Lab Report Oddities Gametic Life Cycle

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Lab 9- Algae Lab Report Oddities • Post lab 9, Question 4- – Only 2 kingdoms, not 3 • Pre Lab 10, Question 1 (255) – Answer for A in the blank for A below question Gametic Life Cycle Adult 2N- two copies of chromosomes Examples- Diatoms, Fucus 1 Zygotic Life Cycle Adult 1N- one copies of chromosomes 2N Zygote 1N Examples- Spirogyra, Chlamydomonas Sporic Life Cycle 2 Adults: 1N, 2N Examples- Laminaria, Ulva General Algae Characteristics • Autotrophic (mostly) – Chlorophyll a • Aquatic – Marine or Fresh Water • Phytoplankton or Microalgae- Unicellular • Macroalgae- multicellular • Sessile (generally) – Attached to a solid substrate (ex- rocks, trees) – Few found on slow moving mammal (sloths) 2 Kingdom Stramenopila • General Characteristics – Hairy Flagella (usually in reproductive phase) – Autotrophic OR Heterotrophic •Phylums – Oomycota – Chrysophyta – Diatom – Phaeophyta Kingdom Stramenopila Hyphae & Oogonia • Phylum Oomycota – Hetertrophic – Cellulose cell wall – Dioecious – Gametic meiosis zoosporangia Phylum Diatoms • Phytoplankton • Chlorophyll a & c, • Carotenoids • Silica cell walls • Reproduce asexually (mostly) • Gametic Meiosis during sexual reproduction 3 Phylum Diatoms Centric Pennate (Marine water) (fresh water) Not Diatoms Dinoflagellata Foraminifera Actinopoda (Radiolarian) Phylum Phaeophyta • Macroalgae • Chlorophyll a & c & Carotenoids • Store energy as laminarin and mannitol • Cellulose cell walls • Gametes: 2 flagella 4 Macroalgae Anatomy • Blade •Stipe • Air bladder – pneumatocyst • Holdfast Phylum Phaeophyta • Genus Laminaria • Sporic Meiosis • Similar life cycle to plants Phylum Phaeophyta • Genus Fucus • Gametic Meiosis • Called “Brown” algae, but isn’t necessarily 5 Macrocystis Kelp Forest California Kelp Forests Kingdom Plantae • Autotrophic • Chlorophyll a, b & Carotenoids • Starch as food reserve Phylum Chlorophyta • Genus Spirogyra • Unicellular Colonial • Zygotic Meiosis – Reproduction via conjugation 6 Phylum Chlorophyta • Genus Ulva • Macroalgae • Sporic Meoisis Phylum Chlorophyta • Genus Codium • Gametic Meiosis Phylum Chlorophyta • Genus Chlammydomonas • Freshwater phytoplankton • Glycoprotein cell wall • Zygotic meiosis 7 Phylum Chlorophyta • Genus Volvox • Colonial microalgae • Asexual and Sexual reproduction Phylum Rhodophyta • Macroalgae (mostly) • Autotrophic (mostly) • Chlorophyll a, phycobilins, carotenoids • Varied cell walls – Cellulose, –CaCO3, – Sulfacted galactons Phylum Rhodophyta • Forms- filamentous 8 Phylum Rhodophyta • Forms- filamentous highly branched Phylum Rhodophyta • Forms- foliacous Phylum Rhodophyta • Forms- encrusting coralline 9 Phylum Rhodophyta • Forms- jointed coralline 10.

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