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Single-celled or simple multicellular eukaryotic organisms that generally do not fit in any other kingdom

Binary fission

A form of reproduction where one protist cell splits into two identical cells

Multiple fission

A form of reproduction that produces more than two offspring


Where two individuals join and exchange genetic material stored in a small second nucleus


Large, rounded cytoplasmic extensions that function both in movement and feeding

Amoeboid movement

A method of movement involving the creation of pseudopodia


A protective covering used by some protists


Short, hairlike cytoplasmic projections that line the cell membrane


A clear, elastic layer of protien that surrounds the cell membrane of ciliates

Oral groove

A funnel-like depression in a pellicle, leads to the mouth pore

Mouth pore

Through which food is swept into a ciliate's gullet


Forms food vacuoles that move through a ciliate's cytoplasm

Anal pore

Expels undigested materials

Contractile vacuoles

Saclike organelles that expand to collect excess water and contract to squeeze the water out of the cell


Contains multiple copies of DNA that direct the cell's metabolism and development


Used in the exchange of genetic material during conjugation


Long, whiplike structures that are made up of microtubules and used for movement


Autotrophic protists that have chloroplasts and produce their food through photosynthesis


Single-celled gamete chambers in which an alga's gametes are formed


Free-living aquatic organisms that are at the base of most marine and freshwater food chains (most unicellular algae are these)


The plantlike body portion of a seaweed (usually has haploid cells)

Accessory pigments

Pigments that capture light energy and transfer it to chlorophyll


Unicellular protists that have double shells which contain silicon dioxide


The cell walls of diatoms which have two parts (like a box and lid) called valves made of silicon dioxide


The production of light by means of a chemical reaction in an organism

Red tide

Where dinoflagellate populations explode and they turn the water brownish red


Flagellated unicellular algae that are both animal-like and plantlike

Fruiting body

A funguslike, spore-bearing structure that funguslike protists produce

Water mold

A funguslike protist composed of branching filaments of cells

Plasmodial slime molds

A funguslike protist that has ameboid cells, flagellated cells, and a plasmodial feeding stage in its life cycle

Cellular slime molds

A funguslike protist that lives as an individual haploid amoeboid cell which gathers with other such cells in a pseudoplasmodium when nutrients are scarce

Algal blooms

A vast increase in the concentration of diatoms and other photosynthetic protists which can be caused by high water temperatures or nutrient concentrations


The movement toward or away from a chemical stimuluslike movement towards food or away from toxins


A polysccharide used in cosmetics, in various drugs, as a stabilizer in ice cream and salad dressings, in textiles, water-soluble medical dressings, for burns, and in inks, which is found in the cell walls of brown algae


A sticky substance sometimes found on the cell walls of red algae


A polysccaride used in scientific research to culture microbes, and also in canned food and bakery items that is found on the cell walls of red algae

Diatomaceous earth

A layer of material at the bottom of lakes and oceans formed when diatoms die and their shells accumulate, which is used in detergents, paint removers, toothpaste, and sometimes in in fliters, or as a natural insecticide


A disease caused by apicomplexians caracterized by severe chills, headache, fever, and fatigue


Plasmodium cells that enter a human's bloodstream with a mosquito bite and infect the liver


New Plasmodium cells formed in the liver and infect human red blood cells


Merozoites that develop the sexual forms of the parasite which are ingested by a mosquito when it bites an infected person and forms gametes


An illness caused by Giardia lamblia that is characterized by severe diarrhea and intestinal cramps


An illness caused mostly by Cryptosporidium parvum that is characterized by diarrhea and is resistant to chlorine disinfectants due to the protist's outer shell


A disease caused by Trichomonas vaginalis and is spread by sexual contact (one of the most commmon sexually transmitted diseases)

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