15. Protozoa

Question 1

What is a protozoa?

Answer 1

a single celled organism with nuclei

Question 2

what does Protozoa mean?

Answer 2

first animal

Question 3

what kingdom is Protozoa part of?

Answer 3

Protists

Question 4

what does the kingdom Protista include?

Answer 4

single-celled organisms, including the Dinoflagellates, and the single celled algae

Question 5

in general, do Protozoans photosynthesize?

Answer 5

no

Question 6

are Protozoans generallt motile?

Answer 6

yes

Question 7

where can protozoans live in the body?

Answer 7

in all parts of the body, including the gut, mouth, skin, blood, live, spleen, genital tract, lungs brain and heart

Question 8

what are the different groups of Protozoa, of which parasitize humans?

Answer 8

Amoeba

Flagellates

Ciliates

Sporozoa

Question 9

what Protozoan group is Entamoeba in?

Answer 9

Amoeba

Question 10

what Protozoan group are Giardia, Trichonomas, Trypanosoma and Leishmania in?

Answer 10

Flagellates

Question 11

do protozoa have rigid cell walls?

Answer 11

no

Question 12

how do protozoa digest their food?

Answer 12

in vacuoles

Question 13

how do protozoa gain entry to a host?

Answer 13

orally or through the bite of a blood-sucking vector

Question 14

T/F

•

From the point of view of functional and physiological

complexity, a protozoan is more like an animal than like

a single cell.

Answer 14

True

Question 15

define niche selection

Answer 15

selected to live in a specific essential niche

defined by anatomical, physiological and biochemical

features of the site

Question 16

what is pathogenesis related to?

Answer 16

the niche, the metabolic requirements of the parasite and the population density

Question 17

what are some ways that protozoa will feed/ingest nutrients?

Answer 17

active transport, phagocytosis, or pinocytosis

Question 18

where does digestion take place in protozoa?

Answer 18

in a vacuole through lysosomal enzymes

Question 19

how is waste excreted in protozoa?

Answer 19

by diffusion or exocytosis

Question 20

what protozoan group is Balantidium coli in?

Answer 20

ciliates

Question 21

how do amoebas move?

Answer 21

pseudopodia

Question 22

how do flagellates and ciliates move?

Answer 22

cilia and flagella

Question 23

how are cilia and flagella microtubules arranged?

Answer 23

9+2

Question 24

how do protozoa reproduce asexually?

Answer 24

binary fission

multiple fission

budding

i.e. variations of mitotic division

Question 25

how do protozoa reproduce sexually?

Answer 25

gamete fusion conjugation

Question 26

what is schozogony?

Answer 26

multiple fission

Question 27

describe binary fission

Answer 27

mitosis leads to the cell splitting yielding two daughter cells

Question 28

describe multiple fission

Answer 28

nucleus undergoes multiple divisions before the cell divides - gives rise to multiple daughter cells

Question 29

which protozoa are more likely to reproduce sexually, through gamete fusion?

Answer 29

the ones with an insect vector phase

Question 30

define trophozoite

Answer 30

any stage in a protozoan’s life cycle which can ingest nutrients. In practice it refers to the motile form (pseudopods, cilia, flagella)

Question 31

define cyst

Answer 31

Non‐motile form, protected by a membrane. Often the \*infective stage\*

Question 32

define excystation

Answer 32

process of emergence of the trophozoite from the cyst

Question 33

what disease does *Giardia intestinalis* cause?

Answer 33

giardiasis

Question 34

where is giardiasis acquired?

Answer 34

contaminated water

Question 35

what disease does *Trichonomas vaginalis* cause?

Answer 35

vaginosis

Question 36

what disease does *Trypanosoma brucei gambiense* cause?

Answer 36

african sleeping sickness

Question 37

what disease does *Entamoeba histolytica* cause?

Answer 37

Amoebic dyentery

Question 38

how is african sleeping sickness transmitted?

Answer 38

the tsetse fly

Question 39

what disease does *Tripanosoma cruzi* cause?

Answer 39

chagas disease

Question 40

how is *T. cruzi* transmitted?

Answer 40

the kissing bug

Question 41

what disease does *Leishmania* spp. cause?

Answer 41

leishmaniasis

Question 42

how is leishmaniasis transmitted?

Answer 42

sand flies

Question 43

what is the phylum of *Entamoeba histolytica*?

Answer 43

Sarcodina

Question 44

who is in the phylum Mastigophora?

Answer 44

*Giardia intestinalis, Trichomonas vaginalis, , Trypanosoma brucei gambiense, Trypanosoma cruzi, and Leishmania?*

Question 45

what disease does *Balantidium coli* cause?

Answer 45

Balantidial dyentery

Question 46

how is *B. coli* contracted?

Answer 46

contaminated water

Question 47

what phylum is *B. coli* in?

Answer 47

Ciliata

Question 48

what disease does *Plasmodium* spp. cause?

Answer 48

malaria

Question 49

how is *Plasmodium* spp. transmitted?

Answer 49

Anopheles mosquito

Question 50

what phylum is *Plasmodium* spp. in?

Answer 50

Sporozoa (apicomplexans)

Question 51

what disease does *Toxoplasma gondii* cause?

Answer 51

toxoplasmosis

Question 52

what phylum is *Toxo* in?

Answer 52

Sporozoa (apicomplexans)

Question 53

how can *Toxo* be contracted?

Answer 53

raw meat, cat feces

Question 54

what disease does *Cryptosporidium* cause?

Answer 54

Diarrhea

Question 55

what phylum is *Cryptosporidium* in?

Answer 55

Sporozoa (apicomplexams)

Question 56

how is *Cryptosporodium* spread?

Answer 56

humans, animals

Question 57

What is this?

Answer 57

Malaria - *Plasmodium* spp.

Question 58

What is this?

Answer 58

Toxoplasmosis *(Toxoplasma gondii)*

Question 59

What is this?

Answer 59

Criptosporidiosis - *Cryptosporidium parum*

Question 60

What are the symptoms of *Toxo?*

Answer 60

Does not cause symptoms in most people. Can cause fatalities in unborn children and in AIDS patients.

Question 61

how can *Toxo* be prevented?

Answer 61

Thoroughly cook all meats, be careful handling cat litter, feed cats commercial cat food, cover sand boxes when not in use and wash all fruits and vegetables before eating.

Question 62

what are the symptoms of *Plasmodium* spp.?

Answer 62

fever, headache and vomiting, can be fatal

Question 63

how can *Plasmodium* spp. be prevented?

Answer 63

Spread by mosquito bites. The use of DDT in the U.S. and many other countries brought malaria under control. It is still a problem in many developing countries.

Question 64

what are the symptoms of *C. parvum?*

Answer 64

Diarrhea. May also cause vomiting, headache, fever and stomach cramps. Can be fatal to those in poor health.

Question 65

how can *C. parvum* be prevented?

Answer 65

Use an approved water filter, an approved brand of bottled water or boil water for 1 minute. Avoid drinking water from lakes and rivers.

Question 66

T/F • Apicomplexa consists of all parasitic species

Answer 66

True

Question 67

do apicomplexa have cilia or flagella?

Answer 67

not usually

Question 68

what is the hallmark of Apicomplexa

Answer 68

apical complex structure

Question 69

what do most Apicomplexa possess

Answer 69

the apicoplast organelle

Question 70

what is the appearance of the apical complex?

Answer 70

An organ complex of the Apicomplexa that appears as a conical structures on the tapered end (or the apical end) of the cell, and contains rhoptries, micronemes, dense granules, polar rings, and a conoid.

Question 71

what is the mechanism of the apical complex?

Answer 71

• Rhoptries, micronemes and dense granules discharge substances into the host cell during the invasion process through a system of ducts which open up at the apical end. • The substances released play a crucial role in destabilizing the host cell membrane and in formation of an invasion pit.

Question 72

name the structures

Answer 72

Question 73

what is the use of the apical complex?

Answer 73

it is involed in penetrating the host

Question 74

how many membranes does the apical complex have?

Answer 74

4

Question 75

why is the apicomplast also known as the plastid?

Answer 75

drugs against chloroplasts and prokaryotes also kill apicomplexan parasites

Question 76

how did the apicomplast likely become encased in four membranes?

Answer 76

via a secondary endosymbiotic event - the promary endosymbiosis gives rise to 2 membranes, and then if that is endocytosed again you will have 4 membranes

Question 77

what is primary endosymbiosis?

Answer 77

the capture of a cyanobacterium by a eukaryotic heterotroph - the cyanobacterium would have modified during evolution to give rise to a plastid with two surrounding membranes

Question 78

what is secondary endosymbiosis?

Answer 78

proposed to be the engulfment of a red algae containing a chloroplast by a eukaryotic heterotroph - the red algae would have become the plastic with four ssurrounding membranes

Question 79

is the apicomplast a chloroplast?

Answer 79

NO

Question 80

do apicomplasts have chloroplasts?

Answer 80

NO they are absent

Question 81

is the apicomplast vital for the pasite's survival?

Answer 81

yes

Question 82

what is the apicomplast possibly involved in?

Answer 82

lipid metabolism

Question 83

if we remove the apicomplast, what is the effect on the parasite?

Answer 83

they will survive but they will not be able to invade new hosts