kingdom protista “the very first”
DESCRIPTION
Kingdom Protista “the very first”. any organism that is not a plant, animal, fungus, or prokaryote (bacteria) Eukaryotes 1.5 billion years ago Classified by nutrition mode Animal like, Plant like, or Fungus like. Symbiosis. - PowerPoint PPT PresentationTRANSCRIPT
Kingdom Protista “the very first” any organism that is not a plant, animal,
fungus, or prokaryote (bacteria) Eukaryotes 1.5 billion years ago Classified by nutrition mode Animal like, Plant like, or Fungus like
Symbiosis Relationship between organisms; one organism
lives in or on the other Organisms involved in relationship are called
symbionts 3 Types:
Mutualism: both symbionts benefit Commensalism: one symbiont benefits; other is
unaffected Parasitism: one symbiont benefits; other is harmed
Vectors Mechanically transfer parasite into host Exs: tse-tse fly; female Anopheles
mosquito Carriers
Unaffected by disease
A) Animal-like Protists: Protozoans
Protozoa-”First animals”
Heterotrophs Four phyla based
on how they move Unicellular
1) Phylum Zoomastigina: Zooflagellates flagella Absorb food through
their cell membranes Most reproduce
asexually- binary fission
Live in lakes and streams or bodies of other organisms
Diseases (African Sleeping Sickness)
Trypanosomiasis Trypanosoma – Tsetse Fly Chills, rashes, nerve cell damage, coma
Termites and Trichonympha Symbiotic (lives off food from termite) Lives in termite gut Contains cellulase that digests wood
2) Phylum Sarcodina: Sarcodines Pseudopods “false foot” – cytoplasmic projections for
eating and movement Best known sarcodine - Amoeba Amoeboid movement Contractile and Food Vacuoles Binary Fission Foraminiferans – secrete calcium carbonate shells (chalk),
accumulates on bottom of ocean.
Contractile Vacuole (pump water)
Nucleus
Food Vacuole (store food)
Pseudopods
ex. AMOEBA
Amebic Dysentery (Amebiasis)
• Entamoeba-parasite spread by contaminated drinking water from poor sanitation
• Severe diarrhea, attacks intestines, bleeding• Boiling water or iodine kills parasite
3) Phylum Ciliophora: Ciliates Cilia – used for feeding and movement
Short, hair-like projections Binary Fission and Conjugation (stress) Best known ciliate – paramecium Freshwater and saltwater Trichocysts-stiff projections for defense of
paramecium
Internal Anatomy Two nuclei Macronucleus
respiration, protein synthesis, and digestion. Micronucleus
conjugation and contains a reserve copy of genes.
Anal pore
GulletOral grooveTrichocysts
Lysosomes
Food vacuoles
Contractile vacuole
Micronucleus(conjugation) Macronucleus
Cilia
Figure 20-5 : ex. Paramecium
Nutrition The cilia move food into the oral groove which
leads to the gullet. The food is forced into food vacuoles Lysosomes break down the food with enzymes Undigested food is removed through the anal
pore Contractile Vacuoles pump water in and out to
maintain homeostasis
Macronucleus
Micronucleus
Conjugation
MEIOSIS Exchange ofmicronuclei
Macronucleidisintegrate
New macronuclei
form
Genetically identical
paramecium form
*note: conjugation is a sexual process but NOT a form of sexual reproduction b/c no new individuals are formed. However, new combinations of genetic information are produced.
4) Phylum Sporozoa: Sporozoans Parasitic protists
Parasites of many different organisms, including worms, fish, birds, and humans.
Many protists cause serious disease Cannot move independently Reproduce using sporozoites A sporozoite can attach itself to a host and
lives as a parasite.
Diseases Malaria- sporozoan Plasmodium Saliva of the female Anopheles mosquito Sporozoites enter the bloodstream and the
parasite infects the liver cells and red blood cells. Red cells burst and release toxins into the
bloodstream 2 million people die each year from malaria
800 million infected worldwide
B) Plant-like Protists: Unicellular Algae
Base of the food chain “phytoplankton” photosynthetic pigments Autotrophs 4 phyla based on the type of pigments they
contain
1) Phylum Euglenophyta: Euglenophytes two flagella Lack a cell wall Cell membrane called a pellicle Chloroplasts – photosynthetic Heterotrophic if no sunlight available Eyespot – finds sunlight Pellicle – tough and flexible
Gullet
Chloroplast
NucleusEyespotFlagella
Euglena Fig. 20-10Carbohydrate storage bodies
Pellicle
Contractile vacuole
2) Phylum Pyrrophyta “fire plants”: Dinoflagellates 50% photosynthetic 50% heterotrophs 2 flagella Plates made of
cellulose for protection
Many are bioluminescent
Algal Blooms• Protists grow rapidly in areas rich in
sewage• Excessive waste leads to excessive
growth protists and algae• Deplete nutrients from water• Dead algae rob water of its oxygen
• Dead marine life
Red Tide Water appears red due
to “Algal Bloom” Certain species of
dinos produce toxin that is taken in by shellfish
Ban on shellfish Can cause PSP
Red Tide off the coast of CA
Paralytic Shellfish Poisoning PSP is caused by a dino species that
produces a toxin that is taken up by mollusks.
Eating these infected shellfish can cause serious illness, paralysis, or death
3) Phylum Chrysophyta: Chrysophytes Yellow-green and golden-brown algae Gold-colored chloroplasts Pectin cell wall Store food in the form of oil
4) Phylum Bacillariophyta: Diatoms Cell walls – silicon
(glass) Cannot decompose
C) Plantlike Protists: Multicellular Algae = Seaweed
Red, Brown, and Green
1) Phylum Rhodophyta: Red Algae
Contain Chlorophyll a and Phycobilins Absorb blue light – 260 meters, very deep Important role in forming coral reefs Chondrus crispus- Irish moss
Chondrus crispus – Irish Moss
2) Phylum Phaeophyta: Brown Algae
Chlorophyll a and c, Fucoxanthin Holdfast, Stipe, Blades, Bladders
(Fig 20-15) Fucus- Rockweed Sargassum Kelp
Kelp
Rockweed
Fucus : Rockweed
Sargassum
Blade
Stipe
Hold Fast
3) Phylum Chlorophyta: Green Algae
Cellulose in their cell walls Chlorophyll a & b Stores food as starch Very similar to plants
Unicellular Green Algae Chlamydomonas Lives in ponds, wet
soil, etc.
Colonial Green Algae Spirogyra Volvox – connected strands of cytoplasm,
coordinated flagella movement
Multicellular Green Algae
Sea lettuce- Ulva
Importance of Algae •Base of the food chain•Kelp forests – habitats•50% of oxygen production•Used in many foods and products