Download Natural Selection 2006-2007 Study Guide

Evolution & Natural Selection Study Guide KEY
Vocabulary
In your own words, write a definition for each of the following terms in the space provided.
1. adaptation: a characteristic that improves an individual's ability to survive and reproduce in a
particular environment
2. species: a group of organisms that are closely related and can mate to produce fertile offspring
3. evolution: the process in which inherited characteristics within a population change over
generations such that new species sometimes arise
4. fossil: the trace or remains of an organism that lived long ago, most commonly preserved in
sedimentary rock
5. fossil record: the history of life in the geologic past as indicated by the traces or remains of
living things. All the fossils whether they have been discovered or not.
6. vestigial structure: Some structure in an organism that is no longer has an apparent use,
example: appendix in humans.
7. homologous structure: the same organ in different animals under every variety of form and
function
8. variation: The source of differences upon which Natural selection occurs and some individuals
with traits more advantageous than others survive.
9. natural selection: The principle whereas individuals, in a population that have traits or abilities
that give them a competitive advantage over other population members, are more likely to
survive and reproduce.
10. mutation:
11. speciation: The formation of new species as a result of evolution, often a result of geographic
isolation.
12. reproductive success:
____________________________________________________________________
13. generation:
__________________________________________________________________
14. embryo: _____________________________________________________________
15. population: A group of individuals of the same species which live together in the same area at
the same time .
Cell Biology Unit
GJUHSD
1
Study Guide
2006-2007
Fill in the blank:
16. Natural selection occurs because there is variation in a species and some individuals have
traits which are more advantageous than others.
17. When the environment changes a population must adapt or else the population with die out.
18. Structures and behaviors for finding food, protection, and for moving from place to place are
an organism's adaptations to its environment.
19. The process which explains how evolution happens is called Natural Selection.
20. When a population becomes isolated and is no longer able to breed with the original population,
speciation has occurred.
21. The opposable thumb allows humans to grasp objects firmly. Because this feature helped
humans to survive over time, it is called a(n)adaptation.
22. The diversity of living things is the result of Natural Selection.
23. Some structure in organisms no longer have a use, these are called vestigial structures.
24. The primary evidence for common ancestry of all living things is DNA.
25. When a species dies out entirely, it is considered extinct.
26. Adaptations will not be passed down through generations without variation and successful
reproduction as key components of natural selection.
Short Answer – Answer using complete sentences
27. Describe the differences between a community, a population and an ecosystem:
An ecosystem is all the living and non-living components in an area (all the frogs, birds,
and squirrels, and the river, rocks, soil, and sun exposure).
A community is all the living components in an area (all the frogs, birds, and squirrels, etc.).
A population is all the red tailed frogs species living in an area.
28. What are the key components of natural selection?
Overproduction; Genetic variation; Survival Struggle;
Successful Reproduction
29. Describe why climate change, introduction of a new predator and catastrophic events are
environmental factors that could limit the survival of an organism.
All of these are environmental challenges that apply a selective pressure on populations.
Example, if the Earth heats up and weather patterns change this could allow some life
with adaptations to survive and some life without the adaptations will die out.
30. How are natural selection and biodiversity related?
Biodiversity may increase because genetic variation between species increases with
natural selection. Species dying out and being replaced by other species can be a part
of evolution, speciation, and natural selection.
Cell Biology Unit MLK
GJUHSD
2
Study Guide
2006-2007
31. Why can rapidly reproducing organisms, such as insects, develop pesticide resistance?
Rapidly reproducing organisms are able to adapt more quickly because they need short
exposure times to be selected or in other words those that are not adapted to an
environment with pesticides die out leaving only those that are marginally to well
adapted to the pesticide to survive and reproduce. The next generation will only include
those with marginally to well adapted genes.
32. Why don’t individual organisms evolve?
33. Why is camouflage an adaptive strategy for some animals?
Like the stick insects that look like sticks on plants or the leaf insects that look like
leaves, their camouflage allows them to blend into their environment. This is an
adaptation because their predators are not able to find them.
34. Explain why DNA, comparative anatomy and fossils are the three primary lines of evidence for
the theory of evolution.
DNA is the common genetic code of all living organisms, comparative anatomy shows
similar structures which indicated relatedness; and fossil show the sequence of changes
over time
35. Plants have adapted to survive in many different environments. Explain how desert plants have
adapted to survive scarce water supply and extreme heat.
A cactus lives in the desert and stores water in its green stem and has leaves which are
spines. These adaptations are necessary because: 1) the cactus needs to store water
because it does not rain much in the desert; 2) the cactus does not need large leaves
because there is plenty of sun in the desert; 3) the cactus uses it spine leaves to
protect its water supply by limiting transpiration.
Use the following graphs to answer question 36:
36. Referencing each of the graphs about birth weight,
explain why birth weight affects survival rate.
Infant Births by Birth Weight Graph
Most births, approximately 20 percent, involve infants
weighing 7 pounds
Infant Deaths by Birth Weight Graph
The lowest percentage of deaths, approximately 2 percent,
involve infants weighing 7 pounds, which is to say that the
highest survival rate, approximately 98 percent, involve
infants weighing 7 pounds.
These graphs indicate that human babies are best adapted to survive at a birth rate of about 7
pounds, and that babies weighing more or less than 7 pounds are less adapted to survive.
Use the following illustration to answer question 37.
Cell Biology Unit MLK
GJUHSD
3
Study Guide
2006-2007
37. Reptiles are most closely related to birds and mammals based on the structure of the heart.
Explain why using the illustration above.
Use this illustration to answer questions 37 and 38:
http://biodidac.bio.uottawa.ca/
38. The forearms a human, cat, horse and whale are pictured above. Why are they considered
evidence of evolution? These are similar kinds of bones.
39. What function does each structure perform?
Human arm functions to carry and hold things.
Cat leg functions to move by walking and running.
Horse leg functions to move by walking and running.
Whale flipper functions to maneuver while swimming.
Cell Biology Unit MLK
GJUHSD
4
Study Guide
2006-2007