Transcript Kingdom Protista - Cardinal Newman

Kingdom
Protista
General Characteristics
• Eukaryotic
• Unicellular (to colonial)
• Autotrophic or
Heterotrophic
• Appeared about 1.5 BYA
Classified into
3 main groups
1. Animal-like… heterotrophs capable of
locomotion
2. Plant-like… photosynthetic autotrophs
3. Fungus-like… decomposers that
reproduce by spores
Some protists may exhibit more than one
characteristic, such as...
….it is possible to be both animal-like and
plant-like.
Animal-like Protists
(26-2)
classified by
method of movement
Phylum Rhizopoda
(formerly Sarcodina) : ex. Amoeba
The Amoeba uses
pseudopodia for locomotion.
The Amoeba in 3D – notice the
pseudopods
Amoeba surround and engulf their food…
the process is called phagocytosis.
An Amoeba eating a Paramecium.
Ciliophora
• all use cilia for movement
• have many specialized structures, including
mouths, anal pores, contractile vacuoles,
and two nuclei (a large macronucleus and
small micronuclei)
• Ex. – Paramecium and Stentor
Phylum Ciliophora: ex. Paramecium
3D view – taken by a scanning
electron microscope
A closer look at the Cilia….
its means of locomotion
another Ciliate: Stentor
Phylum Zoomastigophora
• have flagella
• some species of
zooflagellates have
mutualistic
relationships
• ex.- Trichonympha
digests cellulose in
the guts of termites
Others are parasites, like Trypanosoma,
which causes
African Sleeping Sickness (coma).
Trypanosoma
Trypanosoma
Red Blood Cells
Trypanosoma
Tsetse Fly: carries
Trypanosoma to
humans; in other
words, it’s a Vector
White Blood Cell
Phylum Sporozoa
• are parasites
• have no means of locomotion
• form spores that are dispersed by
one or more hosts
• ex. Plasmodium, which causes
malaria
Portions of the Life Cycle of
Plasmodium vivax
Plasmodium
vivax
It’s Vector:
Anopheles
Mosquito
Red Blood Cells
Phylum Foraminifera
• have a protective shell or TEST, usually
made of calcium carbonate
• layers of tests can deposit on the ocean floor
– these can form limestone and chalk, like the
White Cliffs of Dover
– Some species of forams are good indicators of
oil deposits below
Cliffs of
Dover
Plant-like Protists
are classified by
COLOR
Phylum Chlorophyta
• have both chlorophyll a and b (so they are
green)
• have cellulose cell walls
• store carbohydrates as starch
• have many types of sexual reproduction
• exhibit many types of organization
--Are thought to be the ancestors of plants--
Variations in Sexual
Reproduction
• Isogamous= both sperm and egg
are motile and equal in size
• Anisogamous= both sperm and egg
are motile and differ in size
• Oogamous= large, nonmotile egg
and small, motile sperm
Variations in Sexual
Reproduction
Phylum Chlorophyta
organization
1. Unicellular
2. Filamentous
3. Colonial
4. Bi-layer
Unicellular Green Algae
Chlamydomonas
Chlamydomonas
Filamentous Green Algae
Spirogyra
has spiral-shaped chloroplasts
another filamentous Green Algae
Zygnema
2 Star-shaped chloroplasts per cells
a colonial Green Algae … Volvox
Mother colony with Daughter colonies
Mother Colony
Daughter Colony
a bi-layered Green Algae
Ulva (sea lettuce)
Harvesting Ulva
Phylum
Phaeophyta
•
•
•
•
brown algae
multicellular
flagellated sperm cells
Ex.: Fucus & Kelp
Phylum Pheaophyta:
Brown Algae… Laminaria.. Kelp ?
Air Bladders:
Used to take
blades to the
surface for PSN
Phylum Rhodophyta:
Red Algae
• are multicellular
• contain red
accessory
pigments called
phycobilins
• gametes do not
have flagella
Phylum Dinoflagellata
•
•
•
•
formerly known as Pyrrophyta or fire algae
have two flagella
some are bioluminescent, producing light
others produce nerve toxins
– dinoflagellates are collected and
concentrated in filter-feeding animals
– people who eat these animals become sick
Phylum Dinoflagellata
ex. Peridinium
Red Tideresults from a bloom of
Peridinium
Phylum Bacillariophyta:
Diatoms… have tests (shells) that contain
silica (SiO2), or glass
Diatom Strew
Diatoms - a SEM picture
Phylum Euglenophyta
• have one to three flagella at their leading
(apical) end
• have thin protein strips called pellicles
wrapped over their membranes
• have an eyespot that permits them to swim
toward light
• can become heterotrophic when there is no
light
Euglena
(arrow indicates anterior end)
The Euglena uses a flagella as a
means of locomotion.
Phylum Chrysophyta
• Are golden yellow
• Have one or two apical flagella
Phylum Acrasiomycota:
Cellular Slime Molds
• have both fungus and protist characteristics
• spores germinate into amoebas that feed on
bacteria
• When food is depleted, cyclic AMP is released,
causing amoebas to aggregate into one unit
• the crowd of amoebas form a slug that migrates
• cells from the slug form a stalk with a capsule,
which makes spores
• spores are released, and the cycle repeats
Acrasiomycota Life Cycle
http://sps.k12.ar.us/massengale/algal__fungal_protist_notes_b1.htm
Phylum Acrasiomycota
colony &
fruiting body
aggregating
amoebas
Phylum Myxomycota:
Plasmodial Slime Molds
• grow as a single, spreading mass or plasmodium
• feed on decaying vegetation
• when the environment becomes unfavorable (no
food or water), they form stalks and sporeproducing capsules
• haploid spores germinate into amoeboid or
flagellated cells
• these cells fuse to form a new diploid plasmodium
Myxomycota Life Cycle
Myxomycota
http://biodidac.bio.uottawa.ca/ftp/BIODIDAC/
Protista/Myxomyco/diagbw/Myxo005b.gif
Phylum Oomycota
• are parasitic and saprophytic
• form filaments, or hyphae (like fungi)
• secrete enzymes into surroundings & absorb
nutrients (like fungi)
• filaments lack septa or cross walls resulting
in many nuclei in a cell, they are coenocytic
• have cell walls made of cellulose, not chitin
Oomycota
Life Cycle
Examples:
• water molds
• downy mildews
• white rusts
http://agronomia.uchile.cl/webcursos/microbiologiagral/
pagina%20microbiologia1/micologia/fotos/oomycota.gif
http://protist.i.hosei.ac.jp/P
DB/Galleries/Klos/Bavaria/
Leptomitus_1.html
http://www.anselm.edu/hom
epage/jpitocch/genbios/28x2-PowderyMildew.jpg
Phylum Oomycota
• potatoes are native to North America
• they were introduced to Europe and
became a staple of the diet
• during the summer of 1846 most of the
potato crop was destroyed by
Phytophthora (an oomycota)
• nearly 1,000,000 Irish people died, and
1,500,000 emigrated to other countries,
like the U.S.