Natural and Artificial Food: Slide Show

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Natural and Artificial FoodSlide Show
Main topics a natural process
photosynthesis an artificial process
agriculture
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Part One What is Food?All living organisms use
energy.  This includes YOU!  Your body has
stored energy, which you burn up all day.
      But why don't you run out of
energy?Where does more energy come from?
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Your energy comes from FOOD, of course!  But what
is food?Food is other organisms.  Their bodies
also have stored energy, so when you eat them you
take their energy.
This is true whether we eat the organisms whole...
or in processed form.
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OK, but where do those other organisms get their
energy?The animals eat plants, and other
animals. But where do plants get their food?
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Plants make sugars, by combining water, from
the soil carbon dioxide, from the air
light, from the sunThis is photosynthesis,
which means to create ("synthesize") using light
("photo").
The plants created their own food,inside their
bodies.
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All food started with photosynthesis.Even when
we eat other animals, we are eating plant
sugar-- indirectly.You run on solar energy!
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Part Two Natural vs. Artificial Food
For millions of years, people got food by hunting
and gathering.   Hunting means to kill wild
animals. Gathering means to collect wild
plants.
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Hunting and gathering required great work and
knowledge.  Wild animals are hard to catch, and
edible plants are hard to find. So hunting and
gathering could only feed a few people. Earth's
human population was much smaller.
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About 10,000 years ago, various peoples started
breeding plants and animals. People wanted
plants and animals thatgave them more food.  
This was the Agricultural Revolution.  
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People started sowing (planting) plants.  They
kept the biggest and yummiest seeds.The next
year, those seeds grew into plantsthat also had
big, delicious seeds.
By doing this over and over,people in Mexico
turned teosinte grass into corn.
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People also started herding animals-- protecting
and controlling them.  People let big, fat, tame
animals have babies, who would be yummy and tame
like their parents.  This is how people made
tough, skinny boars into fat, friendly pigs.
wild European boar
Domesticated (tame) pig
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These plants and animals were now partly
artificial humans had puposely reshaped them. 
(This is what we call artifice or art.)
The opposite of artificial is natural, but even
artificial things are partly natural.  For
example, people didn't create corn's roots or
leaves or seeds-- but they did make its seeds
bigger.
Natural things are wild they do what they
like.Artificial things are tame they do what we
like.
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Most people kept hunting and gathering, even
after they started herding and planting.But
the change was very important, because herding
and planting people tend to . . .

• guard crops and herds, so they live in one place
• eat more food, so their population grows
• have extra food, so they develop markets
• develop cities, writing, and large governments

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Here's the bottom line The world you know--
its cities, governments, markets, writing, and
manufacturing-- exists because of agriculture. 
Farmers make enough food so that everyone else
can do other things.
Without agriculture, you would be outside right
now, looking for something wild to eat. 
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Photo Credits
EPAUSDANASANPSLOCBLMNOAADOEUSAIDUSDOTCIO
USGSUSFWSU.S. Senate