Download Evolution Review answer key

Name______________________Evolution Review Sheet
1. Define the following terms
Evolution- Species and populations changing
over time.
Common ancestor- Ancestral form two or more
species have descended from.
Convergent evolution- When two species have
evolved similar traits, but are from different
ancestral decent.
Adaptive Radiation- A single ancestral species
gives rise to many new species.
Natural selection- Organisms with better
adaptive traits, survive and pass on their traits.
Adaptation- Traits that make an organism fitter
for its environment.
Speciation- When a new species is formed
Reproductive isolation- inability of a species to
interbreed.
Gene flow- Transfer of genes from one
population to another
Genetic Drift- Change in gene frequency due to
a random event.
Genetic isolation- A population that has little
genetic mixing. (No genes moving in or out of
the population)
Behavioral isolation-When two species don’t
mate because of different courtship behavior.
2. What are homologous structures?
Two structures with the same muscular and bone structure, but different functions
(Divergent evolution)
3. What are analogous structures? Provide an example.
Two structures that have the same function, but different anatomical structures. Ex.
Dolphin and shark fins, butterfly wing and bat wing.
4. How do homologous structures provide evidence of evolution and relationships between
organisms?
They have descended from the common ancestors
based on their bone and muscle structures.
5.What are vestigial structures? Provide an example of a vestigial structure.
A structure that is no longer useful in a specific species, but is still there. Ex. Hips and leg bones
in whales.
6.How can fossils of an extinct organism be found in two different
continents? Pangea was a supercontinent that was separated by
continental drift, and led to similar species being found on two or
more continents.
7. What can you infer about the age of the fossils in the following
diagram?
The fossils on the bottom are the oldest.
8.How do similarities in the stages of embryonic development
in different organisms show common ancestry?
In embryos, the organisms of different species show similar
patterns and strucures in deveolpment .
Species
Sequence of
Amino Acids in
the Same Part of
the Hemoglobin
Molecules
Human
Lys-Glu-His-Iso
Horse
Arg-Lys-His-Lys
Gorilla
Lys-Glu-His-Lys
Chimpanzee
Lys-Glu-His-Iso
Zebra
Arg-Lys-His-Arg
9.How does the relationship of the amino acid
sequence between organisms provide clues to
common ancestry?
The closer the amino acid sequence, the closer
related the two species are.
10.What type of evolution does each model
represent?
Gradualism
Punctuated equilibrium
11.Describe the Endosymbiotic Hypothesis
The mitochondria and chloroplast were engulfed by
early prokaryotic cells to make the first eukaryotic
cells
12.What were the resulting compounds for the
Miller-Urey experiment?
Organic compounds and amino acids were made.
13.Students will be given scenario based questions to
analyze the mechanism of evolution.
If you cut the tails off a population of mice and then
breed them. What type of tails would the offspring
have? Short or regular length tails?
Regular- the cut tail is acquired not inherited.
A specific brand of termite poison claims to kill all
termites in 2 applications. After the first application 85% of the termites were dead. Two months later
the poison was reapplied but only 25% of the remaining population died. What has happened?
The first termites had adaptations that made them more resistant to the poison. They then
reproduced and passes on that adaptation to their offspring.
14. Why are these beaks different? Could all of these birds come from a common ancestor? What is
your
evidence? They’re adapted to different environments and
conditions on different islands. Yes, they have similarities but the
species have become different over time.
15. Give an example of gene flow. How is gene flow different from genetic drift?
Gene flow is genes moving in and out of a population. It is different from genetic drift
because genetic drift is the change in the gene population based on a random event,
like disease or natural disaster.
16. How would the theory of evolution explain the insects that look like leaves or
twigs?
Mimicry- If the organism blended in, it wouldn’t get eaten, and could therefore
reproduce and passed on it’s trait.
17. Given the following graphic, draw a graph that shows each
of the three types of selection (stabilizing, directional and
disruptive)
Stabilizing
Directional
Disruptive
18. How do geographic isolation and reproductive isolation contribute to the development of new species?
When they’re separated or cannot interbreed, they do not exchange genes and the populations change
over time so much that they mechanically cannot interbreed to produce offspring, therefore making the
species two different species.
19. Why did the tortoises on different Galapagos islands become separate
species? Because tthey were sperated geographically and changed over time
because the gene pools were separte.
20. What process explains why two different unrelated organisms
such as the shark and the dolphin can closely resemble each other?
Convergent evolution.
21. New alleles recently appeared in a population of deer; however,
these alleles were not introduced into the existing population
through mutation. Which mechanism is mostly likely responsible for
this?
Gene flow, new deer moved into the population