Protists

Synapomorphy

Shared derived characteristic.

Alveoli & Plastids

The two synapomorphies shared by members of the SAR clade.

Stramenopila, Alveolata, Rhizaria

The three protist supergroups in the SAR clade.

Ecological role, Habitat, Motility

Three ways we artificially group protists.

Excavata

Supergroup defined by having a feeding groove.

Strawmenopila

Supergroup defined by having straw-like hairs on the flagella.

Rhizaria

Supergroup defined by having hair-like pseudopodia.

Alveolata

Supergroup defined by having alveoli.

Amoebozoa

Supergroup of free-living heterotrophs who feed via pseudopods.

Opisthokonta

Supergroup defined by having a single posterior flagellum.

Archaeplastida - Plant-Related Algae

The supergroup that includes green & red algae.

Phaeophyceae

The subgroup of Strawmenopila that includes brown algae.

Bacillariophyceae

The subgroup of Strawmenopila that includes diatoms.

Oomycota

The fungus-like subgroup of Strawmenopila that possesses filamentous hyphae.

Metamonads

The subgroup of Excavata that includes parasites like Giardia.

Euglenoids

The subgroup of Excavata that has a light-sensitive eyespot. have flagellum chlorophyll. Apex predators

Kinetoplastida

The subgroup of Excavata that has special mitochondrial DNA in the form of a kinetoplast.

Ciliaphora

The subgroup of Alveolata that is defined by the presence of cilia, a cytosome, and a cytoproct.

Apicomplexa

The subgroup of Alveolata made up of multi-host animal parasites that have a special apical complex around an apical pore.

Dinozoa

The subgroup of Alveolata made up of marine plankton that possess a two-valved shell, 2 flagella, and chloroplasts with 4 membranes.

Radiolaria

The subgroup of Rhizaria that possesses a star-shaped silicate test (shell).

Foraminifera

The subgroup of Rhizaria that possesses a calcium carbonate test (shell).

Nuclearia

The subgroup of Opisthokonta that possesses filose pseudopodia.

Choanoflagellates

The subgroup of Opisthokonta that has a food-trapping collar and is believed to be closely related to metazoans (animals).

Rhodophyta

The subgroup of plant-related algae that includes red algae, lacks a flagella and is used in edible products.

Chlorophyta

The subgroup of plant-related algae that includes green algae and has both chlorophyl a and b.

Kinetoplast

A mass of DNA carried within a single, oversized mitochondrion associated with a subgroup of Excavata.

Phagocytosis

A type of feeding in which a food particle is surrounded by a vesicle of plasma membrane that pinches off within the cytoplasm. The food particle is then digested by enzymes intracellularly.

Alveoli

A series of saclike vesicles forming a nearly continuous layer beneath the cell membrane.

Plastid

A special type of organelle that can be photosynthetic or non-photosynthetic, believed to have been acquired through secondary or tertiary endosymbiosis.

Cilia

The many hair-like projections on the outside of cells that aid in movement.

Flagella

A long, whip-like filament that helps in cell motility.

Cytoproct

The specialized part of some cells that expels waste similar to an anus, typically associated with a subgroup of Alveolata.

Cytosome

A mouth-like organelle used to take in large food particles, typically associated with a subgroup of Alveolata.

Pseudopodia

A cellular protrusion of cytoplasm that some protists use to aid in moving and/or feeding. May be lobed, hair-like, or filose.

Secondary/Tertiary endosymbiosis

When a living cell engulfs another eukaryote cell that has already undergone primary endosymbiosis.

Algae/Plant-Like, Animal-Like (Protozoa), or Fungus-Like

Three types of ecological roles we can group protists into.

Plankton or Aquatic Substrate

Two types of habitats we can group protists by.

Flagellates, Ciliates, or Amoebae

Three types of motility we can group protists by.

Amoebae

The motility type group that is described as a crawling movement via pseudopodia.

Flagellates

The motility type group that involves using a whip-like appendage for movement.

Ciliates

The motility type group that involves using short, microscopic, hair-like structures for movement. This group is sometimes believed to be monophyletic.

Algae/Plant-Like Protists

The ecological role that involves photoautotrophic protists that produce O2 as a byproduct

Animal-Like Protists (Protozoans)

The ecological role that involves heterotrophic protists that feed by ingesting food items.

Fungus-Like Protists

The ecological role that involves heterotrophic protists that absorb nutrients from the environment, including water molds and slime molds.

Plankton

The habitat grouping that includes mostly unicellular protists that can be found in salt or freshwater. This can also include viruses, bacteria, small animals. These organisms are free-floating in their environment.

Aquatic Substrate

The habitat grouping that includes large photosynthetic protists (macroalgae), multicellular protists with differentiated cell types, and some very large single-cell protists. These organisms are found attached to surfaces in their environment.

Protist

1st Eukaryotes, Single celled Organisms