Download Outline Part I

Unit 6 Outline: History of Life:
Name:______________________Date:_________Per:_________
Part I: Population genetics (p. 317-320)
1. What is population genetics?
2. Population genetics is also known as microevolution. What is microevolution?
3. What is a population?
4. The term species can be defined as a group of individual organisms that are capable of interbreeding
(__________________ ____________) to produce fertile offspring in nature
5.
What is a bell curve and how does it show the relationship
between the variations of a trait in an organism?
6. What are the 4 causes of variations of traits?
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7. What is a gene pool?
Part II: Allele Frequency (p.318-319)
1. Allele frequency is the frequency (proportion) of alleles in a population. It can be expressed as a percentage
or a decimal. How is allele frequency calculated?
2. Suppose a population has 10 individuals and there are two alleles (A and a) of a gene. Suppose the individuals
are as follows:
4 AA individuals = 8 A alleles
4 Aa individuals = 4 A alleles and 4 a alleles
2 aa individuals = 4 a alleles
Calculate the frequency of the (A) allele =
Calculate the frequency of the (a) allele =
3. The allele frequencies in a population will remain the same from generation to generation unless acted upon
by outside forces; this is known as the Hardy-Weinberg genetic equilibrium. It describes the “situation”
under which evolution will not occur. This principle is based on a set of five assumptions. What are these
assumptions? (p. 320)
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4. What is an adaptation? Give an example. (p.300)
5. What is acclamation (acquired trait)? Give an example. (Read about Lamark’s ideas of evolution p.298)
Part III: Disruption of Genetic Equilibrium (p. 320-325)
In this section we are going to focus on the external forces that can change the allele frequencies and lead to
EVOLUTION!
Populations
Can Evolve Through
Gene
Mutation
Gene Flow
Non-random Mating
(Sexual selection)
Genetic
Drift
Natural
Selection
1.
What is a mutation and how can mutations result in evolution occurring?
2.
What is the difference between Immigration and Emigration?
3.
How does immigration and emigration affect the numbers of a population and its gene pool? How does this
relate to the gene flow of a population?
4.
What is genetic drift? Why does this occur?
5.
Why is random mating so important to keeping a gene pool stable?
6.
Compare Sexual selection (p.323) to Artificial selection (p.310). Give an example of each.
Part IV: Types of Natural Selection (p. 324-325)
1. What is natural selection?
2. Natural Selection occurs due to variations of traits that give specific organisms an advantage (ex: body size,
body color, etc.). When natural selection is at work over time, the distribution of traits in the population
may change (ex: small, medium and large body size; light, medium and dark body color; etc.). You would see
this as a shift away from the normal bell curve. Scientists observe three general patterns of natural
Normal bell curve →Shifting away from bell curve
selection. Describe each and give an example.
a. Directional Selection
b. Stabilizing Selection
c. Disruptive Selection
3.
Label the distribution curves below as Stabilizing, Directional or
Disruptive Selection.
= original population (before selection)
_______________ Selection
_______________ Selection
= population after selection
_______________ Selection
Part V: Formation of a species & Evolution in Action (p. 326-329)
1. Define speciation.
2.
Classifying organisms according to their internal and external structure and appearance is known as
________________________. Give an example.
3.
What is the biological species concept?
4.
New species can arise from ________________________________ isolation, in which members of a
population are physically separated. Give
5.
Describe reproductive isolation.
Describe the difference between prezygotic and postzygotic isolation. Give examples of each.
6. What is convergent evolution? (p.308-309)
7. What is divergent evolution? (p. 309)
8. What is coevolution? (p.310)
Part VI: Biogenesis (p. 279-281)
1. What is the idea of spontaneous generation, also known as abiogenesis?
2.
Describe Redi’s experiment to disprove the idea of abiogenesis.
3.
Describe Spallanzani’s experiment to disprove the idea of spontaneous generation. What did opponents of
Spallanzani believe that he did wrong in his experiment?
4. Name the scientist and describe the experiment that he
conducted that finally disproved spontaneous generation to
everyone’s satisfaction.
5.
From the experiments of these early Biologists and others who expanded upon their discoveries the Cell
Theory was developed. Which part of the cell theory is based on these experiments? If you need a
refresher the cell theory is stated below.
The Cell Theory:
o All Living Organisms are composed of one or more cells
o Cells are the basic units of structure and function in all organisms.
o All Cells are derived from Pre-Existing Cells.
o In a multicellular organism, the activity of the organism depends upon the total activity of its
independent cells.
Part VII: Earth’s History (p. 282-286)
1. When was our solar system formed?
2.
How old is the Earth? How do we know this?
3.
What is radioactive dating?
4.
What is an isotope?
a. What happens to unstable isotopes?
c. Define the term half-life.
5.
Use carbon-14 and carbon-12 to describe how radioactive dating is done.
6.
Some scientists have suggested that life came from beyond the Earth. This is known as Transpermia. How
do they hypothesize that this occurred?
7.
Describe Oparin’s hypothesis.
8.
Who tested Oparin’s hypothesis?
a. Describe their experiment.
b. What did they learn?
9.
Compare the structure and formation of microspheres and coacervates
10. Why do some scientists believe that early life could possibly be related to these structures?
11. Were the first cells prokaryotes or eukaryotes? Read p. 288-290
a. What are three characteristics of prokaryotes and eukaryotes. (pg 75)
Prokaryotes
Eukaryotes
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12. Define endosymbiosis. Explain how scientists
hypothesize that it occurred.
a.
Endosymbiosis describes the evolution of
(eukaryotic or prokaryotic) cells.
b. A cell that engulfed a photosynthetic
prokaryote eventually evolved into a (plant or animal) cell.
c.
A cell that engulfed a mitochondria like prokaryote eventually evolved into a (plant or animal) cell.
Part VIII: History of Evolutionary Thought (p. 297 – 301)
1. Who was Jean Baptiste de Lamarck and how did he influence the theory of evolution? What was the main
idea behind his theory?
2. What hypothesis did Charles Darwin and Alfred Wallace both propose in the mid-1800’s?
3. What is Darwin’s idea of Descent with Modification?
4. Darwin proposed the theory of Natural Selection as the mechanism (or method) for decent with
modification. Explain his idea of Modification by Natural Selection.
5. What is Genetic Variation? How does it relate to evolution by Natural Selection? (p.318)
6. What is fitness?
Part IX: Patterns and Evidence of Evolution (p. 324-325)
1. List the 4 types of evidence for evolution? (p.302-307)
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2. What is a fossil?
3. Explain how most fossils are formed.
4. What is the law of superposition? Compare fossil X and Z in
the image to the right.
X
5. How is a fossil’s absolute age determined?
6. What is a transitional species? How do transitional species
support the theory of Evolution? Give an example.
Z
7. Scientists often use anatomical similarities and differences to map out the evolution of a species.
Describe the difference between homologous, analogous, and vestigial structures. Give an example of each.
a. Homologous structures
b. Analogous structures
c.
Vestigial structures
8. How can the embryology of an organism help with determining the evolution of a species?
9. How can biological molecules be used to help determine relationships between different species? Give
an example.