Exam 1

Question 1

Define Evolution

Answer 1

Descent with modification (many present day species are descendants of ancestral spcies that were different from current species

Question 2

Aristotle

Answer 2

• Species are fixed, certain “affinities” among orgnaisms
• Life forms can be arranged on a scale of increased complexity
• Each life form, perfect and permanenet, had a place on the ladder

Question 3

Linnaeus

Answer 3

• Binomial Nomenclature
• Nested classification system, grouping similar species in increasingly general categories
• Resemblances not due to evolutionary kinship but pattern for classification

Question 4

Cuvier

Answer 4

Each strata’s boundary reflected catastrophic event

Question 5

Hutton

Answer 5

Gradualism; earth is old and has slowly transformed into its current state

Question 6

Thomas Malthus

Answer 6

• Economist, human population growth is limited by resources

- Optimal conditions -> people have a lot of offspring

Question 7

August Weismann

Answer 7

• Cut a population of lab rat’s tails off and looked at offspring –> they all had tails
• Disproves Lamarck’s Theory

Question 8

Darwin’s Observations

Answer 8

#1 Members of a population often vary in their inherited traits
#2 All species produce more offspring than their environment can support and many of these offspring fail to survive and reproduce

Question 9

Darwin’s Inferences

Answer 9

#1 Individuals whose inherited traits give them a higher probability of surviving and reproducing in a given environment tend to leave more offspring
#2 This unequal ability of individuals to survive and reproduce will lead to the accumulation of favorable traits in the population over generations

Question 10

Lamarck

Answer 10

• Naturalist, proposes organisms change due to environment
• Species drive towards increased complexity
• Traits that are used are inherited
• Use and disuse

Question 11

Define Adapatation

Answer 11

Inherited characteristic of organisms that enhance their survival and reproduction in certain environments

Question 12

Define Natural Selection

Answer 12

A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits

Question 13

Homology

Answer 13

Similarity resulting from common ancestor

-Form and function may be very different

Question 14

Convergent Evolution

Answer 14

The independent evolution of similar features indifferent lineages.

Question 15

Analogous structures

Answer 15

Structures that share similar function, but not common ancestry

Question 16

4 Different Types of Evidence for evolution

Answer 16

1. Direct evidence (eg. MRSA)
2. Convergent
3. The Fossil Record
4. Biogeography

Question 17

Microevolution

Answer 17

A change in allele frequencies in a population over generations

Question 18

Causes of microevolution

Answer 18

1. Natural Selection
2. Genetic Drift
3. Gene Flow

Question 19

Sources of Genetic Variation

Answer 19

1. Formation of New Alleles
2. Altering Gene Number or Position
3. Rapid Reproduction
4. Sexual Reproduction

Question 20

population

Answer 20

Group of individuals of the same species that live in the same area and interbreed, producing fertile offspring

Question 21

Gene pool o

Answer 21

A population is united by its gene pool, the aggregate of all alleles in the population.

Question 22

Conditions for Hardy-Weinberg Equilbrium

Answer 22

1. No mutations
2. Random mating
3. Extremely population size
4. No gene flow

Question 23

Three mechanisms that alter allele frequencies

Answer 23

1. Natural Selection
2. Genetic Drift
3. Gene Flow

Question 24

Natural Selection

Answer 24

Individuals that have certain inherited traits tend to survive and reproduce at higher rates because of those traits

Question 25

Genetic Drift

Answer 25

The change in fluctuations in allele frequencies over generations tend to reduce genetic variation.

Question 26

Genetic Drift includes two mechanisms. What are they?

Answer 26

1. The Founder Effect | 2. The Bottleneck effect

Question 27

The Founder Effect

Answer 27

When a few individuals become isolated from a larger population, this smaller group may establish a new population whose gene pool differs from teh source population

Question 28

The Bottleneck Effect

Answer 28

A severe drop in population size, perhaps due to a sudden change in the environment (fire, flood)

Question 29

The Bottleneck Effect causes certain traits to be _____ or _______

Answer 29

underrepresented or overrepresented