Chapter 12 Key words

Question 1

Evolution

Answer 1

Descent with modification

Question 2

Gene

Answer 2

DNA sequence that encodes a protein

Question 3

Population

Answer 3

Interbreeding members of the same species occupying the same region

Question 4

Allele

Answer 4

a variant form of a gene

Question 5

Evolution (in term of population)

Answer 5

A genetic change in the population over multiple generations

Question 6

Gene pool

Answer 6

All of the genes and alleles in a population

Question 7

Allele frequencies

Answer 7

Number of copies of 1 allele

Question 8

Macroevolution

Answer 8

Large-scale evolutionary events, such as the appearance of new species

Question 9

Uniformitarianism

Answer 9

Idea that today’s gradual geological processes (erosion and sedimentation) have also occurred in the past, producing changes in the Earth over time

Question 10

Castrophism

Answer 10

Idea that the brief upheavals like floods, earthquakes are responsible for most geological formations

Question 11

Principle of superposition

Answer 11

Idea that lower rock layers are older than those above them

Question 12

Natural Selection

Answer 12

Different reproduction of organisms based on inherited traits

Question 13

Artificial Selection

Answer 13

Selective breeding strategy in which a human allows only organisms with desired traits to reproduce

Question 14

Modern evolutionary synthesis

Answer 14

Idea that genetic mutations create the variations upon which natural selection acts

Question 15

Adaptations

Answer 15

Inherited traits that permits an organism to survive and reproduce

Question 16

Fitness

Answer 16

An organism’s contribution to the next generations’s gene pool

Question 17

Genotype frequencies

Answer 17

of idv. of one genotype / # of idv. in the population

Question 18

Hardy-Wienburg Equation

Answer 18

Highly unlikely situation which allele & genotype frequencies do not change for generations

Question 19

Directional selection

Answer 19

One extreme phenotype is the fittest and the environment selects against the others

Question 20

Disruptive selection

Answer 20

2 extreme phenotypes are fittest

Question 21

Stabilizing selection

Answer 21

Extreme phenotypes are less fit than the optimal intermediate phenotype

Question 22

Balanced polymorphism

Answer 22

Condition in which multiple alleles for the same gene persist indefinitely in a population

Question 23

Heterozygote Advantage

Answer 23

Condition in which a heterozygote has greatest fitness than homozygote, maintaining balanced polymorphism in a population

ex. Sickle cell

Question 24

Sexual Dimorphism

Answer 24

Differences in appearances between the sexes

Question 25

Sexual Selection

Answer 25

a mechanism of evolution that occurs when organisms compete for mates or choose mates based on their preferences

Question 26

Intrasexual selection

Answer 26

Competition between members of the same sex to mate with other sex

Question 27

Intersexual selection

Answer 27

Choices of mates by one sex from among competing members of the opposite sex

Question 28

Genetic drift

Answer 28

A change in the allele frequency in a population due to a random chance ex. group of ants getting stepped on

Question 29

Founder effect

Answer 29

occurs when a subset of the original population separates and creates a new population with fewer alleles

Question 30

Bottleneck effect

Answer 30

when a population is subjected to a disaster, such as habitat loss, disease, or even climate change.

Question 31

Bidirectional Migration

Answer 31

when individuals from two different populations are free to move back and forth.