Micro Biology Unit 1 PCC – Flashcards
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Unlock answersProtozoa, # of species |
30,000 + |
Cycsts |
Formed by protozoa under adverse conditions. Round or oval protective coating. Allows survival until conditions improve. Latent form. |
Naegleria spp, Naegleria fowleri |
"Brain Eating Amoeba" Water containing the amoeba get high into the nose, bind to olfactory nerve gaining access to the brain. Risk factors: swimming, diving, splashing in warm bodies of standing water. |
Acanthamoeba |
Unresolved may lead to chronic granulomatous encephalitis (inflamation of the brain). Corneal ulceration leading to blindness may also occur |
Entamoeba hisolytica |
Pathogenic Highest rates in areas of crowding and poor sanitation 10% of worlds population Perforation of amoebic ulcers facilitate invasion of deeper tissue Abscess formation may occur Fecal oral |
Trophozoites |
Active form of protozoa. Not in cyst form. |
Asymptomatic carriage |
Host carries the organism, but with no symptoms; can spread to others. |
Tichomonas vaginalis |
Urogenital flagellate Trophozoite stage only Infection by sexual intercourse or fomites Sympromatic women: scant watery discharge, painful urination Symptomatic men: urethritis and prostatitis |
Fomite: |
inanimate object that spreads disease |
Giardia lamblia
|
Most common pathogen in US drinking water. Intestinal flagellates Has a "looking back" apearance Cyst is resistant to standard chlorine concentrations, can be removed through filtration. |
Giardiasis |
Cause: Giardia lamblia AKA Bever Fever Diarrhea, flatulence, abdominal pains, fatty stools |
amastigote |
tiny form of trypanosome, becomes bigger in the body |
Trypanosoma brucei gambiense |
Classic African Sleeping Sickness Transmitted by the tsetse fly |
Classic African Sleeping Sickness |
Caused by Trypanasoma brucei gambiense asymptomatic incubation period lasting a few weeks to several months. Neurological stage 7-8 year process. |
Trypanosoma brucei rhodesiense |
more virulent form of trypanosomiasis Vector: teste fly Untreated death within 9-12 months
|
Trypanosoma cruzi |
causes chaga's disease (American trypanosomiasis) Transmited by the reduviid (kissing)bug Resevoir: wild rodents, armadillos Causes IgM levels to rise Cardiac muscle where amastigotes proliferat atrophy |
Leishmania spp. |
Transmitted by the sand fly |
Plasmodium vivax |
most common malarial parasite Invades reticulocytes (young RBC's)
|
Plasmodium ovale |
Also attacks reticulocytes. |
Plasmodium malariae |
Much lower incidence Attacks mature RBC's |
Sporazoit |
infectious form of malaria from a mosquito |
Plasmodium falciparum |
worst form of malaria Targets all stages of RBC's Causes blood in the urine, gives severe malaria the name blackwater fever. |
Toxoplasma gondii |
Up to 80% of individuals in some populations carry the disease. estimated 1/3 of the world population Definitive host is the domestic cat 3 days for oocysts to mature Infection results from ingestion of oocysts Sex cycle occurs only in feline intestinal tract Infection usually occurs after contact with litter/sand box, gardening, playing with cat poo Immune system encysts the paracite, typically do not reemerge
|
IgE |
serum IgE levels rise during parasitic infection. useful in diagnosing infection. |
Trematodes |
Flukes Flat, fleshy, leaf shaped body Hermaphroditic (except for Shistosomes) |
Opisthorchis sinensis |
Liver Fluke Infection from ingestion of raw/undercooked fish. Resevoirs: Raw fish-eating mammals |
Fasciolopsis buski |
Giant intestinal fluke Resevoir hosts: pigs, dogs, rabits |
metacercariae |
infective encysted larval stage of fluke |
Paragonimus westermani |
Lung fluke Eggs are discharged into the bronchi or bronchioles, later apearing in feces or sputum Often misdiagnosed as TB |
Schistosomes |
Blood Flukes Non hermaphroditic Infection does not result from ingestion |
Shistosoma haematobium |
Eggs deposited in bladder wall, may break through into the lumen and escape with the urine. Feared as male menstruation |
Non-human pathogenic schistosomes |
Schistosomal dermatitis AKA swimmers itch |
Cestodes |
Tapeworms hermaphroditic |
Scolex |
attachment organ of a tapeworm. If it remains the worm will regrow |
Proglottids |
body segments of a tapeworm, a chain of proglottids is called a strobila |
Taenia solium |
Pork tapeworm Aquired by ingestin the larval form (cysticercus AKA bladder worm) There may be a second stage of infection. |
Cysticercosis |
socond stage of infection by pork tapeworm. Ingested eggs travel to duodenum where they hatch and penetrate the intestinal wall. |
Taenia saginata |
Beef tapeworm |
Exhinococcus granulosus |
The minute tapeworm Causes hydatid disease Found in sheep |
Hymenolepsis nana |
Dwarf tapeworm common parasite of house mouse Can be found in grains. Eggs from adult worm may hatch in hosts intestine and cause second generation infection. |
Diphyllobothrium latum |
broad fish tapeworm longest human tapeworm Causes normochromatic macrocytic anemia due to absorption of B12 |
Nematodes |
Phylum: Aschelminthes Roundworms covered by tough protective covering (cuticle) Have complete digestive tract sexes are seperate |
Ascaris lumbricoides |
Large intestinal round worm Found in areas of poor sanitation Eggs are ingested Larva penetrate wall of duodenum, enter blood or lymphatic vessels. grow and molt in lungs. mature in intestines. |
Enterobius vermicularis |
Pin worm Most common helminth in sanitary areas No symptoms in carriers Female explodes outside anus releasing eggs and causing itch. |
Amoebiasis |
Caused by Entamoeba histolitica Most cosmopolotan parasitic diseas |
Intestinal amoebiasis
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Caused by Entamoeba histolytica AKA amoebic dysentery bloody, slimy, and unusually smelly diarrhea |
Extraintestinal amoebiasis |
Caused by Entamoeba histolytica Infection of the liver is common |
Trypanosomes |
Hemoflagellates live in the blood, between cells but not in them |
Winterbottom's sign |
Characteristic of Gambian "classic" Sleeping sickness Swelling of the posterior cervical lymph nodes |
Toxoplasmosis |
Toxo Caused by toxoplasma gondii Fetus is particularly susceptible especially during third trimester. Symptoms for neonatal: convulsions, retardation
|
Miracidium |
Trematode larva Typically infect snails |
Strongyloides stercoralis |
Threadworm can exist as a free-living nematode larva penetrate the skin, migrate through the lungs, and reach small intestine. "showers of worms" in feces Auto infection-multiple life cycles in host |
Filariform |
infectious;hookworm larva |
Rhabditiform |
non-infectious nematode larva |
Hookworms |
Two species are human pathogens No intermediates or resevoir hosts |
Ancylostoma duodenale |
Old World Hookworm larva enter cutaneous venules, passively carried to lungs, break into alveoli. Migrate to trachea and are swallowed Induce Microcytic Hypochromic Anemia suck blood and tissue fluids |
Necator americanus |
New World Hookworm only hookworm in N. America produces "ground itch" where entering skin |
Ancylostoma braziliense or caninum |
Dog hookworms Will penetrate skin and cause itching. Survive weeks just below surface, then die. |
Trichuris tichiura |
Whip worm |
Trichinella spiralis |
live births parisite of carniverous mammals Larva encyst in muscle tissue |
Filariae |
Live births thread like nematodes live in various locations Not diagnosed by eggs in feces (live birth) |
Wuchereria bancrofti |
a filiariae Spread by mosquitoes Mature in lymph nodes produce microfilariae dead worms cause alergic reactions Causes Filariasis |
Filariasis |
caused by wuchereria bancrofti Febrile attacks reffered to as elephantoid fever Lymphangitis and Elephantiasis-does not occur in all infested individuals |
Loa Loa |
African eye worm Resevoir: Monkeys Vector: Mango fly no lasting damage to host |
Onchocerco volvulus |
causes River Blindness Vector: Black fly or Buffalo gnat |
Dracunculus medinensis |
the Guinea Worm Not a true filaria Ingestion of larva in water females migrate to subcutaneous tissue |