CHAPTER 3: AMOEBAS

Question 1

First identified the taxonomy of Amoeba coli (E. histolytica) in St. Peterburg, Russia

Answer 1

Fedor Losch (1875)

Question 2

Description of 3 species as being human parasites.

Answer 2

Clifford Dobel (1919)

Question 3

Description of 3 species of amoebas

Answer 3

E. histolytica - 4 nuclei
E. coli - 8 nuclei
E. gingivalis - in oral cavity

Question 4

Identified E. hartmanni, morphologically similarly in size w. other amoebas

Answer 4

von Prowazek (1912)

Question 5

identified E. dispar, no ability ti cause disease in human and animals

Answer 5

Emile Brumpt (1925)

Question 6

ameba isolates from:

a. asymptomatic
b. amebic dysentery

Answer 6

Sargeaunt and Williams

Question 7

ASYMPTOMATIC

Answer 7

Nonpathogenic zymodemes

Question 8

AMEBIC DYSENTRY

Answer 8

Pathogenic zymodemes

Question 9

General Characteristics of Protozoans

Answer 9

• animal-like protozoans
• unicellular
• multiply by BINARY FISSION
• no cell wall (PERIPLAST)
• 1 nucleus
• vacuolated
• facultative or obligate

Question 10

Organs for Locomotion

Answer 10

• flagella
• pseudopods
• cilia
• apical complex not used for locomotion

Question 11

Organism that contains APICAL COMPLEX

Answer 11

Plasmodium spp.

Question 12

2 similar Entamoeba species that can only be distinguished by Polymerase Chain Reaction (PCR)

Answer 12

• histolytica and dispar

Question 13

Life Cycle of an Amoeba

Answer 13

• Trophozoites
• Pre-cyst
• Cyst
• Metacyst

Question 14

2 regions of cytoplasm

Answer 14

• Endoplasm

- Ectoplasm

Question 15

single mass of aggregate of granules, maybe near the center of the cell or at times surrounded by chromatin particles that appear to be arranged on a chromatic network or chromatin granules lining the nuclear membrane

Answer 15

Nucleus/ Karyosome

Question 16

maintain normal osmotic pressure by collecting excess water within their cytoplasm and expelling it outside

Answer 16

Contractile Vacuole

Question 17

connects the nucleoplasm to the endoplasm

Answer 17

Nuclear membrane

Question 18

envelops endoplasm; discharges metabolism

Answer 18

Ectoplasm

Question 19

locomotion of amoeba; “false feet”

Answer 19

Pseudopods

Question 20

locomotion of flagellates; hair-like projections of the cytoplasm arising in the kinetoplast functions as locomotion of organelles

Answer 20

Flagella

Question 21

locomotion of ciliates; arise from basal granules within the ectoplasm and distributed over the surface of the body

Answer 21

Cilia

Question 22

responsible for food waste and excretion discharge

Answer 22

Cytopyge

Question 23

present in ciliates

Answer 23

Cell anus

Question 24

collects fluid wastes that are ejected from the cell

Answer 24

excretory vacuole

Question 25

in trophozoite stage it functions as the control portion of the intake and output of food secretions, excretions and maintains normal concentration of the plama substance by being PERMEABLE to some substance and IMPERMEABLE to others

Answer 25

Plasma membrane

Question 26

The process of asexual multiplication where the nucleus of the parent cell divides mitotically resulting to two identical daughters

Answer 26

Binary Fission

Question 27

from trophozoites to cyst

Answer 27

Encystation

Question 28

from cyst to trophozoite

Answer 28

Excsytation

Question 29

Factors responsible of encystation

Answer 29

- deficiency or overabundance of food supply - excess catabolic products - marked change in pH - dessication of the medium - depletion or excess supply of oxygen - overpopulation

Question 30

factors of excystation

Answer 30

- osmotic changes in the medium - enzymatic action of the enclosed organism on the inner surface of the cyst wall - change of favorable pH, food supply, oxygen and enzymatic action to host tissue

Question 31

Trophozoite Stage

Answer 31

- motile - feed and multiplies - presence of pseudopods - vegetative state - found in diarrheic stool - cannot mature once excreted - never found in iodine stain

Question 32

Cyst Stage

Answer 32

- nonmotile - non-feeding - infective stage - found in formed stool - transmitted through contaminated water and food - better observe in permanent stains

Question 33

Largest Entamoeba species

Answer 33

E. coli

Question 34

Smallest species

Answer 34

Endolimax nana

Question 35

8 nuclei

Answer 35

E. coli

Question 36

4 nuclei

Answer 36

E. histolytica

Question 37

1 nucleus

Answer 37

Iodamoeba butschlii

Question 38

Largest endosome

Answer 38

Endolimax nana

Question 39

Largest iodine staining vacuole

Answer 39

Iodamoeba butschlii

Question 40

Peripheral Chromatin

Answer 40

Blastocystis hominis

Question 41

Central karyosome

Answer 41

E. histolytica

Question 42

Eccentric karyosome

Answer 42

E. coli

Question 43

Specimen consideration for soft, liquid, loose stool

Answer 43

TROPHOZOITES

Question 44

Specimen consideration for formed or semi-formed

Answer 44

CYST

Question 45

To observer motility use

Answer 45

NSS solution

Question 46

To observe structure

Answer 46

Iodine soln

Question 47

To confirm species

Answer 47

Permanent stains: - iron hematoxylin (red) - trichrome (blue)

Question 48

All amoeba have cystic stage except

Answer 48

E. gingivalis

Question 49

All amoeba inhabit the colon/ intestine except

Answer 49

E. gingivalis

Question 50

All amoeba are commensal except

Answer 50

E. histolytica

Question 51

Subphylum of Amoebas

Answer 51

Sarcodina

Question 52

Class

Answer 52

Lobosea

Question 53

Intestinal Parasites

Answer 53

- E. histolytica - E. dispar - E. hartmanii - E. moshkovskii - E. coli - Iodamoeba butschlii - E. polecki - E. chattoni - Endolimax nana

Question 54

Sister species of Entamoebas

Answer 54

dispar and histolytica

Question 55

Small race

Answer 55

E. hartmanii

Question 56

Initially described in sewage in Russia, common anaerobic sediments worldwide. Also, it causes human infection "E. histolytica-like ameba". Lives at temp. rnage of 20C to 28C but thrives in the test tube at 37C

Answer 56

E. moshkovskii

Question 57

Extraintestinal Parasites

Answer 57

- E. gingivalis - Acanthamoeba - Naegleria fowleri