactory nerves to invade brain tissue
What are some diseases caused by Naegleria fowleri? purulent meningitis, encephalitis, and primary amoebic meningoencephallitis (when cytotoxic enzymes destroy blood-brain barrier)
How do Apicomplexa get into the host cell? non-motile, produce enzymes located in organelles at the apices which helps to digest their way into host cells
What forms of malaria cause fever every other day? P. falciparum (malignant tertian), P. vivax (benign tertian), P. ovale (ovale tertian)
What type of malaria causes fever every third day or 72 hours? P. malariae (quartan)
What is unique about Toxoplasma gondii? can cross placenta resulting in neurological damage to fetus, results from contact with domesticated cats, asymptomatic in most humans but severe in immunocompromised
What is unique about Cryptosporidium parvum? host can be dogs, pigs, or cattle; produce profuse and watery diarrhea; contaminated food or water
What are the two members of Ciliophora? Which can cause human disease? Paramecium and Balantidium colu which can cause ulcers in large intestines from pig host
What is unique about Microsporidia? invade every organ of the body, found in marine habitats, parasitic on fish and other sea life, obligate intracellular
What is the optimal environment for fungi? high concentrations of salt, sugar, and amino acids; moist envrironments; 20-35*C and pH of 5.0 or lower
saprophytes digest dead organic matter and wastes
How are fungi classified? reproduction and morphology
zygomycota bread mold (Rhozopus)
ascomycota causes Dutch elm disease and rye smut (soot)
basidiomycota mushrooms and puffballs
deuteromycota imperfect fungi, no sexual stage, penicillin
chytridiomycota Black wart disease of potato (motile)
What is the morphology classification of fungi? yeast (single celled, spherical or oval); molds (multicellular, filamentous); diamorphic (yeast or mold depending on environment)
mycelium collection of hyphae growing in one place
hypha single filament of molds that absorb nutrients and releases enzymes which break down material into readily absorbed smaller organic compounds
What is the common fungi in human diseases? what is an example of this? diamorphic; Coccidiodes immitis is grown in soil as mold, spores carried in air and inhaled by humans, develop into yeast and cause disease
How can hay fever or asthma be caused by fungi? by inhaling spores
How are fungi used in child birth? other uses? purified form of rye smut called ergot used to control uterine bleeding; also relieve migraine headaches
How can fungi be cancerous? some aspergillus species produce aflatoxin found on moldy foods such as grains or peanuts which has been linked to liver cancer
What causes Spelunker's disease? Histoplasma capsulatum
What are two infections of Candidiasis? unique symptoms? Oral thrush with cracks in corners of mouth and whitish or yellowish patches; Vulvovaginitis with painful urination and thick, white, cheesy discharge
Classify fungi by the body parts infected. superficial mycoses (hair, skin, or nails), intermediate (respiratory, skin or subcutaneous tissues), systemic (tissues deep within the body)
What are the positive impacts of fungi? Sacchromyces used in beer, wine, and bread production; penicillin and antimicrobial medicines; genetic and biochemical studies
What are the negative impacts of fungi? food spoilage, cause plant diseases (Dutch elm and wheat rust)
What are some diseases caused by mosquitoes? fleas? lice? malaria; plague; trench fever, epidemic typhus, relapsing fever
What are some diseases caused by ticks? mites? dust mites? rocky mountain spotted fever and lyme disease; scabies; allergies and asthma
What is unique about Helminths? worms and flukes, multicellular, life cycles involve intermediate hosts for larval development and definitive host for adult form, hermaphrodite
What are the roundworms? flatworms? Nematodes; Trematodes and Cestodes
What is the host, location, and transmission of Enterobius vermicularis? humans; large intestine; close contact or autoinfection
What is the disease caused by Enterobius vermicularis? unique symptoms? Enetrobiasis; insomnia, perianal and vulvar pruritis, irritability
What is the host, location, and transmission of Trichinella spiralis? rats, pigs, and man; muscles (larvae) and small intestine (adult); consumption of meat containing larvae
What are the unique symptoms of Trichinosis? myalgia and eosinophilia, myocarditis or encephalitis in extreme infection
What is the host, location, and transmission of Necator americanus or Ancylostoma duodenale? human; small intestine; fecal pollution of soil with larvae (walking barefoot)
What are unique symptoms of hookworm infection? dermatitis, pulmonary migration of larvae to produce blood tinge sputum, intestinal infection produces iron deficiency anemia
What is the host, location, transmission of Strongyloides? humans; general tissue (larvae) and small intestine (adult); skin penetration or autoinfection
What are the unique symptoms of thread worm infection? Strongylodiasis; pruritis, weight loss, bronchopneumonia in severe cases
What is the host, location, and transmission of Ascaris? human; small intestine; ingestion of eggs
What are the unique symptoms of Ascariasis? abdominal pain with live worms vomited or passed in stool, pneumotitis and intestinal obstruction with heavy infestations
What is the host, location, and transmission of Wuchereria bancrofti? humans and mosquitoes; blood (larvae) and intestines (adult); mosquito bite
What are the unique symptoms of Wuchereria infection? Filariasis; swelling of lymph glands, genital, and extremities
What is the host, location, transmission, and disease caused by Trichuris? humans; large intestine; ingestion of eggs (no animal reservoir); Trichuriasis (whipworm) which is mostly silent but can cause flatulence and tenesmus
What are the similarities of the Schistosoma species? blood flukes with snails and human host and penetration of skin by larvae released from snails
Which trematodes infect the blood vessels of the intestine? symptoms? S. japonicum and S. mansoni; malnutrition, liver damage, ascites (belly fluid), eosinophilia
What trematode infects the blood vessels of the bladder? symptoms? S. haematobium; hematuria, urinary frequency, urethral and bladder pain
What is the host, location, transmission, and symptoms of Fasciola infection? humans, snails, fish, sheep/cattle; liver; ingesting vegetation with larvae; epigastric pain, anorexia, jaundice, enlarged liver
What disease is caused by Taenia saginata? symptoms? Beef tapeworm; obstruction of bile duct, pancreatic duct, or appendix
What is the disease caused by Taenia solium? Pork tapeworm; obstruction of bile duct, pancreatic duct, or appendix
What disease is caused by Diphyllobothrium latum? symptoms? Fish tapeworm; Vit B12 deficiency, macrocytic megaloblastic anemia (pernicious anemia), numbness, loss of vibration sense, unsteady gait
What disease is caused by Echinococcus granulosus? symptoms? Dog tapeworm and Hydatid disease; liver cyst, upper right quadrant pain, anaphylaxis with cyst rupture
What is different about the dog tapeworm? While others occur in intestine, dog tapeworm occurs is liver, lung, and brain
What is the most common cause of cestode infection in the US? Beef tapeworm
What are general characteristics of viruses? non-living infectious agents, obligate intracellular, no true cell, small size measured in nm
What can viruses infect? animals, plants, other microorganisms, bacteria (bacteriophage)
What is the criteria used to define a virus? contain one type of nucleic acid (DNA/RNA), totally dependent on host for replication, viral components assembled into virions to go from one host cell to another
isometric nucelic acid surrounded by a polyhedral (adenovirus)
helical ribbon-like consisting of nucleic acid surrounded by a hollow protein cylinder or capsid and possessing a helical structure (tobacco mosaic virus)
complex polyhedral head and helical sheath or tail (most phages)
naked virus protein capsid/nucleic acid; can survive in the outside world
enveloped virus capsid/nucleic acid/envelope; susceptible to drying, gastric acidity, bile, etc
What are the structures of the capsid? made of protein capsomeres, protects and introduces viral genome into host, attachment proteins bind virus to host
What are the structures of the envelope? derived from host cell membrane by budding, virus incorporates proteins of its own (glycoprotein spikes) which attach virus to host
Are the viral enzymes active? inactive but becomes active after virus has entered the host
Where does viral replication occur? DNA is in the nucleus, RNA in the cytoplasm
How are viruses transmitted? inhaled droplets, food or water, direct transfer, bites or vector arthropods, transplacental, sexually
What is the interaction that determines specificity of the virus? specific interaction between the nucleocapsid of virus and host molecules
virulent phage multiply inside the host cell and cause lysis phage and productive infection
temperate phage becomes part of the genome of the host cell and modifies properties of the host cell
lysogenic cell bacterial cell carrying prophage to produce latent infection
extrude virus can leak out of the host cell without killing them
Describe the first stage of viral replication. attachment: virus must bind to a receptor on the host cell
What occurs after viral attachment during replication? an enzyme in the tip of the phage tail degrades a small portion of the bacterial cell wall and the DNA is injected into host while protein coat remains outside
What occurs during transcription in viral replication? phage DNA in the host cell is transcribed into mRNA which is then translated into protein
What occurs during replication and synthesis of the virus? phage protein and nucleic acid replicate independently; DNA serves as template for replication of more phage and template for synthesis of mRNA
What occurs during assembly of the virus? once the phage head is formed, it is packed with DNA and the tail is then attached following the addition of tail spikes
What occurs in the last step of viral replication? enxyme lysozyme is synthesized and digest host cell from within resulting in cell lysis and release of phage
generalized transduction any bacterial gene transferred; DNA from donor cell integrate into recipient cell by homologous recombination
specialized transduction only transfer specific genes; a piece of bacterial DNA remains attached to temperate phage DNA that is excised and replicates as phage replicates; only genes near DNA that pahge integrates are transduced
cytopathic effect virus is propagated in tissue culture and often changes the cell's appearance
What is the cytopathic effect in Hep B? ground glass appearance in liver cells
Describe the acute infection seen in animal viruses. short duration, self-limited, localized virus, leads to lasting immunity
Describe the persistent infection seen in animal viruses. late complication following acute infection, latent, chronic, and slow infection
What are the stages of animal virus replication? attachment, entry, targeting to site of replication, uncoating, replication of nucleic acid/protein, maturation, release, shedding, transmission
How are animal viruses released? cell lysed, budding, exocytosis
In which step does protein formation occur in animal viruses? maturation
T/F In all viruses nucleic acid separates from its protein prior to start of replication True
How are animal viruses shedded from their host? Shedding occurs from the same opening or surface that virus enters from
segmented virus exchange of genome to infect same cell by two viruses with different host range (influenza pandemics)
teratogen a drug or agent that induces defects during embryogenic development
leads to lymphadenopathy, failure to thrive, or encephalopathy within 2 years of birth HIV
acquired during passage through an infected birth canal HSV
What is the usual infection and how can cancers result from Epstein-Barr virus? herpesvirus (mono); Burkitt's lymphoma, Hodgkin's lymphoma
T/F HPV cause cervical cancer. False only HPV-16 and HPV-18 are associated
What type of cancer is caused by HepB and HepC virus? hepatocellular carcinoma
What virus can cause Kaposi's sarcoma? HPV-8
What are the double-starnded DNA viral families? Adenoviridae, Hepadnaviridae, Herpesviridae, Papillomaviridae, Polyomaviridae, Poxviridae
What is the #1 cause of common cold? #2? #3? 1=rhinovirus, 2=coronavirus, 3=adenovirus
Which virus causes cirrhosis or chronic hepatitis? transmitted? Hep B (enveloped); body fluids, blood, perinatal
Which viruses can cross the placenta? Toxoplasmosis, Others, Rubella, Cytomegalovirus, Herpes Simplex (TORCH)
Which virus causes chicken pox? HHV-3, Varicella-zoster
Which virus causes cold sores? HHV-1
Which DNA viruses can be transmitted through respiratory route? HHV-3, Adenovirus, HHV-6 (Roseola), Polyomavirus, Orthopoxvirus, Human parvovirus B19
Which virus causes owl-eyed shaped cells and congenital cytomegalic inclusion disease? Cytomegalovirus (HHV-5)
Which virus causes infantile exanthem subitum (6th disease)? Roseola virus (HHV-6)
What are the diseases caused by HPV? wart on skin/genitals, condyloma acuminatum, cervical/penile cancer
Which form of Polyomavirus causes leukoencephalopathy? kidney disease? JC; BK
Which virus causes smallpox? Orthopoxvirus
Which virus causes a nodular wart like skin lesion common on the trunk, genitalia, and proximal extremities? Molluscipoxvirus
Which virus causes erythma infectiosum (5th disease)? Human parovirus B19
malignant tumor of B lymphocytes Burkitt's lymphoma
infection of young causing fever, malaise, and "slap cheek" appearance in late winter/spring erythma infectiosum (5th disease)
What viral families contain arboviruses? Bunyaviridae, Flaviviridae, and Togaviridae
causes Hantavirus pulmonary syndrome. vector? Sin Nombre-like viruses; rodents
Ebola virus Filovirus
What are characteristics of Influenza virus? segmented genome, antigens hemagglutinin and neuraminidase, antigenic shift/drift
What causes Rubeola measles? symptoms? Morbillivirus (enveloped); maculopapular rash, Koplik's spots
What is SSPP disease and what causes it? subacute sclerosing panencepalitis; slowly progressive degeneration of brain; Morbillivirus
What disease is characterized by a barking seal sound and what causes it? Laryngotracheobronchitis (croup); Paramyxovirus
What causes Parainfluenza virus 1-4? Paramyxovirus
What is the common cause of fatal acute respiratory tract infection and what causes it? Respiratory syncytial virus (RSV); Paramyxovirus
What causes Rabies? unique symptoms? Lyssavirus (enveloped); hydrophobia, lethargy, Negri bodies intracytoplasmic inclusions
What viruses are transmitted by Aedes? Yellow fever virus, Dengue virus, Venezuelan equine encephalitis
What viruses are transmitted by Culex? West Nile virus, Japanese encephalitis virus, Venezuelan equine virus
Which Flavoviridae virus causes severe encephalitis? Venezuelan equine encephalitis
What is the target of Enteroviruses and when are they common? motor neurons; summertime (pools)
What are the stages of Polio infection? asymptomatic, minor polio, aseptic meningitis, paralytic (major) polio
vasicular ulcerated lesion around soft palate Coxsackie A Herpaginia
lesion on oral cavity then on palm and soles Hand-foot-mouth disease
atrophy of muscles, pain in chest Coxsackie B myocarditis, pericarditis, pleurodynia
causes infectious hepatitis Hep A virus
What causes AIDS and how does it work? Lentivirus; highly variable and infects CD4 T cells and macrophages
What viral family causes leukemia and tumors? Retroviridae; Oncoviruses
What diseases are caused by Alphaviruses? Eastern/Western equine encephalitis
What causes German measles and what population is this common in? what is the effect? Rubivirus; pregnant women in 20th week; cataract, deaf, mentally retarded
Which form of Hepatitis has a high mortality rate in pregnant women? Hep E virus
What causes gastroenteritis on cruise ships? Norovirus (Norwalk virus)
What causes SARS? Coronavirus (enveloped)
What are the diseases caused by Rotaviruses? Gastroenteritis, Respiratory infection, Acute infection in infants
How is HIV transmitted? blood, semen, vaginal secretion, intrauterine, peripartum, breast milk
Created by: jtnguyen