Bio terms on protists

Alga

general term for any species of photosynthetic protist, including both unicellular and multicellular forms. These species are included in three eukaryote supergroup (Excavata, SAR, and Archaeplastida)

alternation of generations

a life cycle in which there is both a multicellular diploid form, the sporophyte, and a multicellular haploid form, the gametophyte; characteristics of plants and some algae

alveolate

one of the three major subgroups for which the SAR eukaryotic supergroup is named. This clade arose by secondary endosymbiosis, and its members have membrane-enclosed sacs (alveoli) located under the plasma membrane

amoeba

a protist characterized by the presence of pseudopodia

amoebozoan

a protist in a clade that includes many species with lobe- or tube-shaped peseudopodia

apicomplexan

group of alveolate protists, this clade includes many species that parasitize animals. Some species of this group cause human disease

Archaeplastida

one of the four supergroups of eukaryots proposed in a current hypothesis of the evolutionary history of eukaryotes.

blade

a leaflike structure of a seaweed that provides most of the surfce area for photosynthesis
The flattened portion of a typical leaf

brown alga

a multicellular, photosynthetic protist with a charecteristicic brown or olive color that results from cartenoids in its plastids. Most species are marine, and some have a plantlike body

cercozoan

an amoeboid or flagellated protist the feeds with threadlike pseudopodia

ciliate

type of protist that moves by means of cilia

conjugation

In prokaryotes, the direct transfer of DNA between 2 cells that are temporarily joined. When the 2 cells are members of different species, conjugation results in horizontal gene transfer. In ciliates, a sexual process in which 2 cells exchange haploid micronuclei but do not reproduce

Diatom

a photosynthetic protist in the stramenopile clade; these organisms have a unique glass-like wall made of silicon dioxide embedded in an organic matrix

Dinoflagellate

member of a group of mostly unicellular photosynthetic algae with 2 flagella situated in perpendicular grooves in cellulose plates covering the cell

Diplomonad

protist that has modified mitochondria called mitosomes, 2 equal-sized nuclei and multiple flagella

Endosymbiosis

a relationship between 2 species in which one organisms lives inside the cell or cells of another organism

Euglenid

a protist, such as Euglena or its relatives, characterized by an anterior pocket from which one or two flagella emerge

Euglenozoan

member of a diverse clade pf flagellated protists that includes predatory heterotrophs, photosynthetic autotrophs, and pathogenic parasites

Excavata

one of the four supergroups of eukaryotes proposed in a current hypothesis of the evolutionary history of eukaryotes. The organisms in this group have unique excavated feeding groove on one side of the cell body

Foraminiferan

an aquatic protist that secretes a hardened shell containing calcium carbonate extends pseudopodia through pores in the shell

golden algae

a biflagellated, photosynthetic protist names for its color, which results from its yellow and brown carotenoids

green algae

a photosynthetic protist, names for green chloroplasts that are similar in structure and pigment composition to the chloroplasts of plants. This group is a paraphyletic group; some members are closely related to plants than they are to other green algae

heteromorphic

referring to a condition in the life cycle of plants and certain algae in which the sporophyte and gametophyte generations differ in morphology

holdfast

a rootlike structure that anchors a seaweed

isomorphic

referring to alternating generations in plants and certain algae in which the sporophytes and gametophytes look alike, although they differ in chromosome number

kinetoplastid

a protist, such as trypanosome, that has a single large mitochondrion that houses an organized mass of DNA called a kinetoplast

mixotroph

an organism that is capable of both photosynthesis and heterotrophy

ocelloid

a unique, eye-like organelle found in a group of dinoflagellate protists, this complex, subcellular structure resembles the camera-like eye found in vertebrates and some molluscs

parabasalid

a protist, such as trichomonad, with modified mitochondria called hydrogenosomes

opisthokont

a member of an extremely diverse clade of eukaryotes that include fungi, animals, and several closely related group of protists

protist

an informal term applied to any eukaryotes that is not a plant, animal or fungus. Most of the species are unicellular, though some are colonial or multicellular

radiolarian

a protist, usually marine, with a shell generally made of silica and pseudopodia that radiate from the central body

red alga

a photosynthetic protist, names for its color, which results from a red pigment that masks the green of chlorophyll. Most species of this group are multicellular and marine

rhizarians

one of the three major subgroups for which the SAR eukaryotic group is named. Many species in this clade are amoebas characterized by threadlike pseudopodia

SAR

one of the four supergroups of eukaryotes proposed in a current hypothesis of the evolutionary history of eukaryotes. This supergroup contains a large extremely diverse collection of protists from three major subgroups: stramenopiles, alveolates, and rhizarians

secondary endosymbiosis

a process in eukaryotic evolution in which a heterotrophic eukaryotic cell engulfed a photosynthetic cell, which survived in a symbiotic relationship inside the heterotrophic cell

stipe

a stemlike structure of a seaweed

stramenopiles

one of the 3 major supergroups for which the SAR eukaryotic supergroup is named. This clade arose by secondary endosymbiosis and includes diatoms and brown algae

test

in foram protists, a porous shell that consists of a single piece of organic material hardened with calcium carbonate

Unikonta

one of the four supergroups of eukaryotes proposed in a current hypothesis of the evolutionary history of eukaryotes. This clade, which is supported by studies of myosin proteins and DNA, consists of amoebozoans and opisthokonts