Micro Exam 4 Protozoa

What is part of Phylum Sarcomastigophora

Zooflagellates

What types of reproduction do Protozoans experience?

Asexual: binary fission

Sexual: Conjugation, which is the exchange of gametic nuclei between paired protozoa of opposite mating types.

What are the locomotory organelles?

Cilia

Flagella

Pseudopodia all of which are cytoplasmic extensions

Can protozoa be nonmotile?

Yes, they can be nonmotile

What is Encystment

The formation of a cyst as a way to survive harsh environments (desiccation and high UV light levels). Low metabolic activity.

Functions:

• Protection from changes in environment

• nuclear reorganization and cell division site

• transfer from one host to another

Excystation

the vegetative (active) from of the cyst leaves (triggered by return to favorable enviornment)

What is a trophozoite, and under what conditions is it released in parasitic protozoa?

A trophozoite is the vegetive (active) form of a protozoan parasite. It is released from the cyst during excystation, which is typically triggered when the parasite enters a new host and encounters favorable internal conditions

Types of vacuoles in protozoa

Contractile vacuoles: osmoregulatory, expel water

Phagocytic vacuoles: site of food digestion

Secretory vacuoles: contain enzymes for specific function (excytation)

What is the importance of protozoa?

Important link in food chains and food webs.

• Food webs: complex interlocking series of food chains (make up large part of plankton in aquatic habitiats)

• Food chains: series of organisms, each feeding on the preceding one

Where are terrestrial protozoa found?

decaying organic matter and soil

Where are protozoa primarily found?

Moist habitats (most are free-living in aquatic enviornments)

Can protozoa be parasitic?

Yes, to plants and animals.

Protozoa characteristics?

Unicellular, usually motile and lack cell wall

Chemoorganoheterotrophs (like humans)

Never mutlicellular!!

What’s special about protozoa’s gelatinous cytoplasm

provides them rigidity

What does the macronucleus of protozoa do?

Trophic activities and regenerative processes.

What’s special about Hydrogenosomes

They are membrane-delimited organelles that are found in some anaerobic protozoa and have a unique electron transfer system (uses protons as terminal electron acceptors)

What are the two types of nutrition in protozoa

1. Holozoic nutrition (cell eating): nutrients acquired by phagocytosis

2. Saprozoic nutrition (cell drinking): nutrients acquired by pinocytosis, diffusion, or carrier-mediate transport

What is a cytostome?

a “cell mouth” used by some ciliates for phagocytosis

What is a kinetoplast?

region containing mitochondrial DNA

What does Giardia lambllia cause?

Giardiasis: gastrointestinal disorder

What is Trichomoniasis (caused by Trichomonas vaginalis)?

sexually transmitted disease

What are Trypanosomes?

They are hemoflagellates (one flagella) and are important blood pathogens (African sleeping sickness)

What do Testate amoebae do?

They form a house or loose fitting shell around themselves made from inorganic material.

Where is Endamoeba blattae found?

intestines of insects

Entamoeba histolytica

parasitic amoeba of the intestines (dysentery)

What does the phylum apicomplexa lack?

it lacks locomotor organelles (except for male gametes and zygotes)

What is special about Phylum Apicomplexa?

They have fibrils, tubules, vacuoles, and other organelles at one end of the cell.

What is Conoid?

in the apical complex, spirally arranged fibers.

What is Rhoptry?

In the apical complex contains materials that are secreted and aid in penetration of host cell

Apicomplexan life cycles?

involves mammal and mosquito.

Asexual and sexual phases

Asexual: Schizogony

Oocyst: produced during sexual phase

What does casamatta consider as fungi?

Microspora

Who does microspora affect

insects

What is phylum microspora? 4 things

1. obligatory intracellular parasites

2. lack mitochondria

3. pest control

4. some could be applied to patients with AIDS

What does Nosema bombycis do?

causes pebrine disease in silkworms

What is phylum ascetospora? 3 things

1. Spore with one or more spiroplasma

2. No polar capsules

3. parasitic in all invertebrates

Who does phylum myxozoa affect?

fish

What is the food processing order of Phylum Ciliophora? 5 steps

1. enters cytostome

2. phagocytic vacuole

3. fuses with lysosome

4. digestion occurs vacuole fuses with cytoproct

5. waste is emptied outside

What does Entodinium cause in cattle?

commensals in rumens

what does Nyctotherus cause in frogs?

commensals in colon of frogs

What are the 3 important sporozoan genera and why?

1. Plasmodium: malaria

2. Cryptosporidium: cryptosporidiosis

3. toxoplasma: toxoplasmosis

Why do we boil water?

Giardia lamblia

How is phylum Sarcomastigophora organized?

organized by molecular methods like 18s rRNA