Protists Terms to Know

Primary Endosymbiosis

the evolutionary process where a eukaryotic cell engulfs and keeps a prokaryotic cell, resulting in a permanent symbiotic relationship

Secondary Endosymbiosis

when a eukaryotic cell engulfs a cell that has already undergone primary endosymbiosis

Symbiosis

interaction between two different organisms living in close physical association, typically to the advantage of both

Mutualism

a type of symbiotic relationship where two or more species benefit from their interaction

Commensalism

an association between two organisms in which one benefits and the other derives neither benefit nor harm

Parasitism

the practice of living as a parasite in or on another organism

Autotrophic

an organism that makes its own food

Heterotrophic

getting its food from other plants or animals, or relating to such living things

Mixotrohpic

an organism that uses a mix of different sources of energy and carbon

Binary Fusion

a form of asexual reproduction where a single cell divides into two genetically identical daughter cells

Conjugation

the temporary union of two bacteria or unicellular organisms for the exchange of genetic material

Plankton

the small and microscopic organisms drifting or floating in the sea or fresh water

Phytoplankton

plankton consisting of microscopic plants.

Zooplankton

plankton consisting of small animals and the immature stages of larger animals.

Plastid

any of a class of small organelles, such as chloroplasts, in the cytoplasm of plant cells, containing pigment or food.

Chloroplast

a plastid that contains chlorophyll and in which photosynthesis takes place.

Mitochondria

an organelle found in large numbers in most cells, in which the biochemical processes of respiration and energy production occur. It has a double membrane, the inner layer being folded inward to form layers (cristae).

Mitosome

mitochondrion-related organelles found in a range of unicellular eukaryotic organisms that inhabit oxygen-poor environments

Hydrogenosome

specialized organelles found in certain anaerobic or microaerobic eukaryotes, like anaerobic ciliates, trichomonads, and fungi

Alveoli

tiny, balloon-shaped air sacs located at the end of the respiratory system's airways

Cilia

a specialized type of nucleus found in dinoflagellates, a group of eukaryotic algae

Dinokaryon

a specialized type of nucleus found in dinoflagellates, a group of eukaryotic algae

Theca

a case, covering, or sheath

Red Tides

a discoloration of seawater caused by a bloom of toxic red dinoflagellates.

Bioluminescent

the biochemical emission of light by living organisms such as fireflies and deep-sea fishes

Frustule

the silicified cell wall of a diatom, consisting of two valves or overlapping halves.

Flagella

a slender threadlike structure, especially a microscopic appendage that enables many protozoa, bacteria, spermatozoa, etc. to swim.

Heterokont

any organism that possesses two flagella of unequal length

Phycoerythrin

any of a group of red photosynthetic pigments present in red algae and some cyanobacteria

Chlorophylls A and B

the primary photosynthetic pigment found in plants, algae, and some bacteria

Pellicle

a thin, membranous layer, or film, found in various contexts

Stigma

the pollen-receptive surface of a flower's pistil, which is the female reproductive part

Zooxanthellae

single-celled photosynthetic organisms that are able to live in symbiosis with diverse marine invertebrates

Cytostome

a specialized cellular structure, specifically the "mouth" or opening of a protozoan cell

Pseudopodia

temporary, arm-like projections of a cell's cytoplasm that are used for locomotion and feeding

Phagocytosis

a process where a cell engulfs and digests particles like bacteria or cellular debri

Plasmodium

a form within the life cycle of some simple organisms such as slime molds, typically consisting of a mass of naked protoplasm containing many nuclei.

Chemotaxis

movement of a motile cell or organism, or part of one, in a direction corresponding to a gradient of increasing or decreasing concentration of a particular substance.

Zoospore

a spore of certain algae, fungi, and protozoans, capable of swimming by means of a flagellum

Sorocarp

the fruiting body characteristic of certain cellular slime molds

Coenocytic

a multinucleate cell or structure where multiple nuclei are contained within a single cytoplasm and cell wall, without individual cell divisions

Oogonia

the female sex organ of certain algae and fungi, typically a rounded cell or sac containing one or more oospheres

Antheridia

the male sex organ of algae, mosses, ferns, fungi, and other nonflowering plants.

Auxospore

a reproductive cell that is produced by a diatom cell that has reached the minimum size for a species