Microbiology Lab Exam #4

Card Set Information

Microbiology Lab Exam #4
2014-05-07 12:16:00

Microbiology Exam #4
Show Answers:

  1. Prevalence
    Total number of people in a population who have a disease at a particular time, regardless of when they caught it or when they were diagnosed

    (Total # of cases in the pop/Total # of people in the pop) * 100,000
  2. Incidence
    The number of new cases of disease that occur within a certain time period

    (# of new cases in the pop/# of people in the pop) * 100,000
  3. Epidemic
    A disease acquired by many in a given area in a short time
  4. Pandemic
    Worldwide epidemic
  5. Endemic
    A disease constantly present in a population
  6. Sporadic
    A disease that occurs occasionally in a population
  7. Blood Typing
    • A & A -> A
    • A & O -> A
    • B & B -> B
    • B & O -> B
    • A & B -> AB
    • O & O -> O
  8. Rh Factor
    • Rh+ & Rh+ -> Rh+
    • Rh+ & Rh- -> Rh+
    • Rh- & Rh- -> Rh-
  9. Erythroblastosis Fetalis
    When a Rh- mother is pregnant with an Rh+ baby.  At birth, when the placenta ruptures, the mother's RBC's recognize the baby's blood as foreign creating antibodies against Rh+ blood creating problems with future pregnancies in which the baby has Rh+ blood.
  10. WBC Types
    Granulocytes & Agranulocytes - depends on the absence or presence of stained granules in the cell's cytoplasm
  11. Types of Granulocytes
    Neutrophils - light purplish granules stained up by neutral dyes; primary phagocyte of the blood stream

    Basophils - granules attract basic dyes, which stain the granules dark purple; granules contain histamine & other chemicals involved in allergies

    Eosinophils - granules stained bright red or orange by eosin; purpose is uncertain but may be to engulf antigen-antibody complexes
  12. Types of Agranulocytes
    Lymphocytes - have a very large nucleus with little cytoplasm around it; B-cells & T-cells that are important in acquired, or specific, immunity

    Macrophages (monocytes when not mature) - large WBC's with a kidney shaped or C-shaped nucleus - dendritic cells present antigens to lymphocytes
  13. WBC Composition in Humans
    • Neutrophils - 60-70%
    • Lymphocytes - 20-25%
    • Monocytes - 1-6%
    • Eosinophils - 2-4%
    • Basophils - 0.5-1%
  14. Organelle Represented as Neutral Stained Granules in Neutrophils
    Lysosomes - necessary for the digestion of engulfed microorganisms
  15. Type of WBC that shows an increased percentage in people who suffer from allergies
  16. Plaque
    Glucan & the community of microorganism attached to it
  17. Caries
    • AKA Cavities
    • Formed when saliva forms a coating on the tooth and bacteria that are attached to it use sucrose to produce fructose & glucan which in turn is fermented to produce lactic acid which can buildup and dissolve the calcium of the tooth
  18. Snyder Test
    Microbiological method for determining susceptibility to dental caries; measures the amount of acid produced by normal flora microorganism in a medium containing sugar; production of acid causes the color of Snyder agar to change from green to yellow
  19. Serological Tests
    Based on antibody/antigen reactions; can be direct or indirect
  20. Direct Serological Tests
    Use a known antibody from the lab to directly identify an unknown antigen (microbe) from the patient
  21. Indirect Serological Tests
    Diagnose disease by an indirect route; rather than taking the actual microbe from the patient, these tests check to see what antibodies the patient is producing - serum from the patient is mixed with an antigen from the lab; if a reaction occurs the patient has the specific antibody for that disease
  22. Heterophile Antibodies
    Non-specific antibodies that will react with other antigens besides the microbe causing the disease
  23. Heterophile Antigens
    Lab antigens that heterophile antibodies react with
  24. Reagin
    Heterophile antibodies produced by Syphilis patients; cross-reacts with other antigens besides Treponema pallidum
  25. Cardiolipin
    One of the reagin's used in the RPR test for Syphilis patients; when the antibodies attach to the cardiolipin antigens, the particles are clumped together as visible, black aggregates but if the patient does not have antibodies for Syphilis there will be no clumping
  26. Indirect ELISA Test (HIV)
    • 1.  HIV p24 antigens are manufactured & attached to the bottom of a plastic testing dish.
    • 2.  The dish is then washed with the blood sample.  If antibodies for the p24 antigen are present then they attach to the antigens in the dish.  This gives an HIV+ result.  If no antibodies are present & only antigens remain then it's a negative result.
    • 3.  The dish is washed with a second marker antibody.
    • 4.  The dish is then washed with a dye where the second marker antibody is present, the marker will cause the liquid in the dish to change color indicating a positive result.  If the liquid doesn't change color, then it's a negative result.
  27. Complement Fixation Test
    A diagnostic test for the presence of a particular antibody in the serum of a patient that involves inactivation of the complement in the serum, addition of measured amounts of the antigen for which the antibody is specific & of foreign complement, & detection of the presence or absence of complement fixation by the addition of a suitable indicator system - compare
  28. Types Of Animal Parasites
    Protozoa - single-celled eukaryotic organisms like AmoebaParamecium; some found in blood such as Plasmodium (cause of Malaria) and Trypanosoma (cause of African Sleeping Sickness & Chaga's Disease)

    Helminths (worms) - Nematodes (roundworms), Cestodes (tapeworms), & Trematodes (flukes); the larval stages can pose a serious medical threat by migrating & encysting in various organs of the body; majority of that infect humans tend to inhabit the intestinal tract and can be diagnosed by searching for eggs in fecal smear

  29. Protozoans
    • One celled organisms
    • 2 stages in their life cycle = trophozoites (motile, eating stage) & cysts (dormant, resistant stage; not all form cysts)
    • Categorized by their means of locomotion = spore formers, flagella, ammoeboid movement (pseudopods)
  30. Plasmodium
    • Causes Malaria
    • Reproduces inside of RBCs in the host
    • Transmission typically involves an arthropod vector, typically the bite of an Anopheles mosquito
    • Sporozoites can also be transmitted through contaminated blood and rarely through child birth
  31. Stages of Plasmodium Life Cycle
    • Sporozoites (the infective stage) travel to and replicate in liver cells
    • Merozoites are then released into the blood and travel to the RBCs where they feed on hemoglobin and reproduce asexually
    • The RBCs lyse at regular intervals (every 24 hours) releasing the merozoites into the blood stream - this causes fever
    • Some merozoites develop into male or female gametocytes and are ingested by mosquitos during feeding on the host
  32. Plasmodium
    • Causes Malaria
    • Blood samples collected to diagnose Malaria
    • Anopheles mosquitos are the method of transmission for Malaria
  33. Trichomoniasis
    • Urogenital disease transmitted through sexual contact (#1 STI)
    • Both males and females can contract - 70% of people infected but have no symptoms
    • Symptoms = itching, burning, and foul green-yellow discharge
    • Research has linked it with cervical and prostate cancer
  34. Trichomoniasis
    • Uses flagella as its method of movement
    • Swabs of the urogenital tract would contain the parasite
    • Sexual contact is the most common way to contract
  35. Giardiasis
    • Leading cause of water born infection
    • Parasite infects the small intestine in humans
    • Campers drinking unfiltered water are a high risk group
    • Multiple flagella found on the end of the organism is the method of movement
    • Most common method of detection = cysts/trophozoites in fecal smears (string test) and immunoassay or PCR for subtypes
  36. Entamaeoba histolytica
    • "Gut amoeba which dissolves tissue"
    • Amoebic dysentery
    • Most common in tropical regions of the world
    • Small intestines get damaged by this parasite
    • Moves by pseudopods
    • Transmitted fecally/orally
  37. Trichinellosis
    • Commonly associated with pork and bear
    • Larvae encyst within a muscle cell
    • Larvae are not killed unless the meat is cooked to the proper temperature
    • The cysts enter the digestive system and digestion releases the larva causing intestinal pain; adults mate and produce more larva
    • The larva can then travel throughout the body causing damage to multiple types of tissues
  38. Trichinellosis
    • Contaminates include pork, bear meat, other wild game that might eat garbage
    • Larva of the helminth migrate to other tissues
    • Can be diagnosed through blood test or muscle biopsy (look for encysted larvae)
  39. Enterobiasis (pin worms)
    • Adults live in small intestine
    • Female worm lays eggs at night around anal opening
    • Main symptom = anal itching but some complain of abdominal pain and trouble sleeping
    • Diagnosis = scotch tape test
    • Treatment = medication to kill adult worms and good hygiene practices to prevent spread (wash linens, clothes, hands, etc)
  40. Enterobiasis
    • Young children are most commonly infected
    • Classic method of diagnosis = scotch tape test
    • Advice for infected = after beginning treatment, wash all linens in hot water and ensure treatment of the whole family
  41. Schistosomes
    • S. mansoni and S. japonicum = mesenteric veins around gut/liver - eggs passed in feces, leads to hepatosplenomegaly
    • S. hematobium = bladder - eggs passed in urine, sometimes with blood
    • Can lead to stunted growth and trouble learning in children
  42. Schistosomiasis
    • This helminth lives in snails when not in humans
    • Larvae mature in the portal veins of liver then mate and migrate to veins around the gut or bladder depending on species
    • Feces and urine are used to diagnose schistosomiasis
  43. Taenia (tapeworms)
    • Pigs and cows ingest eggs from soil
    • Larvae encyst in muscle
    • Humans infected when eating undercooked meat
    • Adults live in small intestine and proglottides containing eggs are passed in feces
    • Scolex = head with suckers that attach to wall of small intestine
    • Rest of body = proglottids or segments containing male and female sex organs; monoeicious)
  44. Taenia
    • Taenia solium = pork tapeworm
    • Taenia saginatus = beef tapeworm
    • Food sources that contain tapeworms = pork, beef, and fish
    • Suckers and hooks of adult tapeworms typically attach to the small intestinal wall
    • Larva can encyst in other parts of the body including the brain and when killed can lead to inflammation (encephalitis)
  45. In order to determine blood type, what type of reaction must occur?
  46. The cells with multilobed nuclei that are the most prevalent in the blood are called
  47. The cells with reddish granules that are important for allergies and parasitic infections are called
  48. The cells that are almost all nucleus and are responsible for adaptive immunity are called