q Review Notes

Eukaryotic photoautotrophs/heterotrophs; body plans range from unicellular to multicellular thalli.
Grouped into animal-like (protozoa), plant-like (algae), fungal-like (slime & water molds).
Nutrition: heterotrophy, autotrophy, or mixotrophy; motility common (flagella, gliding) except some sessile forms.
Key life-processes (circulation, respiration, excretion) largely by diffusion; reproduction asexual (fission, spores, fragmentation) or sexual (conjugation, gametes, alternation of generations).

Classic five-kingdom Protista splits into:
• Protozoa
• Algal Protists
• Fungus-like Protists
Expanded eukaryote lineages relevant to algae:
• Archezoa
• Euglenozoa
• Alveolata
• Stramenopila
• Rhodophyta
• Candidate: Chlorophyta, Slime molds

Unicellular, flexible pellicle beneath plasma membrane; one or two anterior flagella.
Pigments: chlorophyll a & b; storage product paramylon.
Mixotrophic; stigma + light detector enables phototaxis.
Osmoregulation via contractile vacuole; reproduction by longitudinal fission.

Unicellular alveolates with cellulose plates; two flagella in transverse cingulum & longitudinal sulcus → spinning motion.
Half are photo-/mixotrophs, rest heterotrophs; accessory pigments chlorophyll a & c, carotenoids.
Many produce toxins (e.g., saxitoxin → paralytic shellfish poisoning); cause algal blooms “red tides”.
Symbiotic zooxanthellae in corals; several bioluminescent genera.

Pigments: chlorophyll a & c plus fucoxanthin (golden color); reserve chrysolaminarin.
Mostly freshwater plankton; two unequal flagella; form silica-walled statospores.
Vaucheria: siphonous coenocytic filaments; both asexual & sexual (oogamy).

Frustule of silica (two thecae, epitheca & hypotheca); ornate pores.
Major marine & freshwater phytoplankton, significant global photosynthesis.
Asexual mitosis shrinks average cell size; size reset via sexual cycle.
Fossil frustules accumulate as diatomaceous earth (filters, abrasives, insulation).

Pigments chlorophyll a & b; starch in plastids; cellulose walls (most).
Habitats: fresh, marine, terrestrial, symbiotic (lichens).
Morphology spectrum: unicells (Chlamydomonas), colonies (Volvox), filaments (Spirogyra), sheets (Ulva), siphonous (Caulerpa), complex thalli (Chara).
Reproduction diverse: isogamy, anisogamy, oogamy; many alternations of generations.

Multicellular marine seaweeds/kelps; pigments chlorophyll a & c + fucoxanthin.
Thallus differentiated into holdfast, stipe, blades; pneumatocysts for buoyancy.
Storage polysaccharide laminarin; cell wall alginic acid (source of food thickeners & industrial algin).
Life cycle typically sporic with alternation of generations.

Mostly multicellular marine; pigments phycoerythrin & phycocyanin mask chlorophyll → red coloration, adaptive to deep water.
Reserve floridean starch; cell wall mucilages yield agar & carrageenan (food, pharma, industry).
Some calcified coralline forms aid reef building.
No flagellated stages; complex alternation of generations.

Green algae: biomass for biofuels, wastewater remediation, model organisms (Chlamydomonas), food (Ulva).
Brown algae: alginates (food stabilizers, cosmetics, textiles); giant kelp habitats.
Red algae: agar (microbiology media), carrageenan (emulsifier), edible nori; coralline species reinforce reefs.
Diatoms: diatomaceous earth (filters, abrasives); base of aquatic food webs.
Dinoflagellates: primary producers, but also harmful algal blooms impacting fisheries.

Pellicle, Paramylon, Mixotrophy, Statospore, Frustule, Pneumatocyst, Floridean starch, Algin, Agar, Carrageenan, Red tide.