Transcript PROTISTS - SharpSchool

PROTISTS
KINGDOMS
ARCHAEBACTERIA
EUBACTERIA
FUNGUS
– PROTISTS
ANIMAL
PLANT
WHAT IS A PROTIST?
• Organisms that share a lot of
characteristics with animals, plants and
fungus BUT they cannot be classified in
those Kingdoms because of some
fundamental differences.
• “junk drawer” Kingdom
– Very diverse group of organisms
• BUT, they do share some characteristics
– All are EUKARYOTIC
– All live in MOIST SURROUNDINGS
THERE ARE THREE TYPES
OF PROTISTS
• ANIMAL-LIKE
(ex. amoeba)
• FUNGUS-LIKE
(ex. water mold)
• PLANT-LIKE
(ex. Euglena)
ANIMAL-LIKE PROTISTS
• Called PROTOZOANS
• HETEROTROPHS
• Can move from place to
place to obtain food.
• UNI-CELLULAR
• Grouped into four
classes based on HOW
THEY MOVE
PROTOZOANS WITH
PSEUDOPODS (sarcodines)
What is a pseudopod?
-“false foot”; temporary
bulges of the cell
membrane that fill with
cytoplasm
May also have a contractile
vacuole
- collects extra water and
then expels it from the cell
Example – amoeba
AMOEBA
Amoebas are unicellular
protists that are able to
change their shape
constantly because their
PSEUDOPODS are
constantly changing.
Pseudopods also help
amoebas to get food by
ENGULFING and move
towards the light.
PROTOZOANS WITH CILIA
(ciliates)
What are cilia?- hair-like projections
on cells that move in a wave-like
motion.
More complex cells, Two nuclei (macro
and micro)
Oral groove – funnels food into the
cell
Two contractile vacuoles
Example - paramecium
Paramecium does not become
much larger than 0.3 mm
Paramecium caudatum
in conjugation
PROTOZOANS WITH FLAGELLA
(zooflagellates)
May have anywhere
from 1-8 flagella
Most live inside the
bodies of other
organisms
Trypanosoma – carried by
Tse Tse flies and infects red
blood cells causing the
sleeping sickness disease.
PROTOZOANS THAT ARE
PARASITES (sporozoans)
Feed on the cells and body fluids
of their hosts.
Most do not move, depends on its
host to move from place to
place; others ooze
Plasmodium – does not
move; is a parasite;
causes malaria
Infects a mosquito
which then infects a
human.
FUNGUS-LIKE PROTISTS
•
•
Alike fungus – are
HETEROTROPHS, have CELL
WALLS, and use SPORES to
reproduce
Unlike fungus – are able to MOVE at
some point in their lives
Video
FUNGUS-LIKE PROTISTS
• Live in moist places, the water, or dead and decaying
trees
• Brightly colored
TYPES OF FUNGUS-LIKE
PROTISTS
• Water molds
• Downey mildews
• Slime molds
Water molds can be parasitic
as seen here.
PLANT-LIKE PROTISTS
•
•
•
•
•
Called algae
All are AUTOTROPHS
Play an important role
as a food source in the
food chain
Provide most of the
atmosphere’s oxygen
Contain pigments
–
- Chemicals that
produce color
ALGAE CHARACTERISTICS
• Algae vary greatly in size
– Unicellular
– Multi-cellular
– Colonies
• Ex. Volvox
These Volvox live in colonies.
Even though they are each an
individual organism, some Volvox
are specialized to perform certain
functions for the colony like
respiration or reproduction.
Gametes
Daughter cells
Euglenoids
• Example: Euglena
• Green, uni-cellular
algae
• Eyespot near the
flagella senses
light.
EUGLENA
• Euglenoids, like
this Euglena, have
the ability to lose
their chloroplasts.
If you would keep
Euglena in the dark
they start feeding
on organic matter
and may loose their
pigment
Dinoflagellates
• Very colorful
• Some even fluoresce
and can seem to make
the ocean “glow” when
they are disturbed by
waves or passing
boats.
• Have two flagella and
move like spinning tops
Diatoms
• Found in two basic shapes:
– Centric – cylindrical
– Pennate – long, oval-shaped
• Diatoms are delicate
unicellular organisms that
have a yellow-brown
chloroplast that enables them
to photosynthesize.
• Their cell walls are made of
silica almost like a glass
house
• Layers of dead diatoms form
diatomaceous earth.
• Used to make polish, in pool
filters and as an insecticide
Red and Brown Algae
• Almost all red algae • Almost all brown algae
is seaweed.
is seaweed.
• Carrageenan is found in•
red algae and is used in
ice cream and hair
products.
Have lots of plant
characteristics like
holdfasts (roots), blades
(leaves) and stalks
(stems)
Red algal
bloom
Stalk
Green Algae
Ex. Spirogyra
In Spirogyra the
chloroplast runs
through the cell like a
helix.
Protists and Evolution
• Protozoans are believed to be the
evolutionary ancestors of all forms of animal
life.
• Green algae are believed to be the
evolutionary ancestors to all forms of plant
life.