Chapter 15 : How life Began The Evolution of Microbial Life

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Chapter 15 -How life Began The Evolution of
Microbial Life
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What We Will Learn in Chapter 15
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• We will describe the early atmospheric conditions
  of planet Earth.
• We will look at the evolution of major life forms
  on Earth.
• We will describe Stanley Millers famous 1953
  experiment.
• We will show how biomolecules potentially formed
  from simpler molecules
• We will look at bacteria as an important example
  of prokaryotic life on planet Earth
• We will learn about chemical recycling and
  bioremediation
• A hypothesis concerning the evolution of more
  complex eukaryotic cells will be explored
• 7. We will briefly look at the diversity of
  eukaryotic protists.

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Primitive Earth Conditions
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• The Earth is estimated to be about _______
  billion years old
• Primitive life formed about ______ billion
  years ago
• All early life forms were prokaryotes which
  lack __________.

• Early atmospheric conditions on Earth consisted
  of
• _________ gas (H2)
• _________ gas (CH4)
• _________ (NH3)
• and water. (H2O).
• Notice the lack of ______________.

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Some Major Episodes in the History of Life
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• The timing of speciation events is based on
  fossil evidence and molecular analysis
• 2.2 billion years ago marks the
  __________________ revolution
• ____________ organisms evolved to split water and
  release _________.
• ________ __________ also evolved to use O2 to
  make energy.

I will require you to know the sequence that
various life forms evolved from simple to
complex left to right in the figure above.
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Stanley Millers Organic Synthesis
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Stanley Miller conducted a famous experiment. He
mixed __________ vapor, ________, ________, and
added sparks of _________ to drive a chemical
reaction. _______ __________ formed in the
atmospheric chamber.
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A Four-Stage Hypothesis for the Origin of Life

• Stanley Miller and many others since him have
  shown that _________ ____________ can form
  bio-_____________ such as amino acids, ATP,
  sugars, lipids and even nucleotides.
• Polymerization Monomers such as ____ ______
  could link together by dehydration reactions when
  warm rain falls on _________ or lava or whatever.
  

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A Four-Stage Hypothesis for the Origin of Life

• 3. Origin of Self-Replicating molecules - Some
  RNA molecules can self-replicate others cannot.
  Those that could reproduced the most. Short
  strands of RNA could have produced the first
  __________ from there on came __________.
• 4. Formation of Pre-Cells Chemical reactions
  occur faster if the molecules ______________
  this is the case if you can package the molecules
  within a __________.

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The Origin of Molecular Cooperation
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• Early biomolecules arose from self-replicating
  molecules such as early RNA
• Now to get a plasma __________.
• Circular bubbles form all the time. Lipids form
  spontaneous bubbles called ___________.

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First Life Prokaryotic Bacteria
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Bacteria Single __________ organisms that do
not possess a ___________ they come in various
shapes and styles including 1.________________
_ which are _______________ 2._________________
which are ________________ 3.________________
which are _________________
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Bacteria
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• Bacteria The study of bacteria is called
• _________________________.
• Some bacteria cause disease. _____________ are
  drugs that are developed to kill disease causing
  bacteria.
• Typhoid fever
• Lyme-disease
• Pneumonia
• Bubonic plague
• Malaria
• Meningitis

H. Influenzae bacteria causes pneumonia.
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Some of the Many Beneficial Bacterial Functions
Chemical Recycling
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Chemical Recycling Bacteria are instrumental
in the cycling of elements between the
_____________ and _________ components of
ecosystems.
Figure 19.29 The Nitrogen Cycle
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Some of the Many Beneficial Bacterial Functions
Bioremediation
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_____________ is the use of bacteria to remove
or break down pollutants from water, air or soil.
Examples 1.____________________________ 2.__
__________________________ 3. Wastewater
(sewage) treatment.

Bacteria removing organic waste in a wastewater
treatment facility.
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The Evolution of Eukaryotes
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• From primitive prokaryotes inner membranes
  formed to produce organelles
• ________________ is a term for joining together
  for mutual benefit.
• ___________ and ____________ likely took up
  residence inside of bacteria forming the first
  more complex eukaryotic cells.

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The Evolution of Eukaryotes
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The origin of the eukaryotic cell made more
complex organisms possible.
The next step in the evolution of life were a
strange group of life forms known as the
______________.
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The Diversity of Protists
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Protists Eukaryotic organisms that are not
_________, animals or ____________. Unlike
bacteria, protists do have a ______ that
contains their DNA.
Protozoans
Slime Molds
Seaweeds
Algae
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Thats All for Chapter 15Homework is due ______?