Title: Chapter 15 : How life Began The Evolution of Microbial Life
1Chapter 15 -How life Began The Evolution of
Microbial Life
1
2What 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.
3 Primitive Earth Conditions
3
- 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 ______________.
4Some Major Episodes in the History of Life
4
- 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.
5Stanley Millers Organic Synthesis
5
Stanley Miller conducted a famous experiment. He
mixed __________ vapor, ________, ________, and
added sparks of _________ to drive a chemical
reaction. _______ __________ formed in the
atmospheric chamber.
6A 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.
6
7A 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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8The 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 ___________.
9First 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 _________________
10Bacteria
10
- 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.
11Some of the Many Beneficial Bacterial Functions
Chemical Recycling
11
Chemical Recycling Bacteria are instrumental
in the cycling of elements between the
_____________ and _________ components of
ecosystems.
Figure 19.29 The Nitrogen Cycle
12Some of the Many Beneficial Bacterial Functions
Bioremediation
12
_____________ 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.
13The 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.
14The 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
______________.
15The 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
16Thats All for Chapter 15Homework is due ______?