What is an ecosystem? An ecosystem refers to all the animals

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What is an ecosystem?

• An ecosystem refers to all the animals and plants
  found in one place, and the way they all live
  together.
• Different plants and animals live in different
  ecosystems.
• Different ecosystems can be close together.
• Some animals belong to several ecosystems.

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What is an environment?

• Everything that affects an animal makes up its
  environment - where it lives, the weather and all
  the living things it comes into contact with.
• Every living thing, including people, has an
  effect upon the environment.

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Animal Adaptation

• All living things have to be suited to their
  environment if they are to survive.
• Fish have streamlined bodies, fins and specially
  shaped tails to help them move quickly and easily
  through the water.
• Squirrels have sharp, strong claws for gripping
  tree trunks and branches and strong teeth for
  eating nuts.

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How is the seal adapted to its environment?
Streamlined shape.
Forward-facing eyes for clear vision ahead.
Strong teeth to catch fish.
Flippers to help it swim.
Thick layer of body fat to keep it warm.
Hind legs have evolved into a a strong
rudder-like tail.
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Homes and Habitats

• The place where an animal lives is called its
  habitat.
• An animal lives where it can find food, water,
  shelter and a mate.

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Living things

• All living things (organisms) need food
  (nourishment) to live.
• Living things in an ecosystem depend on each
  other for food.

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• autotroph (from the Greek autos self and trophe
  nutrition) is an organism that produces complex
  organic compounds from simple inorganic molecules
  and an external source of energy, such as light
  or chemical reactions of inorganic compounds.
  Autotrophs are considered producers in a food
  chain.
• Plants and other organisms that carry out
  photosynthesis are phototrophs (or
  photoautotrophs). Bacteria that utilize the
  oxidation of inorganic compounds such as hydrogen
  sulfide, ammonium or ferrous iron as an energy
  source are chemoautotrophs (some are known as
  lithotrophs).

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• A heterotroph (Greek heterone (an)other and
  trophe nutrition) is an organism that requires
  organic substrates to get its carbon for growth
  and development. A heterotroph is known as a
  consumer in the food chain.

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Producers

• Plants are living organisms. They need
  nourishment to survive.
• But
• Plants do not eat other plants or animals.
• Plants are called producers because they are able
  to use light energy from the Sun to produce food
  (sugar) from carbon dioxide and water.

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Consumers

• Consume means eat.
• Animals are consumers because they eat
  (consume) food provided by plants or other
  animals.

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Carnivores

• Some animals, like the kingfisher, eat only other
  animals. These animals are called carnivores.
• Animals that eat OTHER ANIMALS are called
  carnivores.
• carnivores that eat herbivores are called
  secondary consumers
• carnivores that eat other carnivores are called
  tertiary consumerse.g., killer whales in an
  ocean food web ... phytoplankton ? small fishes ?
  seals ? killer whales

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Herbivores

• Some animals do not eat other animals. They
  survive on plants and are known as herbivores.
• Animals that eat ONLY PLANTS are called
  herbivores (or primary consumers).

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Omnivores

• Some animals, like us, eat both plants and
  animals.
• These animals are called omnivores.

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Predator

• A predator eats other animals.

Cats eat fish.
So do bears!
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Predator

• The cat is a predator, because it eats other
  animals.
• The bear is a predator, because it eats other
  animals.
• People are predators too!

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Prey

• Any animal which is hunted and killed by another
  animal for food is prey.

Predator
Prey
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Match the predator to its prey.
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Predators and Prey
Some animals are predators, some are prey - some
are both.
The predator eats the prey, and the prey gets
eaten by the predator.
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Food Chains

• A food chain shows what is eaten.

The fly is eaten by the thrush.
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Food Chains

• A food chain shows what is eaten.

The lettuce is eaten by the rabbit.
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Food chains always start with a plant.
The lettuce is eaten by the slug, the slug is
eaten by the bird.
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Food Chains - a Reminder

• A food chain shows which animals eat other
  animals or plants.
• Plants dont eat things.
• A food chain starts with what gets eaten and the
  arrows point towards what does the eating.
• Food chains only go in one direction.

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Where do the arrows point?
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The top of the food chain.
Some animals are said to be at the top of the
food chain. This is because they are not hunted
by other animals.
No other animal hunts the lion. The lion is at
the top of the food chain. Can you think why?
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primary consumer
producer
secondary consumer
tertiary consumer
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Food Webs

• In the wild, animals may eat more than one thing,
  so they belong to more than one food chain.
• To get the food they need, small herbivores may
  eat lots of different plants, and carnivores may
  eat many different animals.

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Food Webs

• We can show this by using a food web, which is
  just a more complicated version of a food chain.

fox
owl
rabbits
mice
grass
berries
seeds
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• Symbiosis is a close ecological relationship
  between the individuals of two (or more)
  different species.   Sometimes a symbiotic
  relationship benefits both species, sometimes one
  species benefits at the other's expense, and in
  other cases neither species benefits.
• Ecologists use a different term for each type of
  symbiotic relationship
• Mutualism
•   --   both species benefitCommensalism
•   --   one species benefits, the other is
  unaffectedParasitism
•   --   one species benefits, the other is
  harmedCompetition OR predation
•   --   neither species benefitsNeutralism
•   --   both species are unaffected

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Caring for the Environment

• It is in our own best interests to look after the
  world we live in.
• If a habitat is lost or damaged, it has an effect
  on everything else, even if we do not see or
  understand it straight away.
• Remember - once something becomes extinct, its
  gone forever!

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• Because of the large amount of energy that is
  lost at each link, the amount of energy that is
  transferred gets lesser and lesser ...
• The further along the food chain you go, the less
  food (and hence energy) remains available. The
  above energy pyramid shows many trees shrubs
  providing food and energy to giraffes. Note that
  as we go up, there are fewer giraffes than trees
  shrubs and even fewer lions than giraffes ...
  as we go further along a food chain, there are
  fewer and fewer consumers. In other words, a
  large mass of living things at the base is
  required to support a few at the top ... many
  herbivores are needed to support a few carnivores
  

Energy Pyramid
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• 1. If a disease strikes the snake population in
  the food chain shown, what will be the initial
  effect on the populations of hawks and rabbits?
  
• A. The populations of hawks and rabbits will
  decrease.
• B. The populations of hawks and rabbits will
  increase.
• C. The population of hawks will increase. The
  population of rabbits will decrease.
• D. The population of hawks will decrease. The
  population of rabbits will increase.
• 2. In the stable food chain shown below, what
  would you expect to happen initially if you were
  to suddenly double the population of rabbits?
• A. The populations of the other three species
  would also increase.
• B. The populations of the other three species
  would decrease.
• C. The grass population would decrease. The snake
  population and hawk population would increase.
• D. The grass population and hawk population would
  decrease. The snake population would increase.

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• 3. What event within the food chain might lead to
  the graph shown below?
• A. A disease in the population of rabbits.
• B. A disease in the population of snakes.
• C. A disease in the population of hawks.
• D. Its impossible to tell which of the above
  occurred.
• 4. What most likely caused the rabbit population
  to decrease over the first time unit shown in the
  following graph?
• A. A disease in the population of rabbits
• B. A decreasing population of grasses
• C. An increasing population of hawks
• D. A higher-than-ideal population of snakes

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Endangered or Extinct?

• The number of people in the world is growing at
  an alarming rate.
• But this is not true for all animals.
• In some cases, there are only a few of one type
  of animal left in the wild.
• These animals are endangered.
• If they die out completely, they become extinct.

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Why does this happen?

• There are lots of reasons why animals become
  endangered or extinct.
• The most common are
• loss of habitat (woodlands cut down, rivers
  drying up, hedgerows removed).
• chemicals or pollution poison the animals.
• hunting (for sport, their fur, tusks or meat).

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Breaking the Chain

• Organisms living in a habitat depend on each
  other.
• If one part of a food chain dies out or is
  greatly reduced, the consumers have to find
  alternative food, move away, or starve.
• This then affects more consumers in the same way.

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WARM UPS ANSWERS ONLY ON DATED PAPER.

• 1. During a lab experiment, a student used the
  Bunsen burner to heat a flammable mixture in a
  beaker. The student accidentally spilled the
  mixture on the lab table and it caught on fire.
  The students should immediately
• A get the fire extinguisher.
• B tell the instructor.
• C get the fire blanket.
• D put it out with water.
• 2. Only 10 percent of the energy stored in an
  organism can be passed on to the next trophic
  level. Of the remaining energy, some is used for
  the organisms life processes, and the rest is
• A used in reproduction.
• B stored as body tissue.
• C stored as fat.
• D eliminated as thermal energy
• 3. A magazine included advertisements for two
  different garlic supplements to promote healthy
  hearts. The advertisement for Very Good Garlic
  Extract presents evidence that is more valid
  because
• A Information was gathered in a controlled
  manner
• B It lacks a guarantee
• C It lacks personal testimonials to the
  products effectiveness
• D Information was gathered in more than one
  country

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• 1. A student could best demonstrate knowledge of
  how energy flows throughout an ecosystem by
• A. drawing a food web using specific organisms
  living in a pond.
• B. conducting an experiment that demonstrates
  the process of photosynthesis.
• C. labeling a diagram that illustrates
  ecological succession.
• D. making a chart to show the role of bacteria
  in the environment.
• 2. Which group contains terms that are all
  directly associated with one of the organisms
  shown in the diagram below?
• A. herbivore, prey, autotroph, host
• B. predator, scavenger, decomposer, consumer
• C. carnivore, predator, heterotroph,
  multicellular
• D. producer, parasite, fungus, fish

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• 3. Monocystis is an organism that feeds on the
  sperm cells of earthworms. The activities of
  Monocystis eventually cause the infected
  earthwork to become sterile. The relationship
  between the earthworm and the Monocystis is
  classified as
• A. Host parasite
• B. Predator prey
• C. Producer consumer
• D. Scavenger decomposer
• Use the food web below to answer the question
  below.
• 4. Which statement best describes energy in this
  food web?
• A. The energy content of level B depends on the
  energy content of level C.
• B. The energy content of level A depends on
  energy provided from an abiotic source.
• C. The energy content of level C is greater
  than the energy content of level A.
• D. The energy content of level B is transferred
  to level A.

A B C
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• 5. Energy used by producers in a grassland food
  web is provided by
• a. sunlight
• b. photosynthesis
• c. oxygen
• d. carbon dioxide
• 6. After being introduced in the 1930s, the fire
  ant (Solenopsis invicta) became established
  throughout much of the southern United States.
  One biological way to control fire ants might be
  to introduce organisms that are
• a. mutualistic with fire ant queens
• b. nurtured by fire ant workers
• c. preyed on by fire ant drones
• d. parasitic to fire ant larvae

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• 7. Clown fish are small reef fish that seek
  protection from predators by sheltering
  themselves among the stinging tentacles of sea
  anemones. Clown fish are very territorial and can
  potentially scare off predators of sea anemones.
  This relationship is an example of
• a. neutralism
• b. mutualism
• c. parasitism
• d. commensalism
• 8. A student wanted to study the effect of
  temperature on algae levels in a local stream.
  Which items are most useful for gathering data
  and most appropriate for communicating the
  results of her observations?
• A. Research on the internet and videotapes of
  water samples
• B. Microscopes and written descriptions of
  weather patterns.
• C. Ph strips and written observations of stream
  water
• D. Thermometers and graphs of the results
• Sea otters eat mussels, abalone, sea urchins and
  other shellfish. Sea otters were hunted to near
  extinction in the early 1900. What effect did
  this have on the shellfish?
• A. They grew more rapidly.
• B. They reproduced more quickly.
• C. Their population increased.
• D. Their resistance to disease increased.

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• 10. Which of these best describes the
  relationship between epiphytes and trees?
• a. Parasitism
• b. Migration
• c. Commensalism
• d. Predation
• 11. Use the food chain below to answer the
  following question.
• PLANTS gt APHIDS gt SPIDERS gt SPARROWS
• In this food chain, the spiders are
• A. producers
• B. primary consumers
• C. competitors
• D. secondary consumers

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