Red algae !
leafy red algae, nori(grown in a sheet, sushi wrap), dulse,!•
Red algae - food thickener (chondrus crispis) karogenen? !•
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-Trebouxia: symbiotic organism made up of fungi, often involves green algae !
!
Larger size and greater complexity evolved in green algae by 3 mechanisms:!
formation of colonies from individual cells (pediastrum(pond algae))!•
Formation of true multicellular bodies by cell division and differentiation (volvox and ulva(sea •
lettuce))!
Repeated division of nuclei with no cytoplasmic division (enormous cells)(caulerpa(intertidal •
chlorophyte))!
!
Life cycles in green algae:!
most chlorophytes have complex life cycles with both sexual and asexual reproductive stages!•
Nearly all species have bifilagellated gametes with cup-shaped chloroplasts !•
Alternation of generations has evolved in some chlorophytes, including ulva !•
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green algae very important in biotechnology !
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Supergroup of Eukaryotes: 28.5!
Amorphea (Unikonts) includes animals, fungi, and Amoebozoans.!•
The two major classes !◦
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Amoebozoans: are amoebas that have lobe - or tube shaped , rather than threadlike, •
pseudopodia!
They include tubulinids, slime molds, and entamoebas!◦
They move around hunting down bacteria, when they sense a particle, they flow their ◦
cytoplasm around the bacteria!
Tubulidids: diverse group of Amoebozoans with a lobe or tube shaped pseudopodia!•
Common unicellular protists in soil and in freshwater and marine environments!◦
Active predators of bacteria and other protists, others feed on detritus !◦
!
slime molds: were once thought to be fungi due to spore-producing fruiting bodies, but this •
resemblance is due to convergent evolution!
Slime molds have diverged into two lineages, plasmodial slime molds and cellular slime ◦
molds!
Plasmodial slime molds: often bright colored yellow and orange (dog vomit slime mold)!•
Form a large feeding mass called plasmodium that’s a single cell with many diploid nuclei ◦
undivided by plasma membranes!
Forms a fruiting body for sexual reproduction in unfavorable environmental conditions !◦
Cellular slime molds: form multicellular aggregates in which cells are separated by plasma •
membranes!
Cells feed individually, but can aggregate to form a fruiting body(coordinated movement and ◦
behavior)!
Complex and bizarre life cycle has provided insight into the evolution of multicellularity !◦
!
Entamoebas: all multicellular, parasites of all classes of vertebrates and some invertebrates !•
Humans are host to at least 6 species but only E. Histolytica is pathogenic !◦
E. Histo causes amoebic dysentery, the 3rd leading cause of death due to eukaryotic ◦
parasites !
