BIOL 1002 : Bio Exam 2 / Chap 20-21
Document Summary
Excavates: move via flagella, have a feeding groove, heterotrophic and lack mitochondria. The two largest subgroups of the excavates are the diplomonads and the parabasalids. Diplomonads: both free living and symbiotic species, have two nuclei, multiple flagella. Giardia is a member of this group infection results from drinks untreated water causing diarrhea etc. Parabasalids: anaerobic, all known species are symbiotic and some are parasitic. Trichomanas vaginalis is a sexually transmitted member of this group males can often be asymptomatic. Euglenozoans: have distinctive mitochondria, move via flagella, mixed nutritional methods. There are two major groups, the euglenids and the kinetoplastids. Euglenids: most are freshwater, have 1-3 flagella, primarily photosynthetic but can switch to heterotrophic in the dark, many lack a rigid cell wall, have a photoreceptor called an eyespot, named after euglena (see fig. Kinetoplastids: one flagellum, both free living and symbiotic species.
