Name_______________________
Evolution Study Guide
1. Define the following terms:
Spontaneous Generation
The belief that living things came from nonliving things
Biogenesis
All living things come from other living things
Variation
Differences among the same species
Adaptation
A trait that makes an organism successful in
its environment
Coevolution
Two species evolve together, changing and
impacting one another
Natural Selection
The environment selects for desirable traits.
It is the mechanism for “descent of
modification”
Scientifically supported that the universe
began from an explosion in space
Big Bang Theory
2. Explain the experiments and conclusions of the following scientists. Be sure you know how
their experiments disproved spontaneous generation!
Redi: 1668
Conducted experiments to disprove
spontaneous generation
Spallanzani: 1768
Performed more experiments to disprove
spontaneous generation
Pasteur
Disproved spontaneous generation
Control group: jar with meat in it open to the
air
Experimental Group: Jar with meat and covered
so air can pass through but nothing else
Conclusion: maggots don’t come from rotting
meat, rather they are the hatched eggs of flies
Control Group: boiled broth and left the broth
open
Experimental Group: boiled broth and sealed
the flask
Bacteria grew in the open flask and did not
grow in the sealed flask.
Conclusion: bacteria comes from the air
Boiled broth and bent the neck of the flask to
allow air to pass but not any particles.
Conclusion: The open curved neck flask with
the boiled broth did not grow any bacteria.
3. Explain the experiment of the Miller and Urey. Be sure you are familiar with their set- up
apparatus and what their conclusions were.
Miller and Urey recreated the conditions of the primitive earth in a closed experiment. They used
gases believed to have existed on the primitive earth and used an electrical spark to simulate the
energy from lightening. The result was they organic compounds were produced.
4. Who was Oparin? What did he do and conclude?
Oparin is credited with the heterotroph hypothesis. He, along with other scientists, thought
that the early atmosphere contained ammonia, hydrogen gas, water vapor and methane.
According to Oparin, at high temperatures, these gases might have formed simple organic
compounds such as amino acids. When the earth cooled and water vapor condensed these
simple organic compounds collected in the water. Over time these compounds could have
entered complex chemical reactions, fueled by energy from lightning and ultraviolet radiation.
These reactions ultimately would have resulted in the macromolecules essential to life such as
proteins.
5. Explain the endosymbiotic theory.
Early prokaryotic cells may have developed a mutually beneficial relationship early on.
Evidence suggests that a small aerobic prokaryote was engulfed by and began to live and
reproduce inside a larger anaerobic prokaryote. It is thought that these early symbiotic
prokaryotes over time developed into mitochondria capable of aerobic respiration and
chloroplasts capable of photosynthesis.
6. Explain the first organisms on earth (were they prokaryotes or eukaryotes;
anaerobic/aerobic; able to perform photosynthesis).
The first organisms were anaerobic heterotrophic prokaryotes as there was no oxygen in the early
atmosphere. These prokaryotes had to rely on others for a source of food.
7. Explain the different parts of Darwin’s theory of natural selection.
1. Overproduction – more offspring are produced than can survive
2. Competition – only some organisms survive long enough to reproduce
7a. Components of Darwin-Wallaces Theory:
1. Descent with modification – states that evolution is the development of new organisms from
pre-existing organisms over time.
2. Natural Selection – the environment selects the desirable traits
3. Variation – variations within a population are inherited and lead to differences in organisms
4. Adapation- traits that are favorable and improve the organism’s ability to function and
reproduce.
5. Survival of the fittest – states that survivors pass on their variations, resulting in the next
generation will have those variations
6. Fitness – is the measure of an individual’s genetic contribution to the next generation
7. Speciation – over time, small changes accumulate and populations change.
8. Species – a group of organisms that can mate and produce fertile offspring.
8. What was LaMarck’s theory? How did it compare/contrast to Darwins?
1. Use and Disuse – body parts that are used more grow stronger and bigger while body
parts that are not used deteriorate.
2. Inheritance of Acquired Characteristics Theory – physical traits that were changed in an
organism are inherited by their offspring. (these changes are not in the genes!)
9. In the chart below there are evidence to prove evolution. Please define these pieces of
evidence and give examples (if appropriate).
Geologic Evidence (Fossils)
Fossils are remains/traces of organisms that
died long ago. They are often found in rock
layers. Fossil record suggests that different
species were present in the past than today.
Comparative Embryology
This is the study of embryos as they develop.
Similarities of the development of embryos
suggest that the species have a common
ancestor
Comparative Biochemistry
Comparison of amino acids that shows a
relationship between organisms for example
the comparison of cytochrome C between
different organisms.
Organisms with similar internal parts have
different functions in different organisms. This
suggests a common ancestor.
Ex. Bat wing, whale fin, cat leg, human arm
Structures of different organisms have similar
external form and function and different
internal forms and functions. It suggests that
species came from different ancestral lines.
Ex. Bat wing, bird wing, insect wing
These are structures that over time have been
reduced in size and have no function.
This suggests that the structure was once used
by an evolutionary ancestor.
Ex. Human appendix, tailbone
Homologous Structures
Analogous Structures
Vestigial Structures
10. What was the overall conclusion that could be made about all the pieces of evidence that
you listed for question #9?
Overall the evidence demonstrates that different modern organisms once shared a common
ancestor and that over time they have evolved, supporting the theory of evolution.