B From Bacteria to Plants B 2.1 Protists

Protists  A protist is a one- or many-celled organism that lives in moist or wet surroundings.  All protists have eukaryotic cells—cells – have nucleus  Protists usually reproduce asexually by cell division.  The result is two new cells that are genetically identical.

Protists  Asexual reproduction of many-celled protists occurs by regeneration.  Some protists are plantlike because, like plants, they contain the pigment chlorophyll in chloroplasts and can make their own food.  Plantlike protists are known as algae (AL jee) (singular, alga).

Protists  Dinoflagellates have two flagella. A flagellum (plural, flagella) is a long, thin, whiplike structure used for movement.  Protists that have characteristics of both plants and animals are known as the euglenoids (yoo GLEE noydz).

Protists Dinoflagelletes Euglenoid

Protists  When light is not present, Euglena can feed on bacteria and other protists.  One-celled, animal-like protists are known as protozoans.  These protists have cilia (SIH lee uh)— short, threadlike structures that extend from the cell membrane.

Protists Amoeba Paramecium

Protists  Some protozoans move through their environments and feed using temporary extensions of their cytoplasm called pseudopods

Protists