Diversity and Evolution Flashcards
Polyphyletic
Group composed of a collection of organisms but most recent common ancestor not included
Paraphyletic
Group composed of a collection of organisms including most recent common ancestor but not all descendants
Definition of algae
Plastid-bearing protists - predominantly aquatic, has a plastid (chloroplast), performs photosynthesis
Thallophytes
Plants without rooms, stems, leaves, with chlorophyll as primary photosynthetic pigment
Phytoplankton
Functional group of single-celled organisms with capacity for photosynthesis, adapted to live in open water
Seaweeds
Informal group of macroscopic, multicellular algae from multiple taxa
Periphyton
Complex mix of algae, cyanobacteria, heterotrophic microbes, and detritus attached to submerged surfaces in freshwater habitats (biofilm)
Epilimnion
Top layer in thermally stratified lakes
Hypolimnion
Bottom layer in thermally stratified lakes
Stromatolites
Layered sedimentary formations created by mainly cyanobacteria in shallow waters, often found in extreme environments
Axoneme
Microtubule-based cytoskeletal structure that forms core of flagellum/cilium
Basal body
Where flagellum attaches to cell
Nexin link
Protein linking microtubule complexes that converts action of dynein into bending
Mucilage
Excretion external to cell wall that most algae produce
Coccolithophores
Unicellular marine algae in the phylum Haptophyta
Coccoliths
Overlapping plates of transparent calcium carbonate
Frustules
Diatom-specific porous cell wall of silicon dioxide embedded in a polysaccharide matrix
Raphe
Slit along length of frustule that excretes mucilage
Eyespot
Specialized structure within chloroplast that can detect intensity and direction of light and send signals to flagella
Pyrenoid
Specialized structure within chloroplast containing large quantities of Rubisco, serves as carbon concentration mechanism
Mixotrophic
Can combine autotrophic and heterotrophic nutritional modes according to metabolic needs and environment
Photoheterotroph
Algae with a chloroplast that depends on light but grows slowly without prey
Leucoplast
Underdeveloped plastid that functions as starch storage
Chemoheterotroph
Algae that uses dissolved carbon, does not need light
Primary endosymbiosis
Process that involves engulfment of a prokaryote by another cell
Group containing green plants, red algae, and Glaucophytes
Archaeplastida
Secondary endosymbiosis
Eukaryotic cell engulfs cell that has already undergone primary endosymbiosis
Model for evolution of endosymbiosis
Paulinella spp.
Chromatophore
Reduced photosynthetic organelle in Paulinella
Primary modern proponent for significance of endosymbiosis
Lynn Margulis
