Download Name: Date: Block: ______ Evolution Review Worksheet Early

Name: ___________________________ Date: ___________________________ Block: _________
Evolution Review Worksheet
Early Ideas about Evolution and Darwin’s Observations
Matching: On the line provided write the letter of the answer that best matches the
description
a. Lyell and Hutton
b. Lamarck
c. Malthus
__A__ 1. Studied the geological changes that shape the Earth.
__B__ 2. Stated that the inheritance of acquired traits caused change in species overtime.
__C__ 3. Recognized that food and living space were limited factors for population growth.
__B_ 4. Proposed that acquired traits could be passed on to an organism’s offspring.
__B_ 5. Proposed that selective use or disuse of organs, organisms acquired or lost certain
traits in their lifetime.
__A_ 6. Recognized that processes that shaped the Earth in the past are the same processes
that operate in the present
__A 7. Recognized that the Earth is many millions of years old.
Evidence of Evolution
Define the following terms:
1. Evolution: A long slow change in organisms over long periods of time. A change
in the relative frequencies of alleles in the gene pool of a population
2. Divergent Evolution: Species give rise to many species that may appear different
externally, but are internally similar
3. Convergent Evolution: The process whereby organism not closely related
independently evolve similar traits as a result of having adapted to similar
environmental niche (similar selective pressures)
4. What are homologous structures? Provide an example. Structures that come from
the same origin. Ex – the forelimbs of humans, cats, whales and bats forelimbs.
5. What are analogous structures? Provide an example. Look similar on the outside,
same function, but not the same origin. Examples – Fins of Dolphins and fish
6. What are vestigial structures? Provide an example. An organ or structure that
serves no useful function in an organism. Example – appendix, hind legs or whales.
7. Distinguish between Relative Dating and Radioactive Dating.
Relative Dating is a technique that is used by scientists to determine the age of fossils
relative to other fossils in different layers. Relative dating provide the approximate
age of fossils. Radioactive dating is a technique used by scientist to determine the
actual age of fossils on the basis of the amounts of radioactive isotopes it contains.
8. Explain why the formation of fossils is a chancy process.
The fossil record is not complete for many animals die and vanish without leaving a
trace. Soft bodied animals tend decay and without leaving a trace.
9. In what Era did the following organisms (Fish, Reptiles, Flowering Plants,
Mammals, and Dinosaurs) first appear? See text book – geological time scale
Types of Selection
1. What is Artificial Selection? Use an example to explain your answer. Artificial
selection is a technique in which the intervention of humans only allows selected
organisms to produce offspring.
2. What is the process called that in nature works in a similar manner to artificial
selection? Natural Selection
3. When birds compete for food and space in which to build nests and raise
young, what determines who among the contenders will win the struggle for
existence? Individuals that possess characteristics best suited to their
environment. (Those that are best adapted)
4a. Explain the process of natural selection by discussing the Peppered Moth
Experiment.
The peppered moth before the industrial revolution was mostly white as a
population and oak barks were also white. After the industrial revolution the tree
barks darkened and the population of peppered moths turned dark. The
hypothesis is: If moths have two possible colours then the colour that is the same
as the tree bark will have a better survival rate
b. How did Kettlewell test his hypothesis?
Kettlewell raised both dark and light moths. Then he marked and released these
moths in two types of forests, one with dark oak trees and one with light oak trees.
Then he re-captured the moths and counted them. He found that more dark moths
survived in dark oak forests and more light moths survived in light oak forests.
5. Draw a graph after the following types of selection have occurred:
Disruptive, Stabilizing, and Directional. Under each graph state whether
the intermediate, an extreme, or both extremes are being selected for.
See notes
Disruptive – Two extremes are favored
Stabalizing – Intermediate is favored
Directional – One extreme is favored
Genetics:
1. What causes some of the variation in nature?
Genes, carriers of inheritable characteristics are sources of random variation.
2. What is a population? Provide an example.
A collection of individuals of a given species in a given area whose members
can breed with other another. Ex - Population of squirrels in Crescent park.
3. What is a gene pool? A common group of genes shared by members of a
population.
4. What is an allele? One of the number of different forms of the same gene for
a specific trait.
5. What is relative frequency? The number of times an allele occurs in a gene
pool compared with the number of times other alleles for the same gene occurs
is called the relative frequency of the allele.
6. What is genetic drift? Explain the difference between the terms
“Bottleneck” and Founder Effect. Genetic drift is the random change in the
frequency of alleles by chance. It reduces the genetic variation in a
population.
Bottleneck – Natural disasters occur which reduces the number in a
population to the point that they are almost extinct. The alleles become over
or misrepresented.
Founder Effect occurs when a small population colonizes a new area. Again
genes/alleles are over or misrepresented.
7. Define gene flow. How does gene flow relate to speciation?
Gene flow refers to the movement of gene into or out of a population causing
changes in the population’s gene pool. (caused by migration and emigration
of populations. Gene flow between two populations reduces the likelihood of
speciation.
8. What are the three components of a nucleotide?
Nitrogenous base
Sugar
Phosphate group
9. Name the four types of nitrogenous bases and explain how they pair.
Adenine and Thymine Pair
Guanine and Cytosine Pair
10. What is a mutation? What can cause a mutation? A mutation is a change
in the DNA sequence/genetic code. A mutation can be caused by mutagens,
such as chemicals, UV radiation, sunlight etc.
11. Explain what a frame shift mutation is.
A frame shift mutation is a mutation caused by the insertion or deletion
of a nitrogenous base. Due to the triplet nature of gene expression by
codons, an insertion or deletion can cause the reading frame to shift. The
translation of codons may results in the production of different proteins.
Speciation:
1. Define the word species. What is one problem with the definition?
A species is a group of similar looking organisms that breed with one another
and produce fertile offspring in their natural environment. One problem with
this definition is that it is not applicable to asexual reproducing organisms.
Another issue is that different species are capable of breeding with one another.
2. Explain what Geographical Isolation is.
Geographical isolation involves the separation of populations by physical
barriers, such as mountain ranges, bodies or water and man made barriers.
3. What is reproductive isolation? What is the difference between a Postzygotic
Barrier and a Prezygotic Barrier? Provide an example of each. Reproductive
isolation is when organisms in a population can no longer mate, or produce
fertile offspring, even following the removal of a geographic barrier.
A prezygotic barrier prevents fertilization from occurring. A post zygotic barrier
occurs after fertilization and it prevents the zygote from developing properly.
Prezygotic example – Gametic isolation, temporal, behavioral, habitat isolation,
mechanical isolation
Postzygtic – hybrid sterility, hybrid breakdown and hybrid in viability
4. Identify Process. On the lines provided use the numbers 1-6 to indicate the
order in which the following events occurred in the speciation of the
Galapagos Finches.
__3__
__6__
__1__
___4_
__2__
__5__
changes in the gene pool
continued evolution
Founders arrive
Reproductive isolation
Separation of population
Ecological competition