Protazoan Organisms

Question 1

Protazoan Organisms

Protozoa

Answer 1

Eukaryotic organisms

Ecologically important

Cause serious human dieases

Question 2

Protazoan Organisms

How do the protozoa that are motile get around?

Answer 2

Eukaryotic cilia or flagella

Or actin-myosin cytoskeletal mechanisms

Question 3

Protazoan Organisms

Types of host when a parasite uses multiple hosts

Answer 3

Definitive host

Intermediate host

Question 4

Protazoan Organisms

Definitive host

Answer 4

A host used by parasites that use multiple hosts

Where parasite reproduces asexually

Question 5

Protazoan Organisms

Intermediate host

Answer 5

A host used by parasites that use multiple hosts

Where sexual development occurs

Question 6

Protazoan Organisms

How many hosts do parasites use?

Answer 6

Either one or multiple depending on the parasite

Question 7

Protazoan Organisms

Excavata

Answer 7

Part of the protist supergroup

Named after “excavated” feeding grove in cell

Food particles taken into the cells by phagocytosis

Question 8

Protazoan Organisms

Another name fro the feeding grove in excavata cells?

Answer 8

Cytostome

Question 9

Protazoan Organisms

Process of phagocytosis in excavates

Answer 9

Question 10

Protazoan Organisms

Four flagellates that cause human diseases

Answer 10

• Trichomonas*
• Giardia*
• Leishmania*
• Trypanosoma*

Question 11

Protazoan Organisms

Trichomoniasis

Answer 11

Sexually transmitted infection

Caused by Trichomonas vaginalis

Produces vaginits in females

May cause urethritis in males

Question 12

Protazoan Organisms

Symptoms of trichomoniasis

Answer 12

Pain

Dysuria (painful urination)

Discharge

Question 13

Protazoan Organisms

Life cycle of Trichomonas vaginalis

Answer 13

Question 14

Protazoan Organisms

How long can Trichomonas vaginalis last outside the host for?

Answer 14

Normally 1-2 hours

Up to 24 hours in water, semen or urine

Question 15

Protazoan Organisms

Pathogenesis of Trichomoniasis

Answer 15

Infection caused by contact transmission to genital endothelial cells

These cells are destroyed and inflamation occurs

Question 16

Protazoan Organisms

Is Trichomonas invasive?

Answer 16

No

It adheres to the vaginal endothelial cells

Question 17

Protazoan Organisms

What is the treatment for trichomoniasis?

How effective is it?

Answer 17

Oral metronidazole

Cures 95% of cases

Question 18

Protazoan Organisms

Trypanosoma

Answer 18

Is motile

Has a single flagellum

Has two hosts

Question 19

Protazoan Organisms

Trypsanosoma hosts

Answer 19

Mammals

Tsetse fly

Question 20

Protazoan Organisms

What is a vector in terms of parasites?

Answer 20

An agent that carries and transmits the infectious organism

Most commonly insects

Question 21

Protazoan Organisms

What are the two forms of trypanosomiasis?

• What the cause

Answer 21

• Trypanosoma brucei*
• Causes sleeping sickness
• Trypanosoma cruzi*
• Causes chagas’ disease

Question 22

Protazoan Organisms

Which is the African form of the Trypanosoma species?

Answer 22

Trypanosoma brucei

Question 23

Protazoan Organisms

Which is the American form of Trypanosoma species?

Answer 23

Trypanosoma cruzi

Question 24

Protazoan Organisms

Basic life cycle of Trypanosoma brucei (in human host)

Answer 24

1. Tsetse fly injects metacyclic trypomastigotes into human
2. Metacyclic trypomastigotes transform into bloodstream trypomastigotes
3. Trypomastigotes mutliply by binary fission
4. Trypomastigotes taken back up by tsetse fly

Question 25

# Protazoan Organisms Basic life cycle of *Trpanosoma brucei* (in tsetse fly)

Answer 25

1. Trypomastigotes taken back up by tsetse fly 2. Bloodstream trypomastigotes transform into procyclic trypomastigotes in flys midgut 3. Procyclic trypomastigots multiply by binary fission 4. Procyclic trypomastigotes leave the midgut and transform into epimastigotes 5. Epimastigots mutliple in salvitory gland 6. They transform into metacyclic trypomastigotes 7. Metacyclic trypomastigotes injected into human when fly feeds

Question 26

# Protazoan Organisms What's different about members Excavata's mitochondria?

Answer 26

Often long tubular shape or disc-shaped

Question 27

# Protazoan Organisms Where is the mitochondrial DNA in Excavata mitochonria?

Answer 27

In a special structure called a **Kinetoplast**

Question 28

# Protazoan Organisms What is the reservoir for sleeping sickness?

Answer 28

Human and cattle

Question 29

# Protazoan Organisms Antigenic variation

Answer 29

When a pathogen can change their cell surface antigens Fools immune defences

Question 30

# Protazoan Organisms How does Trypanosoma reproduce

Answer 30

Longitudinal binary fission In mammalian hosts Extracellular

Question 31

# Protazoan Organisms Basic symptoms of Trypanosomiasis

Answer 31

Hemorrhaging Heacdache Fever Skin rash Impaired mental status

Question 32

# Protazoan Organisms What further symptoms can a sufferer of Trypasomiasis progress to?

Answer 32

Eventual diminished alertness Indistinct speech Tremors Coma Coma can lead to death

Question 33

# Protazoan Organisms Treatment used for trypanosmiasis

Answer 33

If the CNS is involved * Melarsporol If there is no CNS involvement * Pentamidine or Eflorinthine