1. Kingdom Protista

2. General Characteristics
 Protists are very diverse and have few
traits in common
 Most are single-celled organisms, but
some are many cells, and others live in
colonies
 Some produce own food, others eat other
organisms or decaying matter
 Some can control own movement, others
cannot

3.  Characteristics that protists DO share:
 Eukaryotic(have a nucleus), but are less
complex than other eukaryotic organisms
 Do not have specialized tissues
 Members of the kingdom Protista are
related more by how they differ from
members of other kingdoms than by how
they are similar to other protists

4. zooflagellates
 Protists have many
different shapes
Pretzel slime
 Most scientists
mold
ulva
agree that fungi,
plants, and animals
evolved from early
protists
Paramecium

5. Protists and Food
 Protists can get food many ways:
 Can make own food
 Can eat other organisms
 Can eat parts or products of other organisms
 Can eat remains of other organisms
 Some use more than one way to get food
 Some produce food—they use chloroplasts
to produce food through photosynthesis

6.  Finding
Food
Heterotroph: organism that cannot
make own food
Some are decomposers—they get
energy by breaking down dead
organic matter

7. Asexual Reproduction
 Most protists
reproduce asexually
 Offspring come from
just one parent
 Binary fission: a
single-celled protist
divides into two cells
 Each new cell is a
single-celled protist

8. Sexual Reproduction
 Requires two parents
 Paramecium
sometimes reproduce
sexually by a process
called conjugation

9.  Algae
Kinds of Protists
 Allalgae have the
green pigment
chlorophyll, which is
used to make food
through
photosynthesis
 Almost all algae live in
water
 Free-floating, single-
celled algae are called
phytoplankton, which
produce much of the
world’s oxygen

10.  Amoebas
 Soft,jellylike
protozoans
 Found in fresh and salt
water, soil, and in
parasites
 Move with
pseudopodia, which
means “false feet”

11.  Ciliates
 Have hundreds of cilia—
tiny, hairlike structures
 Cilia move the protist
forward by beating back
and forth—sometimes up
to 60 times a second!
 Cilia are also used for
feeding—they move the
food towards the protist’s
food passageway
 Best known of ciliates is
the Paramecium

12.  Spore-Forming Protists
 Many spore-forming
protists are parasites
 They absorb nutrients from
their hosts
 No cilia or flagella, cannot
move on their own
 Have complicated life
cycles that usually
includes two or more hosts
 Example: protist that
causes malaria uses both
mosquitoes and humans
as hosts

13.  Slime Molds
 Heterotrophic and can
only move during certain
periods of life cycle
 Look like thin, colorful
globs of slime
 Use pseudopodia to
move and eat fungi and
yeast
 When environmental
conditions are stressful,
slime molds grow stalks
with knobs, which contain
spores

14.  Red Algae
 Most of world’s
seaweed is red algae
 Most live in tropical
oceans
 Usually less than 1 m
in length
 Contain chlorophyll,
but have red pigment
 Red pigment allows
them to absorb light
that filters deep into
ocean

15.  Brown algae
 Most seaweed in cool
climates are brown
algae
 Attach to rocks or form
large floating beds in
ocean waters
 Have chlorophyll and
yellow-brown pigment
 Many are very large—up
to 60 meters

16.  Green algae
 Most diverse of protist producers
 Green because chlorophyll is main pigment
 Most live in water or moist soil
 Others live in melting snow, on tree trunks, and
inside other organisms

17.  Diatoms
 Single-celled
 Found in salt and fresh water
 Get energy from photosynthesis
 Make up a large percentage of phytoplankton
 Cell walls contain a glasslike substance called silica