Unit 3 Ecosystems

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Unit 3 Ecosystems

• Chapter 6

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Part 1

• The Web Of Life p. 92
• Food Relationships p. 93
• Questions 3-9 in the book

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Define Ecosystem

• Ecosystem the network of relationships
  (interactions) among plants, animals and the
  non-living parts in an environment.

4
Differentiate the terms producers, consumer,
decomposers. P. 93
Other examples Grasses Trees shrubs Water
lilies Flowers Vegetables Fruits

• Producer a plant which can synthesize
  carbohydrates using carbon dioxide and the suns
  energy.
• Actually produce their own food and food for
  the rest of the ecosystem

5
Differentiate the terms producers, consumer,
decomposers. P. 93

• Consumers All those organisms that have to eat
  (consume) plants or animals to obtain their food.

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Types of consumers

• Primary Consumers Animals that eat producers.
  Also called 1st. order consumers. (Ex. Rabbit,
  squirrels, grouse, insects)
• Secondary Consumers Animals that eat primary
  consumers. Also called 2nd. order consumers.
  (fox, owl, mink )
• Tertiary Consumers Animals that eat secondary
  consumers. Also called 3rd. order consumers.
  (Wolf, coyote, hawk)

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8
Differentiate the terms producers, consumer,
decomposers. P. 94
Examples Worms Bacteria Fungi Protozoa

• Decomposers Simple organisms that obtain their
  food from dead/decaying organisms and wastes.

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Consumers, producers decomposers.

• Similarities
• All three are terms referring to the way
  organisms obtain food energy

• Differences
• The way they obtain food
• Producers make it,
• Consumers eat it,
• Decomposer feed on wastes dead material.

10
Differentiate the terms food chain food web.
P. 94

• Food chain linear sequence representing the
  nutrition of various species from the simplest
  plant to the top carnivore.

• Food web a series of interconnecting food
  chains in an ecosystem.

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Food Chain vs Food Web
12
Differentiate the terms food web food chain.
P. 94

• Similarity
• Both food chains and food webs show the flow of
  nutrients and energy in an ecosystem.

• Difference
• Food web is more complex
• Food web is composed of several food chains
• Food web is a more realistic picture of an
  ecosystem.

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Identify examples of producers consumersSee
Handout
Producers
Primary Consumers
Secondary Consumers
Tertiary Consumers
Decomposers
14
Give an example of a food chain from fig. 6.4.
P. 95
Tree ? insect ? insect eating bird ? hawk
Producer ? Primary consumer ? 2nd order consumer ? 3rd order consumer
Note The arrows indicate the flow of energy
nutrients from one level to the next
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Sample Food Chain
16
Draw an example of a food web containing humans.
P. 94
Hawk
Mosquito
Cow
fish
Man
Phytoplankton
Grass
Decomposer
17
Using figure 6.5 summarize the main energy flows
in an ecosystem p. 95

• Sun source of all ecosystem energy
• Producers make food via photosynthesis
• Consumers eat plants and other consumers to get
  energy
• Each time energy moves from one organism to
  another, energy leaves the system in the form of
  heat.
• Decomposers return nutrients to the soil but
  energy is not recycled. It is lost!

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Summary Energy Food Webs

• The ultimate source of energy (for most
  ecosystems) is the sun
• The ultimate fate of energy in ecosystems is for
  it to be lost as heat.
• Energy and nutrients are passed from organism to
  organism through the food chain as one organism
  eats another.
• Decomposers remove the last energy from the
  remains of organisms.
• Inorganic nutrients are cycled, energy is not.

• Question 14, 15 16 p. 98 make perfect review
  questions for the test.

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Energy flowanother look!!