Eukaryotic Diversity Flashcards
What are the major characteristics of protozoans?
- unicellular, nonphotosynthetic, motile microorganisms that live in a variety of habitats.
- free-living or parasitic and can cause illness
- asexual or sexual reproduction or both
- all have a plasma membrane
- some lack some organelles or they can have unique organelles
- some have pellicles, they can have an ectoplasm and an endoplasm
- have different structures they use for feeding: cytostome and a cytoproct
- heterotrophic
- have either flagella, cilia, or pseudopodia that help them move.
- some have contractile vacuoles and some could alter or lack mitochondria.
What are pellicles?
a membrane that contains protein bands that for protection
What are the layers under the cytoplasm that are found in some protozoans?
1) ectoplasm (outer gel layer)
2) endoplasm (fluid region of cytoplasm).
What is a cytosome?
takes in food through the process of phagocytosis
What is a cytoproct?
functions in the exocytosis of wastes in the protozoa
What are contractile vacuoles?
get rid of excess water in the membrane
What is a trophozoite?
active, feeding, and growing form of a protozoan
What is a cyst?
inactive form of a protozoan that contains a protective wall
- when the environmental conditions become harsh for trophozoite it becomes a cyst
What are fornicata?
contain four free flagella, no mitochondria, and a pair of equal nuclei
- often parasitic and can form cysts
What is an example of fornicata?
Giardia lamblia: Causes diarrheal illness and is spread through water supplies that are contaminated by the cysts from feces.
What are parabasalids?
contain no mitochondria and four free flagella
- have one attached flagellum and basal bodies
- can either be parasitic or symbiotic
- DON’T form cysts
- have kinetoplastids (modified mitochondria)
- live in the guts of animals (endosymbionts)
What is an example of parabasalids?
Trichomonas vaginalis causes trichomoniasis which is a sexually transmitted disease.
What are euglenozoans?
photosynthetic or heterotrophic and contain flagella.
What are examples of euglenozoans?
1) Euglena
2) Trypanosoma (African sleeping sickness, Chagas disease)
3) Leishomania (causes Leishmaniasis)
What supergroup are fornicata, parabasalids, and euglenozoans a part of?
the supergroup excavata
What is african sleeping disease?
a disease caused by T.brucei that affects the blood and the brain
What is Chagas disease?
disease caused by T.cruzi that affects the heart tissue or digestive system tissue
What are apicomplexans?
intracellular parasites with an apical complex located at one end of the cell
- apical complex enables the parasite to enter host cells
- have complex life cycles that depend on being transmitted between various hosts
- can infect many kinds of animal cells.
What are examples of apicomplexans?
1) Plasmodium (Malaria)
2) Cryptosporidium parvum
3) Theileria (Babesia) microti
4) Toxoplasma gondii
What does plasmodium cause?
agent of malaria that is transferred via an insect vector
- malaria affects red blood cells and can lead to anemia as they lyse (MAJOR KILLER)
- the top eukaryotic pathogen.
What is Cryptosporidium parvum?
1) When cysts contaminate drinking water, this causes epidemic diarrhea
2) It causes intestinal symptoms.
What is Theileria (Babesia) microti?
1) Transmitted by a tick
2) Causes recurring fevers that could be fatal
What is Toxoplasma gondii?
1) Causes toxoplasmosis (associated with birth defects)
2) transmitted by undercooked meat, unwashed produce, cat feces