Protists 2

Protists 2Laboratory 4BIOL 171Note: The PowerPoint in lab will be abridged so you have more time. Please take a few minutes to read this thoroughly. Thanks!

Lab Study E: AmoebozoansAmoeba proteusPseudopodia temporary extensions of amoeboid cells, function in moving and engulfing food

Slime Molds (Mycetozoa)Protists which use spores to reproduce

Heterotrophic requires carbon in organic form, cannot manufacture its own

Feed using phagocytosis

Suggests they descended from unicellular amoeba-like organisms

Two types: plasmodial and cellular (we will be observing plasmodial type today)

Physarum (slime mold)Plasmodial stage vegetative stage that consists of a multinucleate mass of protoplasm (no cell walls), feeds on bacteria as it creeps along the surface of moist logs or dead leaves

Fruiting bodies reproductive structures that produce spores

Physarum (plasmodial stage)

Is slime mold smarter than Japan's railway engineers? check it out!

Slime Mold Life Cycle

Psychedelic slime mold video:What is red algae?EukaryoticPhotosyntheticNOT plantsMost are aquatic

Lab Study F: Red Algae (Rhodophyta)Simplest is single celled, but most have a macroscopic, multicellular body formAutotrophic (photosynthetic) manufactures its own organic nutrients from inorganic carbon sourcesContain chlorophyll a and accessory pigments phycocyanin and phycoerythrinNot all are red! Many green, black, even blue, depending on the depth in the ocean they growLiving SpecimensPorphyridium

Preserved specimens

Chondrus crispusPorphyracoralline algaePorphyra life cycleboth sexual and asexual alternation of generations!

Coralline algae living rockExtremely important role in the ecology of coral reefs: sea urchins, fish, and mollusks eat them (herbivore enhancement).

Create microhabitats that protect invertebrates from predation.

Cell walls composed of calcium carbonate this allows it to fossilize

Economic importance: soil conditioners, food additive for livestock, water filtration, medical vermifuge (stopped late in 18th century), preparation of dental bone implants

Economic UsesAgar polysaccharide extracted from the cell wall of red algae, used to grow bacteria and fungiCarrageenan extracted from red algae cell walls, used to give the texture of thickness and richness to foods such as dairy drinks and soups.Porphyra (or nori) seaweed wrappers for sushi, billion-dollar industry!

Lab Study G: Green Algae (Chlorophyta)unicellular motile and non-motile, colonial, filamentous, and multicellular GREAT DIVERSITYLive primarily in freshwaterShare many characteristics with land plantsStorage of starch, presence of chlorophylls a and b, photosynthetic pathways, and organic compounds called flavonoidsMost botanists support the hypothesis that plants evolved from green algae

Living Specimens

ChlamydomonasPandorinaVolvoxPediastrumClosterium

VolvoxPreserved Specimens

UlvaCharaTable 4: Representative Green Algae (pg. 72)NameBody FormCharacteristicsSpirogyraFilamentousUlvaLeaf likeCharaBranchedChlamydomonasUnicellular flagellatePandorinaAggregateVolvoxColony (flagellate)PediastrumNon-motile colonyClosteriumNon-motile single celledStart filling out Table 5Comparison of protists studied last week and this week