go to section: food for thought what do you do when you get hungry? you probably go in search of...
TRANSCRIPT
Go to Section:
Food for Thought• What do you do when you get hungry? You probably go
in search of food. Different organisms have different ways of obtaining the nutrients they need to live.
Section 20-1
Interest Grabber
1. How does an animal obtain food?
2. How does a plant obtain food?
3. Predict how a microorganism described as “plantlike” might behave.
Go to Section:
Section 20-1
Concept Map
are classified by
which includewhichwhich which
Protists
Animallike FunguslikePlantlike
ParasitesTake in food from the environment
Produce food by photosynthesis
Obtain food by external digestion
Decomposers
Go to Section:
On the Move• Think about the last time you watched a puppy at play, a fish in
an aquarium, or a squirrel in the park. They don’t stay still for long. How do they get where they are going?
Section 20-2
Interest Grabber
1. List five different ways in which animals can move from place to place.
2. What structures do these animals have that enable them to move?
3. What structures might a microorganism need in order to move?
Go to Section:
How Are Protists Classified
• Mainly by the way they move, how they obtain nutrients (animal-like, plant-like, fungus-like)– Movement: pseudopods, cilia, flagella– Obtaining Nutrients: autotrophic (plant-like)or
heterotrophic (animal-like, fungus- like)
Go to Section:
• 20–2 Animallike Protists: Protozoans
A. SarcodinesB. CiliatesC. Sporozoans- Animallike Protists and
Disease
1. Malaria2. Other Protistan DiseasesD- Zooflagellates
Section 20-2
Section Outline
Go to Section:
Life Processes and Lifestyle of a Sarcodines
• Cell Type: Eukaryotic, unicellular• Where they live: water environment
(freshwater and marine)• Mode of Nutrition: Heterotrophs, engulfs food• Reproduction: mainly asexually• Movement: Pseudopods via cytoplasmic
streaming• Examples: Ameoba
Go to Section:
Food vacuole
Nucleus
Contractile vacuole
Pseudopods
Section 20-2
Sarcodine Example: Amoeba-
Go to Section:
The Ameoba• Main Structures
• Pseudopods: “false feet”- uses them to move by cytoplasmic streaming. Also uses pseudopods to engulf food.
• Nucleus: control center, hereditary info• Food Vacuole: stores food and
nutrients
• Contractile vacuole: regulates the amount of water and pumps out excess water and wastes
Contractile vacuolePseudopods
Nucleus
Food vacuole
Go to Section:
Go to Section:
The Ciliates
• Cell Type: unicellular, eukaryotic• Where they live : Water environment• Movement: cilia – short hair-like projections, similar to
flagella that allow them to swim in their environment• Mode of Nutrition: heterotrophic- cilia sweeps in food
from their surroundings, or food can enter through an oral groove
• Reproduction: mainly asexual, can also by conjugation• Mostly free living – not parasitic• Examples: stentor, paramecium
Go to Section:
Anal pore
GulletOral groove
TrichocystsLysosomes
Food vacuoles
Contractile vacuole
Micronucleus
MacronucleusCilia
Section 20-2
Figure 20-5 A Ciliate
Go to Section:
• Cilia- hairlike projections that aid in movement of the organism
• Trichocysts- small bottle-shaped structures used for defense.
• Two nuclei- Micronucleus (cell divison) & Macronucleus
• Oral groove: collects and directs food into gullet
• Gullet- An indentation in one side of the organism that collects food.
• Contractile Vacuoles- specialized to collect water.
• Endoplasm: cytoplasm toward the middle of the cell
Go to Section:
The Blepharisma- Another ciliate
Go to Section:
• Paramecium life
Go to Section:
Phylum Sporozoa - Sporozoans
• Cell Type: eukaryotic and unicellular• Mode of Nutrition: heterotrophic (parasitic).
Complete part of their life processes within a host cell
• Movement: can not move by themselves. Rely on the host vector for transport, but can move within the vector
• Reproduction: asexually within the host cell cell
Go to Section:
Diseases that Sporozoans cause
• Malaria• Caused by the the sporozoan named
Plasmodium vivax• Plasmodium’s host is the mosquito• Can use chloroquinine to help treat it• Malaria Reading
Go to Section:
Section 20-2
Figure 20-7 The Life Cycle of Plasmodium
Go to Section:
Zooflagellates
• Cell Type: Unicellular, eukaryotic• Mode of Nutrition: Heterotrophic• Movement: flagella• Where they live: water and fluid environments• Reproduction: Asexual• Examples:
– Trypanosoma – Causes African Sleeping Sickness,– Trichonympha – found indigestive system of termites
Go to Section:
Go to Section:
Plant- like protists• Cell Type: some unicellular, some multicellular
(algae), eukaryotic• Mode of Nutrition: AUTOTROPHIC contains
chlorophyll to carry out photosynthesis. Some can be heterotrophic when light is not present
• Movement: some have flagella, some have cilia• Where they live: aquatic environments, soil,
some live in colonies• Reproduction: mainly asexual, but some sexual
(alternation of generations, spores)
Go to Section:
Types of Plant Like Protists
• Algae- are at the base of aquatic food chains (3 types- green, brown, and red)
• Euglenoids• Dinoflagellates• DiatomsExamples: volvox, spirogyra (spiral shaped
chloroplast), euglena
Go to Section:
Go to Section:
Interesting Facts About Plant Like Protists
• They produce much of the oxygen in aquatic environments
• Algae are protist not plants! Just because its green doesn’t mean that it’s a plant.
• Some plant like protists are found in toothpastes, pudding, salad dressing that are used as thickeners.
• Click the image to play the video segment.
Video
Algae
Go to Section:
Gullet
Chloroplast
NucleusEyespotFlagella
Section 20-3
Euglena
Carbohydrate storage bodies
Pellicle
Contractile vacuole
Go to Section:
• 2 Flagella• No Cell Wall• Red Eye Spot to detect light• Contains chloplas to carry out photosynthesis• Autotrophs and Heterotrophs when sun is not
available• Pellicle: stiff outer membrane
Go to Section:
• 2 Flagella• No Cell Wall• Red Eye Spot to detect
light• Autotrophs and
Heterotrophs when sun is not available
• Pellicle: stiff outer membrane
Eyespot
Pellicle
Go to Section:
Important euglena structures• Pellicle- stiff outer
membrane • Contractile vacuole-
regulates and pumps excess water and wastes
• Chloroplast- site of photosynthetic activity
• Flagella- movement• Eyespot- helps to detect the
light• Nucleus- hereditary, genetic
material
Go to Section:
Fungus-like Protists• Cell Type: eukaryotic, unicellular majority of time• Mode of Nutrition: heterotrophic, decomposers • Reproduction: asexual and sexual stages by spores• Where they live: water or moist environments, decaying
plants and trees• Movement: can all move at some point, some have
pseudopods (slime mold)• Commonly called: slime molds and water molds. Water
molds responsible for the Irish Great Potato Famine, can destroy crops
• Examples: Acrasiomycota - Cellular Slime Mold, Myxomycota - Acellular Slime Mold, Oomycetes- Water mold
Go to Section:
• Water MoldAnd slime mold
• Links on funguslike protists• Interactive test
• Articles on protists • Articles on protozoans
• For links on protists, go to www.SciLinks.org and enter the Web Code as follows: cbn-6201.
• For links on algae, go to www.SciLinks.org and enter the Web Codeas follows: cbn-6204.
Go Online