BIOL-1116 Final

• evidence for eukaryotic development found in fossils dating as far back as 2.7 bya.
• moderate diversity of single-celled eukaryotes was present by 1.8 bya.
• early eukaryotes had a nucleus, flexible membrane, and a cytoskeleton.
• oldest known fossils that can be taxonomically classified are those of red algae, dating back to 1.2 bya.
• A blanket term used for all photosynthetic protists is: Algae.
• Large multicellular organisms first appear during the Ediacaran period, (635-541 mya).
• Mitochondria and plastids began as prokaryotic organisms.
• not all eukaryotes have plastids.
• heterotrophic eukaryotes acquired the ability to photosynthesize by engulfing cyanobacteria.
• plastid bearing cells gave rise to two major lineages, red algae and green algae.
• Multicellular colonies consisted of simple filaments, balls, or sheet cells.
• Choanoflagellates represent the closest living protist relative of animals.
• origin in multicellularity in animals required adherence and cellular communication methods.
• the four supergroups of eukaryotes are: Excavata, SAR, Archaeplastida, and Unikonta.
• Excavata organisms have a deep groove down one side of their body.
• Excavata includes parasites and predatory-photosynthetic species.
• Diplomonads and Parabasalids are a clade of excavata. they have reduced mitochondria, and lack plastids. most live in anaerobic environments.
• Euglenozoans are heterotrophs, photosynthetic autotrophs, and parasites. all members have a rod with a crystalline structure within their flagella.
• SAR supergroups contains three large clades: Stramenopila, Alveolata, and Rhizaria.
• Both Stramenopila and Alveolate are photosynthetic organisms.
• Rhizaria includes many species of amoebas.
• Diatoms are unicellular algae. cell wall composed of silicon dioxide embedded matrix. found in both salt and fresh water.
• Brown Algae are large, complex multicellular algae mainly found in marine environments. analogous features to plants.
• Alveolates are named after the enclosed sacs located under the plasma membrane.
• Dinoflagellates have a double flagella. they are mixotrophs. have an outer structure reinforced by cellulose plates.
• Dinoflagellate blooms can create red tides.
• Ciliates use cilia to move and feed. most are predatory.
• Rhizarians use pseudopodia to move.
• Cerozoans are amoeboid and flagellated protists. common in moist/wet environments.
• Forams have a porous shell called a test, made of calcified organic matter. pseudopodia extend from the pore of the test.
• Archaeplastida is the third supergroups, contains red and green algae.
• green algae gave rise to plants.
• Red algae reproduce sexually with unflagellated gametes.
• Green Algae have chloroplasts similar to plants. They are found in freshwater and marine environments and have biflagellated gametes.
• Unikonta is the fourth supergroup. it is very diverse.
• Amoebozoans include many species of amoeba with tube or lobe shaped pseudopodia. slime molds are in this group.
• Opisthokonts is the most diverse group of eukaryotes.
• In aquatic communities, the main producers are photosynthetic prokaryotes and protists.
• protists represent 30% of the world's photosynthesis.
• Fungi and Plants only started to occupy the land within the last 500 million years.