1.6 The Protists Flashcards
general characteristics of the Protists.
Eukaryotic
Organisms that are not fungi, plants, or animals
Mostly unicellular with some colonial and multicellular forms
Lack specialized tissue organization
Live in aquatic and terrestrial environments with water
May be heterotrophic or autotrophic
Classified into three informal groups: Protozoa, Algae and Water Molds
three major informal groups into which the Protists are divided.
Algae (plant-like), Protozoa (animal-like), and water-mold (fungus-like)
Types of motility of protozoa:
flagella, cilia, and pseudopodia
Stages in life cycle - trophozoite
the feeding and growth part of their life cycle,
Stages in life cycle - cyst
encapsulated cell which can survive drying and other adverse environmental conditions
a cell with a protective wall, and the process by which a trophozoite becomes a cyst is called encystment
Reproductive mechanisms
Most protists have both asexual and sexual phases Asexual reproduction Binary fission Multiple fission Budding Sexual reproduction Conjugation Fusion of gametes
Plasmalemma
protist cell membrane
Pellicle
rigid bands of proteins
ectoplasm
outer gel layer
endoplasm
inner gel layer
cytosome
mouth-like opening in cell
Amoebozoa
have pseudopodia Use pseudopodia for feeding and movement Most reproduce by asexual division Examples: Entamoeba histolytica: causes amoebic dysentery Naegleria fowleri: brain parasite Slime mold
Chromoaveolata
plastid from secondary endosymbiosis
Includes autotrophic, mixotrophic and heterotrophic protists
Includes Apicomplexans, Dinoflagellates, and Diatoms
Excavata
have cytostomes; feed by current produced by flagella
Apicomplexans
All are parasitic Nonmotile in mature form Form small, infectious spores Example: Plasmodium vivax
