Loose ends n

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Loose ends n stuff.

• Welcome back to school!
• Bwah Ha Ha Ha

2
Bizarre but True..

• Life came to beor so it was thought.
• Jan Baptista van Helmonts recipe for mice
• Place a dirty shirt or some rags in an open pot
  or barrel containing a few grains of wheat or
  some wheat bran, and in 21 days, mice will
  appear.

3
Bizarre but True..

• Life came to beor so it was thought.
• Recipe for bees
• Kill a young bull, and bury it in an upright
  position so that its horns protrude from the
  ground. After a month, a swarm of bees will fly
  out of the corpse.

4
Starting to make sense...

• The First Real experiment!
• Reallythey think it was
• In 1668, Francesco Redi, an Italian physician,
  did an experiment with flies and wide-mouth jars
  containing meat.

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Starting to make sense...

• The First Real experiment!
• Observation There are flies around meat
  carcasses at the butcher shop.
• Question Where do the flies come from? Does
  rotting meat turn into or produce the flies?
• Hypothesis Rotten meat does not turn into flies.
  Only flies can make more flies.
• Prediction If meat cannot turn into flies,
  rotting meat in a sealed (fly-proof) container
  should not produce flies or maggots.

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Starting to make sense...

• The First Real experiment!
• Testing Wide-mouth jars each containing a piece
  of meat were subjected to several variations of
  openness while all other variables were kept
  the same.control group These jars of meat were
  set out without lids so the meat would be exposed
  to whatever it might be in the butcher
  shop.experimental group(s) One group of jars
  were sealed with lids, and another group of jars
  had gauze placed over them.replication Several
  jars were included in each group.

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Starting to make sense...

• The First Real experiment!
• Data Presence or absence of flies and maggots
  observed in each jar was recorded. In the control
  group of jars, flies were seen entering the jars.
  Later, maggots, then more flies were seen on the
  meat. In the gauze-covered jars, no flies were
  seen in the jars, but were observed around and on
  the gauze, and later a few maggots were seen on
  the meat. In the sealed jars, no maggots or flies
  were ever seen on the meat.

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Starting to make sense...

• The First Real experiment!
• Conclusion(s) Only flies can make more flies. In
  the uncovered jars, flies entered and laid eggs
  on the meat. Maggots hatched from these eggs and
  grew into more adult flies. Adult flies laid eggs
  on the gauze on the gauze-covered jars. These
  eggs or the maggots from them dropped through the
  gauze onto the meat. In the sealed jars, no
  flies, maggots, nor eggs could enter, thus none
  were seen in those jars. Maggots arose only where
  flies were able to lay eggs. This experiment
  disproved the idea of spontaneous generation for
  larger organisms.

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Spontaneous Generation

• Nothing but useless sniveling gibberish concocted
  to quell the onslaught of perplexing questions
  that overload the ignorant mind.
• Spontaneous Generation
• Non-living objects give rise to living organisms.
  
• like worms, beetles, frogs, and salamanders come
  from dust, mud, etc.

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NowThe origins of life.

• What do you think the early earth was like?
• When do you guess life might have started?
• What was it like?
• CD

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In Reality..

• Scientist think life started about 3.6 billion
  years ago.

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Think Back...

• The early earths atmosphere was most likely
  composed of Nitrogen, Water Vapor, Carbon
  Dioxide, and Methane.
• Could you survive?
• Assuming you didnt get toasted by a volcano,
  what very important gas is missing from the above
  mix.
• Are all the rest still out there?
• CD

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In 1953...

• Harlod Urey and Stanley Miller designed an
  experiment where they recreated an early Earth
  environment in a flask with water.
• They then shocked it to simulate lightning.
• Within a week, they had the pre-cursors of
  proteinsthe building blocks of life.

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From 1953 on...

• Scientist now hypothesize that small chemical
  units of life formed gradually over millions of
  years in Earths waters.
• The hypothesis is consistent with evidence
  recorded in fossils.

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http//www.ucmp.berkeley.edu/bacteria/cyanofr.html
The oldest known fossils, in fact, are
cyanobacteria from rocks of western Australia,
dated 3.5 billion years old.
16
Standardize testing questions.

• Use this table to answer the following questions
• Which cell is probably a Animal cell?
• A) cell A B) cell B C) cell C D) None

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Standardize testing questions.

• Use this table to answer the following questions
• Which cell is probably a Plant cell?
• A) cell A B) cell B C) cell C D) None

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Standardize testing questions.

• Use this table to answer the following questions
• Which cell is probably a Prokaryote?
• A) cell A B) cell B C) cell C D) None

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Standardize testing questions.

• Use this table to answer the following questions
• In cell B, where would the genetic material be
  found?
• A) in the mitochondria B) in the vacuoles C)
  in the nucleus D) in the cell membrane

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Standardize testing questions.

• Use this table to answer the following questions
• Which cell(s) most likely contain chloroplast?
• A) cell A B) cell B
• C) cell C D) cells B and C