Chapter 4: Living Things and their Environment

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Chapter 4 Living Things and their Environment
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Aim What is the difference between abiotic and
biotic factors?
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Ecosystems

• All the living and nonliving things in an area
• Ecology-the study how all these things interact
  in order to survive
• There are many different types of ecosystems
• All have the same parts
• Abiotic factors
• Biotic factors

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• Abiotic Factors

• Biotic Factors

• Living parts of an ecosystem
• Plants, animals, fungi, protists and bacteria

• Nonliving parts of an ecosystem
• Living things need these nonliving things to
  survive
• Water, minerals, sunlight, air, climate and soil

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Aim What is a Prairie ecosystem like?
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Blackland Prairie

• Located in Texas
• Largest remaining prairie in America
• Was once covered in wild grasses
• Rich black soil was found here
• Land was occupied by buffalo
• snakes, lizards, types of birds, raccoons,
  coyotes, deer and bats
• 50 different kinds of tall and short grasses
• Many types of flowers

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• Now the prairie is used for planting crops
  (wheat, corn) and cattle grazing
• When towns, cities and farms were built the
  buffalo and many other animals left, such as
  black bears and jaguars
• Some animals came, such as armadillos

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Aim How are living things organized?
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Population

• All the organisms of a species living in the same
  area
• Populations of the Blackland prairie
• Armadillos
• Badgers
• Indian grass
• Pond algae
• Soil bacteria
• Scientists want to know how these populations
  interact with one another

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Communities

• All the populations living in an area
• Scientists study the interactions of different
  populations in an ecosystems community
• This helps them to understand what makes an
  ecosystem grow

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Aim What is the difference between niches and
habitats?
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Habitat

• The place where an organism lives
• Examples
• red bats habitat is above ground
• Chorus frog-ponds of Blacklands
• Bees-beehive
• Sharks-live in the ocean

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Niches

• Role of an organism in the community
• No 2 species can have the same niche
• They would have to be identical for this to occur
• No 2 species are identical
• Scientists study niches and habitats to find out
  if a community is healthy or in trouble
• Includes
• What a species eats
• What eats the species
• Active by day or night
• Kind of environment the species needs to live in

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Aim What happens when habitats change?
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• Habitats can change year to year
• This affects the organisms
• Animals either finds a new habitat or adapt to
  the changes in their environment
• Ex spadefoot toad is able to survive during a
  drought
• The toad digs with its hind feet to cover itself
  with soil
• Absorbs water from the soil which contains clay

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Aim What is the treasure of the Blackland
Prairie?
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• Treasure is the soil
• Topsoil-dark brown to black
• Rich in humus-partly decayed plant matter
  produced by bacteria and fungi
• Full of minerals
• Magnesium-helps produce chlorophyll
• Calcium-important element of cell walls
• Good to grow crops

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Aim What does a food chain represent?
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Food Chains

• Energy in an ecosystem comes from the sun
• The energy in food is passed from one organism to
  another
• Represents the movement of energy from one
  organism to another
• 1st organism is a plant (producers)
• Suns energy is stored in foods the plant makes

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• 2nd organism is consumer (herbivore)
• 3rd organism is consumer (carnivore)
• All organisms receive the suns energy
• Food chains end with decomposers-eat dead animals
  and plants

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Aim What is a food web?
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Food Webs

• Shows the relationship between all of the species
  in a community
• Shows how populations must compete for food
• Map of overlapping food chains
• Begin with producers
• use Suns energy to make their own food
• Ex grasses, trees, algae (oceans)

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• Consumers-cant make their own food
• Get energy from other organisms
• Grouped according to what they eat
• Herbivores-eat only plants (producers)
• Ex grasshoppers, rabbits, mice
• Carnivores-eat only other animals
• Ex wolves, foxes, sharks
• Omnivore-eats both plants and animals
• Ex humans, bears

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• Decomposers
• Every food web ends with decomposers
• Breakdown dead matter into substances that can be
  used by producers
• Some of the substances return to the soil
• Ex insects, bacteria, fungi

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Aim How are populations connected?
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• Populations in an ecosystem are connected
  together
• If one animal population changes, it will affect
  the animal population that eats that animal
• A change in a population affects all the
  organisms in the food web
• Organisms may adapt to the changes, especially
  when they eat more than one animal
• Animals compete for food
• Sometimes competition causes an animal to change
  its habitat

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Aim How does energy move in a community?
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Energy Pyramid

• Producers get energy from the sun
• Consumers get energy from the foods they eat
• Energy is lost as it passes from one organism to
  another
• This is shown in the energy pyramid
• Shows there is less food at the top of the
  pyramid than at the base
• Organisms decrease as you move up the pyramid

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• energy decreases as you move up the pyramid
• 90 of energy is lost from one level to the next

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Aim What is the water cycle?
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Aim What is the carbon cycle?
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Aim What is the nitrogen cycle?
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Aim Why is it important to recycle?
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• Dead matter is important to living things
• Decomposers turn dead matter into substances
  other organisms need to survive
• Break down dead plant parts into carbon dioxide
  and ammonia-contains nitrogen
• All organisms need nitrogen in order to make
  proteins
• Nitrogen found in plant fertilzers

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Composting

• Is a way to recycle plant material
• Compost is used to make soil more fertile
• To make compost take 3 parts leaves and plant
  material, 1 part fresh grass and one part food
  scraps
• Earthworms can be used to turn the leaves, grass
  and food scraps into compost

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Importance of Recycling

• Nonrenewable resources will eventually be used
  up, such as oil and natural gas
• Renewable resources, such as wood, can be
  replenished
• By cutting down trees we are destroying animals
  homes
• If we recycle paper and paper products we will be
  decreasing the destruction of forests