Amoebas

Question 1

Protozoa

Answer 1

Organisms in a number of phyla
Highly diverse group
unicellular, eukaryotic

Question 2

Trophozoite

Answer 2

Active feeding stage of a protozoan (vegetative stage)

Question 3

Cyst

Answer 3

Environmentally resistant dormant stage of protozoan

-spherical, with a thick cyst wall

Question 4

Pellicle

Answer 4

Entire outer envelope covering protozoa

Question 5

Glycocalyx

Answer 5

Carbohydrate above plasma membrane

Question 6

Endosome (karyosome)

Answer 6

Like a nucleolus (but does not dissapear during mitosis)

Question 7

Chromatoidal bars

Answer 7

Chromatoid bars or bodies are masses containing RNA found in young entamoeba cysts

Question 8

Entamoeba Histolytica: Cysts

Answer 8

Asymptomatic infection trophozites encyst as feces forms

spherical to oval in shape

Question 9

Organism is associated with flask-shaped lesions in intestines

a. entameba histolytica
b. entameba coli
c. naegleria fowleri
d. acanthameba spp.

Answer 9

Entameba Histolytica

Question 10

Organism is not a parasite, but a commensal

a. entameba histolytica
b. entameba coli
c. naegleria fowleri
d. acanthameba spp.

Answer 10

Entameba Coli

Question 11

Outbreaks in immunocompetent people are often associated with contaminated contact lens solutions

a. entameba histolytica
b. entameba coli
c. naegleria fowleri
d. acanthameba spp.

Answer 11

Acanthameba spp.

Question 12

Infection is associated with warm water lakes and streams, especially when water is forced up the nose.

a. entameba histolytica
b. entameba coli
c. naegleria fowleri
d. acanthameba spp.

Answer 12

Naegleria Fowleri

Question 13

Centrally located endosome in nucleus, early cysts with blunt chromatoid bars, and mature cysts with 4 nuclei

a. entameba histolytica
b. entameba coli
c. naegleria fowleri
d. acanthameba spp.

Answer 13

Entameba Histolytica

Question 14

Entamoeba Coli

Answer 14

Lives on intestinal bacteria, other protozoa, yeast, maybe an occasional host cell

Question 15

Entamoeba Coli: Trophozoites

Answer 15

eccentrally located endosome
thicker, darker staning chromatin granules
food vacuoles often contain bacteria

Question 16

Entamoeba Histolytica: Trophozoites

Answer 16

centrally located endosome
thin fibrils entending to nuclear membrane
food vacuoles common, some may contain host red blood cells

Question 17

Infection: EH

Answer 17

cyst pass in feces, must be ingested (mouth-butt route)
contaminated water supplies, filth flies, cockroaches
sexual practices
use of human feces (night soil) as fertilizer

Question 18

Symptoms: EH

Answer 18

Diarrhea, abdominal pain, cramps , vomiting , bloody diarrhea
not typically a disease of children
more common in tropics

Question 19

Treatment: EH

Answer 19

Metranidazole, several other drugs

Antibiotics may be used to treat accompanying secondary bacterial infections

Question 20

Entamoeba Coli: Cysts

Answer 20

ecentrally located endosome; thicker dark staining chromatin granules
more than 4 nuclei (8 in mature cyst)
chromatodial bars with jagged, splintered ends in young cysts

Question 21

Naegleria fowleri

Answer 21

ameba trael via olfactory nerves, through cribriform plate to brain
common aquatic ameba but infection is rare
naegleria is sensitive to amphotericin b

Question 22

Acanthameba Spp

Answer 22

attacks the cornea of the eye

immunocompromised patients may cause skin, lung, CNS infections