Protozoa

Question 1

Protozoa
Characteristics

Answer 1

-Domaine:Eukaryotic; Kingdom:Protista;Unicellular
-Inhabit water or soil; 1 or 2 nuclei
-Vegetative form (feeding&growing) is a Trophozoite
-Asexual reproduction by fission, budding
-Sexual reproduction by conjugation

Question 2

Phylum

Answer 2

*Sarcomastigophora
*Ciliophora
*Apicomplexa

Question 3

Sarcomastigophora
-Sarcodina (amoeboids)

Answer 3

-Move and feed by cytoplasmic projections called pseudopods
*Entamoeba histolytica
-Carried by 10% of the population (50% Mexican)
*Acanthamoeba
-Thicker walls than Entamoeba
-Source: stagnant water
-Causes Keratitis
*Naegleria (brain eating amoeba)
-PAM (primary amoeba meningoencephalitis)
-Indication: pain in front of head

Question 4

Sarcomastigophora
-Mastigophora (flagellates)
-Blood and tissue Flagellates

Answer 4

*Leishmania tropica
*Trypanosoma cruzi
-Causes sleeping sickness, rash, adema
-Grows in gut of Reduiid bug (kissing bug)

Question 5

Sarcomastigophora
-Mastigophora (flagellates)
-Digestive tract and genital tissue Flagellates

Answer 5

*Giardia lamblia
-Causes Giardiasis, multinucleated. -10-20 cysts infect, colonizes & reproduces in the small intestine
*Trichomonas vaginalis
-Women are more sensitive (16-35 years old) 5million cases/year
-Acidic pH helps prevent infection
-Causes preterm delivery, low birth weight, predisposing to HIV & cervical cancer

Question 6

Ciliophora

Answer 6

-Ciliates: move by cilia that are similar to but shorter than flagella
*Balantidium coli
(Only human parasite of this class)

Question 7

Apicomplexa

Answer 7

*Nonmotile
-Obligate intercellular parasites, anchor to host cell, complex life cycle

Question 8

Apicomplexa
-Sporozoa

Answer 8

*Plasmodium falciparum
*P. malariae
*P. vivax
*P. ovale
-feed on hemoglobin in RBCs
-falciparum causes most infections
-humans are secondary host

Question 9

Plasmodium
Life cycle

Answer 9

1.infected mosquito bites human (sporozoites migrate through bloodstream to liver)
2.sporozoites undergo schizogony in liver cell. Merozoites are produced
3.merozoites released into bloodstream from liver may infect new RBCs
4.merozoite develop into RING STAGE in RBC
5.RING STAGE grow and divide producing Merozoites
6.merozoites are released when RBC ruptures. Some infect new RBCs, some develop into male and female gameotocytes
7. Another mosquito bites infected human and ingests gametocytes
8.in mosquito digestive tract, gametocytes unite to form zygote
9.resulting sporozoites migrate to salivary glands of mosquito

Question 10

Apicomplexa
-Coccidia

Answer 10

*Toxoplasma gondii (cat litter)
*Cyclospora (causes watery diarrhea)
*Babesia (vector-tick, malaria like)
*Cryptosporidium spp. (causes respiratory & glass bladder infection in immunosuppressed people)

Question 11

Antiprotozoal
(Medications)

Answer 11

*Metronidazole
*Quinacrine
*Chloroquine
*Artimisinin (treats multi-drug resistant strains of falciparum malaria)