Final Exam

Question 1

Evolution =

Answer 1

the theory that all life on earth descended from a common ancestor with modifications of genetic material leading to different types of organisms

Question 2

Linnaeus believed -

Answer 2

species did not change over time (immutable)

Question 3

Lamarck believed -

Answer 3

an individual may develop certain traits that it passes on to its offspring

Question 4

Natural selection -

Answer 4

The process through which the most fit individuals pass on their genes to the next generation

Question 5

Darwin and Wallace proposed that -

Answer 5

present day species are the descendants of ancient ancestors that they still resemble in some ways

Question 6

Who proposed natural selection? -

Answer 6

Darwin

Question 7

Evidence of evolution

Answer 7

-Animals are very similar- think about early stages of embryos OR
similar skeletal structure (homologous structures)
- DNA and/or RNA as genetic blueprint
- Geography of similar animals (continental drift)
- Direct observation, like antibiotic-resistant bacteria (within 30 years)
-fossils

Question 8

Fossils

Answer 8

document differences between - past and present organisms

Question 9

Daphne Major island in 1977-

Answer 9

reduced the number of small seeds available to finches, causing many of the small beaked finches to die. This caused an increase in the finches’ average beak size to be between 1976 and 1978

Question 10

Be able to analyze and interpret Evolutionary Trees

Answer 10

The ancestors are located at each branching point in the tree (nodes). Each node represents the most reacent common ancestor of all the branches coming off of it. Nodes that are farther away from the tips of the treee represent older ancestors. Do not count the steps. COMPARE THE MOST RECENT COMMON ANCESTORS

Question 11

Selective Pressures

Answer 11

forces which favor certain traits and decide which organisms pass their genes to the next generation

Question 12

Natural Selection

Answer 12

The process through which the fittest individuals pass on their genes to the next generation

Question 13

Genetic mutation is the source of -

Answer 13

new adaptions and variations within a population.

Question 14

Sexual Selection

Answer 14

Selection of traits with no apparent use besides attracting mates

Question 15

Why is variation allowed?

Answer 15

because most traits are not under any (or under very limited) selective pressure most of the time

Question 16

the source of new adaptations and variation within a population

Answer 16

Genetic mutation

Question 17

Lack of selection

Answer 17

neutral mutations

Question 18

Directional selection

Answer 18

when enviornmental pressures favor one phenotype over the other. (white moth black tree)

Question 19

Stabilizing selection

Answer 19

Elimination of extremes (dark, gray, white mice)

Question 20

Disruptive selection-

Answer 20

Occurs when pressures select against the mean and for the extremes

Question 21

Fittest=

Answer 21

good enough to pass on offspring and pass on traits.

Question 22

More evolved =

Answer 22

better / Evolution has no goal

Question 23

Which scientific concept did Charles Darwin and Alfred Wallace independently discover?

Answer 23

Natural selection

Question 24

Which of the following situations will lead to natural selection?
a. The seeds of two plants land near each other and one grows larger than the other.
b. Two types of fish eat the same kind of food, and one is better able to gather food than the other.
c. Male lions compete for the right to mate with females, with only one possible winner.
d. all of the above

Answer 24

all of the above

Question 25

What is the difference between micro- and macroevolution?

Answer 25

Microevolution describes the evolution of populations, while macroevolution describes the emergence of new species over long periods of time.

Question 26

The wing of a bird and the arm of a human are examples of ________.

Answer 26

homologous structures

Question 27

The fact that DNA sequences are more similar in more closely related organisms is evidence of what?

Answer 27

descent with modification

Question 28

Which situation would most likely lead to allopatric speciation?

Answer 28

a. A flood causes the formation of a new lake.
b. A storm causes several large trees to fall down.
c. A mutation causes a new trait to develop.
d. An injury causes an organism to seek out a new food source.

Question 29

Which variable increases the likelihood of allopatric speciation taking place more quickly?

Answer 29

longer distance between divided groups

Question 30

Describe natural selection and give an example of natural selection at work in a population.

Answer 30

Natural Selection is the process through which individuals pass on their genes to the next generations. The venom of a certain salamander species becoming more poisonous as predation by snakes increases

Question 31

Why do scientists consider vestigial structures evidence for evolution?

Answer 31

Most structures do not exist in an organism without serving some function either presently or in the past.

Question 32

Two species of fish had recently undergone sympatric speciation. The males of each species had a different coloring through which females could identify and choose a partner from their own species. After some time, pollution made the lake so cloudy it was hard for females to distinguish colors. What might take place in this situation?

Answer 32

Two different species may begin to mate with each other and depending on the offspring they might fuse into one species