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Decomposers Everywhere! Study Guide, 1
Eye of the Cyclops
Series Teaching Guides
Decomposers Everywhere!
Copyright 2000 BioMEDIA ASSOCIATES
Environment: a freshwater pond
Habitat: the open water
Permission is given to copy or print this guide for use within institutions that have purchased the Decomposers
Everywhere! video program. All images are property of BioMEDIA ASSOCIATES and cannot be resold without
permission.
Contents of this guide...
• About Decomposers Everywhere!
• Teacher’s guide with national science standards
• Student Research Problems
• Decomposers Gallery
page 3...
page 4...
page 7...
page 8...
In this episode...
Settling their craft into the bottom, the Cyclops’ crew discover that the bottom ooze is populated
by bacteria, thousands per cubic millimeter. They capture one and investigate the chemical
methods it uses to decompose organic material—digestive enzymes secreted through tiny pores
in its outer covering. The debriefing discussion shows the many kinds of living bacteria that
carry out decomposition—rods, a variety of spiral shaped cells with flagellar propellers at each
end, and spirochetes—an unforgettable visual introduction to living bacteria.
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Decomposers Everywhere! Study Guide, 2
Cyclops
Vehicle Dimensions
LENGTH
BEAM
1 mm
.65 mm
Vehicle Mission
Maximum speed
Maximum depth
Mission duration
10 centimeters per minute
2.5 meters
50 days
The microsubmersible Cyclops is designed for extended exploration of
freshwater ponds and streams. The vehicle carries a crew of four. There are
two onboard auxilary craft: a diving bell and a terrestrial crawler (disassembled). Imagine what the pond environment looks like to these explorers
(only 50 microns tall). What unique problems might the crew encounter?
How would they acquire building materials, such as glass? Where would
they find fuel and oxygen?
airlock
engine room
observation/pilothouse
diving room
diving bell
laboratory
bunkhouse
emergency escape hatch
storage modules
grabber claws
Eye of the Cyclops
vehicles are designed by
Eric Robert Russell/Castle
Builders Entertainment
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Decomposers Everywhere! Study Guide, 3
About the organisms
POND BACTERIA
The layer of loose organic material covering a pond bottom is swarming with life. This
bottom ooze is where organic material is broken down and its vital elements recycled. The
agents responsible are decomposer bacteria, including some of the largest and most interesting representatives of these tiny cells.
Live bacteria from pond bottom sample.
The kinds of bacteria are often thought of as the familiar spheres, rods and spiral bacteria
seen in medical text books. However, a pinch of soil will contain millions of bacterial cells
representing hundreds and possibly thousands of different kinds. Very little is known
about these “wild” bacteria, and only a small percentage have been cultured and named.
With enough effort, it’s likely that several million different kinds could be described living
in soil and in wetlands. Also each species of animal, plant, and fungi has its own types of
bacteria. Just think of how that increases the number of bacteria species.
Because bacteria can have many generations a day, their evolution into distinct new types
can occur quite rapidly. Disease causing bacteria, for example, quickly evolve antibiotic
resistant strains, keeping medical science on a constant search for new antibiotics.
Decomposer bacteria secrete digestive enzymes into their environment. The enzymes
attack dead organic material breaking it down into simple building-block molecules.
Bacteria absorb these building blocks and use them for energy and also to build new bacterial proteins, fats, carbohydrates and nucleic acids.
Bacteria become food for bacteria feeding protists such as Paramecium, beginning food
chains based on decomposition.
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Decomposers Everywhere! Study Guide, 4
Teacher’s Guide
Use the Decomposers Everywhere video to excite your students with the idea of visiting a local pond or
wetland in order to discover and study naturally occurring bacteria, and through these activities to better
understand the ecology of these habitats.
Relevant National Science Education Standards Grades 5-8
Reproduction and Heredity
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Reproduction is a characteristic of all living systems; because no individual organism lives forever,
reproduction is essential to the continuation of every species. Some organisms reproduce asexually.
Other organisms reproduce sexually.
Bacteria reproduce by simple division, and are the most rapid reproducers found in nature. They also come
together and exchange genetic material, one of the qualities of sexual reproduction.
Regulation and Behavior
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Behavior is one kind of response an organism can make to an internal or environmental stimulus. A
behavioral response requires coordination and communication at many levels, including cells, organ
systems, and whole organisms. Behavioral response is a set of actions determined in part by heredity
and in part from experience.
Motile bacteria respond to chemical signals that keep them near their food supply.
Populations and Ecosystems
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Populations of organisms can be categorized by the function they serve in an ecosystem. Plants and
some micro-organisms are producers—they make their own food. All animals, including humans, are
consumers, which obtain food by eating other organisms. Decomposers, primarily bacteria and fungi,
are consumers that use waste materials and dead organisms for food. Food webs identify the relationships among producers, consumers, and decomposers in an ecosystem.
This is a main theme of the video program Decomposers Everywhere.
Diversity and Adaptations of Organisms grades 5-8
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Biological evolution accounts for the diversity of species developed through gradual processes over
many generations. Species acquire many of their unique characteristics through biological adaptation,
which involves the selection of naturally occurring variations in populations. Biological adaptations
include changes in structures, behaviors, or physiology that enhance survival and reproductive
success in a particular environment.
What adaptations (structures or behaviors that function to promote the organism’s survival ) can be listed for
the bacteria found by Cyclops?
Correlation with Middle School Science Text Books
Visit our website, www.eBioMEDIA.com to consult a newly updated list of text books that dovetail with Eye
of the Cyclops. With texts being reprinted constantly, this online list will help you design effective science
lessons that mesh with the books you’re using in the classroom.
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Decomposers Everywhere! Study Guide, 5
Concept Words used in this Program
Habitat: The place where an organism lives.
Microorganisms: Small living things that can only be adequately
observed with the aid of magnification.
Macroorganisms: Organisms that can seen without magnification
(although enlargement may be needed to see their structures)
Bacterium: A simple single celled organisms lacking nucleus and
organelles.
Cyanobacteria: A branch of Bacteria composed of species that carry
out water-splitting photosynthesis.
Enzymes: Large proteins that act as catalysts to promote specific
chemical reactions.
Digestion: Enzymatic breakdown of large organic molecules into their
molecular building blocks.
Fermentation: A type of anaerobic (no oxygen required) respiration
in which sugar molecules are broken down into carbon dioxide and two
carbon compounds such as alcohol.
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Decomposers Everywhere! Study Guide, 6
Programs in the Eye of the Cyclops series
Plankton Play (15 minutes)
Cyclops and its intrepid crew of explorers dive into open water where they encounter the denizens
of the plankton: micro-crustaceans, insects, rotifers and protists, all showing unique adaptations for
open water life.
Decomposers Everywhere (15 minutes)
Settling their craft into the bottom, the micronauts discover that the bottom ooze is populated by
bacteria, the microbes that decompose and recycle organic materials—an unforgettable visual introduction to living bacteria.
Food Chains Begin with Photosynthesis (15 minutes)
In this episode, a single algae cell is rescued and its green secrets revealed through experiments
performed on board the Cyclops. They discover how algae start food chains that ultimately sustains
the fish, birds, amphibians and mammals living in and around the pond.
Protozoans and Algae (15 minutes)
Cruising through the weedy shallows, the crew is amazed at the diversity of protozoans swimming
by the observation ports. They discovery how these complex single cells feed, reproduce and escape.
Predators of the Shallows (15 minutes)
While engrossed in observing the food capturing and feeding methods used by predatory flatworms,
the Cyclops crew becomes trapped by the tentacles of Hydra where they receive a visible lesson in the
process of digestion.
White Water Adventure (15 minutes)
Trying to return to duck weed base, the Cyclops is channeled into the pond outlet, where they tumble
into a rapidly flowing stream and discover a world of aquatic insects adapted for life in flowing
water.
Discovering a Forest Microcosm (15 minutes)
Washed onto a sand bar, the Cyclops crew assembles their terra-rover and discovers a world dominated by mites, roundworms, tiny insects, bacteria and fungi—creating a forest floor ecosystem on
which the trees depend.
Backyard Biodiversity (15 minutes)
The micronauts discover that gardens support an amazing community of small life including butterflies and their larva, pollinating insects, herbivores, predators, scavengers and earthworms that
constantly process the soil.
Visit Cyclops on the World Wide Web
Check www.eBiomedia.com for an ongoing story of the crew’s biological explorations and more tips on how
to study the fascinating organisms they encounter. Post your research results there and see what other
students are discovering.
Eye of the Cyclops is produced by BioMEDIA ASSOCIATES
in association with Castle Builders Entertainment.
Order Eye of the Cyclops from www.ebiomedia.com
eBioMEDIA • P.O. Box 1234 • Beaufort, SC • 29901-1234
ORDER/INFO: (877) 661-5355/(843) 470-0236
FAX: (843) 470-0237
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Decomposers Everywhere! Study Guide, 7
Student Research
To study bacteria in their natural environment,
create a “stinking brew culture.”
Place a handful of decomposing leaves into a jar and cover with aquarium or
pond water. This is one of the best ways to culture vast numbers of very
large bacteria, including many kinds that are easily observed with a student
microscope. Text books often suggest that the only way to see bacteria is to
kill and stain them on a microscope slide. This is the correct approach for
bacteria that cause disease, but when used to study decomposer bacteria, it
misses the most interesting aspects of these amazing microbes—their behavior.
TIP: When viewing living unstained bacteria close your microscope’s
iris diaphragm more than the normal amount in order to increase
contrast. If your microscope has diaphragm holes, try the smallest
hole. The increase in contrast is at the expense of resolution, but this
trade-off is often required when viewing clear, unstained subjects.
Also, see Guide to Microlifefor a method of adapting a laboratory microscope for “dark-field” viewing, a very effective way to observe bacteria and other transparent cells.
And you thought rabbits were rapid multipliers—Here is an interesting mental experiment: Begin with a bacillus (a rod shaped
bacterium) 10 micrometers in length and give it an unlimited food source
and optimum temperature so that it can divide every 30 minutes. Calculate
how long it would take for a string of these rapidly multiplying rods to reach
around the world.
They wiggle, they jiggle, they slide and they glide. Check it out.
Bacteria from the natural environment show a variety of shapes including
long filaments, gliding strands, chains and long and short rods with all degrees of twists. See how many different body forms you can find in your
“stinking brew” culture. Compare their movements. What survival advantages might be conferred by a bacterium’s shape and its motions?
Who are the simplest cells of all. Observe and compare.
Based on your own observations make a list of the differences between bacteria and protozoans.
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Decomposers Everywhere! Study Guide, 8
Decomposers Gallery
Bacteria • Fungi • Protists
Decide which organisms are bacteria, fungi, or protists. Which organism is not a
decomposer. Answers will be found in the gallery section of our web site.
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All images copyright 2000 BioMEDIA ASSOCIATES, Photography by Bruce J. Russell