(PRELIM) CP LAB L3

C

What is the historical term for protozoans, meaning "first animals"?

a) Metazoa

b) Sarcodina

c) Protozoa

d) Archezoa

C

Which structure is a dense, dark-staining body of condensed DNA found inside the nucleus?

a) Peripheral chromatin

b) Cytostome

c) Karyosome

d) Cytopyge

B

What is the "mouth-like" opening through which some protozoa ingest food?

a) Cytopyge

b) Cytostome

c) Pseudopod

d) Vacuole

A

What is the temporary pore used by protozoa to excrete waste?

a) Cytopyge

b) Karyosome

c) Cytostome

d) Chromatoid bar

A

Which subphylum do amoebas belong to?

a) Sarcodina

b) Ciliophora

c) Mastigophora

d) Apicomplexa

D

What locomotory organelle is characteristic of the subphylum Mastigophora?

a) Cilia

b) Pseudopods

c) Gliding

d) Flagella

D

Which phylum includes organisms that move using tiny, hair-like structures?

a) Sarcomastigophora

b) Apicomplexa

c) Sarcodina

d) Ciliophora

C

Organisms in the phylum Apicomplexa are also commonly known as:

a) Flagellates

b) Ciliates

c) Sporozoans

d) Amoebas

B

What is the primary method of asexual reproduction in protozoans?

a) Budding

b) Binary fission

c) Schizogony

d) Conjugation

C

Which term describes the fine or coarse granules lining the inner nuclear membrane?

a) Karyosome

b) Endoplasm

c) Peripheral chromatin

d) Ectoplasm

B

Which morphologic form is the active, feeding, and motile stage of a protozoan?

a) Cyst

b) Trophozoite

c) Sporozoite

d) Bradyzoite

C

Which form is the dormant, resistant stage responsible for transmission?

a) Trophozoite

b) Gametocyte

c) Cyst

d) Merozoite

C

Class Lobosea consists of which group of organisms?

a) Flagellates

b) Ciliates

c) Amoebas

d) Hemoflagellates

B

Which phylum contains the species Balantidium coli?

a) Apicomplexa

b) Ciliophora

c) Sarcomastigophora

d) Mastigophora

A

Trypanosoma and Leishmania belong to which category?

a) Hemoflagellates

b) Ciliates

c) Sporozoans

d) Intestinal amoebas

C

What is the infective stage of Entamoeba histolytica?

a) Trophozoite

b) Immature cyst

c) Mature cyst

d) Flagellated form

B

Which stage of E. histolytica is responsible for tissue invasion and symptoms?

a) Cyst

b) Trophozoite

c) Metacyst

d) Pre-cyst

C

What is the diagnostic clue for E. histolytica trophozoites that confirms pathogenicity?

a) Ingested bacteria

b) Ingested yeast

c) Ingested red blood cells (RBCs)

d) Large glycogen vacuole

C

How many nuclei are present in a mature E. histolytica cyst?

a) One

b) Two

c) Four

d) Eight

B

What is the shape of the chromatoid bars in E. histolytica cysts?

a) Splinter-like with pointed ends

b) Cigar-shaped with rounded ends

c) Triangular

d) Star-shaped

D

The movement of E. histolytica trophozoites is described as:

a) Sluggish and non-directional

b) Gliding only

c) Random and spinning

d) Progressive and directional

D

What type of pseudopod is formed by E. histolytica?

a) Blunt and multiple

b) Thread-like

c) Spine-like

d) Finger-like and single

B

Which condition involves blood and mucus in the stool due to E. histolytica?

a) Giardiasis

b) Amebic dysentery

c) Primary amebic meningoencephalitis

d) Granulomatous encephalitis

B

Where does excystation of E. histolytica occur?

a) Stomach

b) Small intestine (ileocecal area)

c) Large intestine

d) Liver

A

Where does encystation of E. histolytica occur?

a) Large intestine

b) Small intestine

c) Bloodstream

d) Lungs

C

Which site is the most common for extraintestinal amebiasis?

a) Brain

b) Lungs

c) Liver

d) Spleen

B

The karyosome of E. histolytica is typically:

a) Large and eccentric

b) Small and central

c) Blot-like

d) Absent

C

How is amebiasis primarily transmitted?

a) Mosquito bite

b) Skin penetration

c) Fecal-oral route

d) Sexual contact only

B

Which laboratory preparation is used to demonstrate the motility of trophozoites?

a) Iodine wet mount

b) Saline wet preparation

c) Permanent trichrome stain

d) Acid-fast stain

C

What are chromatoid bars made of?

a) DNA

b) Glycogen

c) Condensed RNA material

d) Lipids

B

In E. histolytica, the peripheral chromatin is: a) Coarse and uneven b) Fine and evenly distributed

c) Blotchy

d) Non-existent

A

A "ground glass" appearance is used to describe the cytoplasm of which form?

a) E. histolytica trophozoite

b) E. coli cyst

c) I. butschlii cyst

d) Acanthamoeba trophozoite

D

What is the average size range of E. histolytica trophozoites?

a) 5–10 µm

b) 60–80 µm

c) 30–50 µm

d) 12–25 µm

B

Which stain is used to visualize internal nuclear structures and cytoplasmic details for confirmation?

a) Saline

b) Iodine or Permanent Stains (e.g., Trichrome)

c) Gram stain

d) India ink

D

Which nonpathogenic amoeba is morphologically identical to E. histolytica but lacks ingested RBCs?

a) E. coli

b) I. butschlii

c) E. nana

d) E. dispar

D

What is the mature number of nuclei in an Entamoeba coli cyst?

a) 1

b) 2

c) 4

d) 8

B

The chromatoid bodies of Entamoeba coli are described as:

a) Rounded and cigar-shaped

b) Splinter-like or needle-shaped

c) Ovoid

d) Rectangular

C

The karyosome of Entamoeba coli is:

a) Small and central

b) Large and central

c) Small and eccentric (off-center)

d) Blot-like

B

Which nonpathogenic amoeba is known as the "small race" of E. histolytica?

a) E. moshkovskii

b) E. hartmanni

c) E. polecki

d) E. nana

B

What is the maximum size of E. hartmanni trophozoites?

a) 5 µm

b) 15 µm

c) 25 µm

d) 40 µm

D

Entamoeba polecki is primarily a parasite of which animals?

a) Dogs and cats

b) Birds

c) Cows and sheep

d) Pigs and monkeys

D

What is a unique feature of the Entamoeba polecki cyst?

a) It has 8 nuclei

b) it is always triangular

c) It has no cell wall

d) It has only 1 nucleus (uninucleated)

C

Which amoeba has a large, blot-like karyosome and no peripheral chromatin?

a) E. histolytica

b) E. coli

c) Endolimax nana

d) Iodamoeba butschlii

C

What is the most common number of nuclei in a mature Endolimax nana cyst?

a) 1

b) 2

c) 4

d) 8

B

The cyst of Iodamoeba butschlii is easily identified by its:

a) 4 nuclei

b) Large iodine-staining glycogen vacuole

c) Splintered chromatoid bars

d) Cilia

A

Which amoeba is found in the oral cavity and has no cyst stage?

a) E. gingivalis

b) E. histolytica

c) E. hartmanni

d) E. coli

A

Entamoeba gingivalis is known to ingest which of the following?

a) White blood cells (leukocytes)

b) Red blood cells

c) Muscle fibers

d) Nerve cells

C

How is Entamoeba gingivalis transmitted?

a) Contaminated water

b) Mosquitoes

c) Mouth-to-mouth (kissing) or shared utensils

d) Undercooked pork

B

Which amoeba was first detected in sewage and is osmotolerant?

a) E. dispar

b) E. moshkovskii

c) E. polecki

d) E. hartmanni

B

The movement of Entamoeba coli is typically:

a) Progressive and rapid

b) Sluggish and multi-directional

c) Gliding

d) Rotational

A

Nonpathogenic intestinal amoebae indicate what regarding the host's environment?

a) Fecal contamination

b) Viral infection

c) High protein diet

d) Genetic immunity

A

Which nonpathogenic amoeba has blunt pseudopods and a sluggish, nonprogressive motility?

a) Endolimax nana

b) E. histolytica

c) Naegleria fowleri

d) E. gingivalis

A

What is the typical size of an Endolimax nana cyst?

a) 4–12 µm

b) 20–30 µm

c) 50–60 µm

d) 5–12 µm (trophozoite size)

C

The peripheral chromatin in Entamoeba coli is:

a) Fine and even

b) Absent

c) Coarse and uneven

d) Central

B

What disease is caused by Naegleria fowleri?

a) Granulomatous Amebic Encephalitis (GAE)

b) Primary Amebic Meningoencephalitis (PAM)

c) Amebic Liver Abscess

d) Keratitis

B

Which morphologic form of Naegleria fowleri is the tissue-invading diagnostic stage?

a) Cyst

b) Ameboid trophozoite

c) Flagellated form

d) Sporozoite

D

How does Naegleria fowleri enter the human body?

a) Ingestion of cysts

b) Through the urogenital tract

c) Through a mosquito bite

d) Through the nasal passage via contaminated water

D

Which form of Naegleria fowleri is NOT found in human tissue?

a) Ameboid trophozoite

b) Nucleus

c) Flagellated form (rarely)

d) Cyst

A

What is the typical habitat for Naegleria fowleri?

a) Warm freshwater (lakes, rivers)

b) Seawater

c) Dry soil

d) Salt mines

B

Which sign indicates meningeal irritation in N. fowleri infection?

a) Romberg's sign

b) Kernig’s sign

c) Babinski sign

d) Murphy’s sign

B

What is the primary drug used to treat Naegleria fowleri?

a) Metronidazole

b) Amphotericin B

c) Albendazole

d) Chloroquine

C

Which Acanthamoeba condition is common among contact lens users?

a) PAM

b) GAE

c) Acanthamoeba keratitis

d) Intestinal amebiasis

C

Unlike Naegleria, Acanthamoeba does NOT have which form?

a) Trophozoite

b) Cyst

c) Flagellated form

d) Nucleus

A

What are the spine-like projections on the Acanthamoeba trophozoite called?

a) Acanthopodia

b) Cilia

c) Flagella

d) Axostyles

C

Which form(s) of Acanthamoeba can be found in human tissue?

a) Trophozoite only

b) Cyst only

c) Both trophozoites and cysts

d) Flagellates

B

GAE stands for:

a) General Amebic Enteritis

b) Granulomatous Amebic Encephalitis

c) Gastric Amebic Erosion

d) Glandular Amebic Edema

C

What specimen is used to diagnose Naegleria fowleri?

a) Stool

b) Urine

c) Cerebrospinal fluid (CSF)

d) Blood

B

Which free-living amoeba can enter the host through broken skin or eyes?

a) Entamoeba coli

b) Acanthamoeba species

c) Endolimax nana

d) Giardia lamblia

B

What is the prognosis for PAM?

a) Excellent with treatment

b) Very poor; survival is rare

c) Chronic but non-fatal

d) Self-limiting

B

The conversion from a cyst to a trophozoite is called:

a) Encystation

b) Excystation

c) Sporogony

d) Schizogony

A

The conversion from a trophozoite to a cyst is called:

a) Encystation

b) Excystation

c) Binary fission

d) Syngamy

B

In the life cycle of intestinal amebae, which form is usually passed in formed stools?

a) Trophozoite

b) Cyst

c) Flagellate

d) Gamete

C

In the life cycle of intestinal amebae, which form is usually passed in liquid or diarrheic stools?

a) Cyst

b) Oocyst

c) Trophozoite

d) Egg

C

What is the "Diagnostic Stage" for E. histolytica?

a) Mature cyst only

b) Trophozoite only

c) Cysts and trophozoites passed in feces

d) Flagellated form

B

Asexual reproduction of Naegleria trophozoites where the nuclear membrane remains intact is called:

a) Mitosis

b) Promitosis

c) Meiosis

d) Budding

B

Which form of Naegleria develops under changes in ionic concentration?

a) Cyst

b) Flagellated form

c) Ameboid trophozoite

d) Trophozoite nucleus

D

What process involves trophozoites multiplying by splitting into two?

a) Encystation

b) Fertilization

c) Excystation

d) Binary fission

D

Acanthamoeba can disseminate to the Central Nervous System (CNS) via the:

a) Olfactory nerve

b) Lymphatic system

c) Digestive tract

d) Bloodstream

B

Which stage of Acanthamoeba is resistant to disinfectants and drying?

a) Trophozoite

b) Cyst

c) Flagellate

d) Larva

A

What type of drug is used to clear cysts from the gut in asymptomatic carriers?

a) Luminal agents

b) Tissue agents

c) Antifungals

d) Antibiotics only

A

Which drug is commonly used for extraintestinal amebiasis?

a) Metronidazole / Tinidazole

b) Penicillin

c) Amphotericin B

d) Iodoquinol

A

A key prevention for Acanthamoeba keratitis is to avoid using:

a) Homemade, non-sterile saline for contact lenses

b) Tap water for drinking

c) Public swimming pools

d) Shared towels

B

What is a general measure to protect food from amebic contamination?

a) Cooling food to 0°C

b) Protecting food from flies and cockroaches

c) Using more salt

d) Eating only meat

B

What is recommended for preventing infection in contaminated water sources?

a) Adding more salt

b) Posting off-limits signs

c) Heating the whole lake

d) Using colored dyes

A

To prevent amebiasis, what is the best practice regarding water and food?

a) Clean water and clean food

b) Eating raw vegetables

c) Drinking lake water

d) Shared drinking cups

A

Which drug has been recently updated as commonly included in successful Naegleria treatment?

a) Miltefosine

b) Rifampin

c) Miconazole

d) Penicillin

A

What is the focus of treatment if an infection spreads outside the intestine?

a) Strong tissue-acting drugs

b) Luminal agents

c) Topical creams

d) No treatment needed

D

For intestinal symptoms of amebiasis, the treatment focus is:

a) The brain

b) Eye drops

c) Skin lesions

d) The gut infection

B

Good personal hygiene and ________ are essential for preventing protozoan infections.

a) High-impact exercise

b) Sanitation

c) Daily vitamins

d) Sleep

B

What is the typical size range for Entamoeba histolytica cysts?

a) 2–5 µm

b) 8–22 µm

c) 30–40 µm

d) 50–100 µm

A

Which amoeba has a small, central karyosome and fine, even peripheral chromatin?

a) E. histolytica

b) E. coli

c) E. nana

d) I. butschlii

A

Which amoeba is non-motile in its cyst stage and has a thick protective wall?

a) All cyst-forming amoebas

b) E. histolytica

c) Only Naegleria

d) Only E. coli

B

The cytoplasm of Entamoeba coli is:

a) Finely granular

b) Coarsely granular

c) Clear

d) Striated

C

Iodamoeba butschlii trophozoites have a karyosome that is:

a) Small and central

b) Blot-like

c) Large, central or eccentric with achromatic granules

d) Absent

C

Which amoeba's cyst is spherical, ovoid, or ellipsoid and typically has 4 nuclei?

a) E. coli

b) I. butschlii

c) Endolimax nana

d) E. polecki

B

Which organism moves using pseudopods and is an example of the Sarcodina?

a) Giardia

b) Amoeba

c) Balantidium

d) Plasmodium

A

A dense body of chromatin inside the nucleus is the:

a) Karyosome

b) Cytostome

c) Pellicle

d) Flagellum

C

Which phylum lacks definite locomotory organelles in adult stages?

a) Ciliophora

b) Sarcomastigophora

c) Apicomplexa

d) Sarcodina

B

What is the common name for Naegleria fowleri?

a) Heart-eating amoeba

b) Brain-eating amoeba

c) Liver-eating amoeba

d) Skin-eating amoeba