BIO 152 Exam One

Question 1

Gene Flow

Answer 1

Movement of alleles from one population to another

Question 2

Genetic Drift

Answer 2

In small populations, allele frequency may change by chance

Question 3

Nonrandom Mating - Assortative Mating

Answer 3

Phenotypically similar individuals, increases proportion of homozygous individuals

Question 4

Speciation

Answer 4

New species created by existing species that possess their own unique traits

Question 5

Natural Selection

Answer 5

Environmental conditions determine which individuals produce most offspring

Question 6

Artificial Selection

Answer 6

Breeder selects traits

Question 7

Natural selection is a:

Answer 7

Process

Question 8

Result of evolution by natural selection:

Answer 8

Populations adapt to their environment

Question 9

Relative Concept

Answer 9

The most fit phenotype is the one that produces the greatest number of offspring

Question 10

Frequency-Dependent Selection

Answer 10

Fitness of a phenotype depends on its frequency within the population

Question 11

Pleiotropy

Answer 11

One gene affects multiple phenotypic traits that are unrelated

Question 12

Descent with Modification

Answer 12

Given diversity of life

Question 13

Homologous Structures

Answer 13

Structures with different appearances and functions that are derived from the same body part in a common ancestor

Question 14

Convergent Evolution

Answer 14

Similar forms having evolved in different isolated areas because of similar selective pressures in similar environments

Question 15

Natural selection does not imply…

Answer 15

Evolution

Question 16

Sympatric Species

Answer 16

Occur together in an area
-Distinctive entities
-Phenotypically different
-Use different parts of habitat
-Behave different

Question 17

Behavioral Evolution

Answer 17

Sympatric species avoid mating with members of the wrong species in a variety of ways, including:
-Visual Signals
-Sound Production
-Chemical Signals
-Electrical Signals

Question 18

Postzygotic Isolating Mechanisms

Answer 18

Prevent proper function of zygotes after they form

Question 19

Genetic Drift can cause…

Answer 19

Isolation

Question 20

Sympatric Speciation

Answer 20

One species splits into two at a single locality, without the two new species ever having been geographically separated

Question 21

Allopatric Speciation

Answer 21

Geographically separated (allopatric) populations appear much more likely to have evolved substantial differences leading to speciation; gene flow interrupted

Question 22

Genome Doubling/Polyploidy

Answer 22

Individual that has more than two sets of chromosomes = polyploidy

Question 23

Autoploidy

Answer 23

All chromosomes arise from a single species, error in cell division produces tetraploids, cannot produce fertile offspring

Question 24

Allopolyploidy

Answer 24

Two species hybridize, offspring have one copy of the chromosomes of each species
-Infertile unless chromosomes doubled, then can breed with tetraploids

Question 25

At what speeds can Speciation happen?

Answer 25

Speciation can happen rapidly or slowly an can result in changes in a few genes or many genes

Question 26

Ancestral Characteristic

Answer 26

Similarity that is inherited from the most recent common ancestor of an entire group

Question 27

Derived Characteristic

Answer 27

Similarity arose more recently and is shared only by a subset of the species

Question 28

Clade

Answer 28

Species that share a common ancestor as indicated by the possession of shared derived characteristics

Question 29

Synapomorphy

Answer 29

Derived character shared by clade members

Question 30

Plesiomorphies

Answer 30

Ancestral states

Question 31

Symplesiomorphies

Answer 31

Shared ancestral states

Question 32

Homoplasy

Answer 32

A shared character state that has not been inherited from a common ancestor

Question 33

Parsimony

Answer 33

Favors the hypothesis that requires the fewest assumptions

Question 34

Molecular Clocks

Answer 34

Rate of evolution of a molecule is constant through time

Question 34

Monophyletic Group

Answer 34

Includes the most recent common ancestor of the groups and all of its descendants (clade)

Question 35

Paraphyletic Group

Answer 35

Most recent common ancestor of a group but not all its descendants

Question 36

Polyphyletic Group

Answer 36

Does not include most recent common ancestor of all members of the group

Question 37

Homologous Genes

Answer 37

Orthologs - Genes separated by speciation

Question 38

Analogous Genes

Answer 38

Paralogs - Genes separated by duplication

Question 39

Homoplasy/Homoplastic Covergence

Answer 39

Similar traits have evolved independently in different clades

Question 40

Geological Evidence suggests a meteor hit earth...

Answer 40

4.6 billion years ago

Question 41

No rocks existed from the...

Answer 41

Hadean Era (1st 500-700 million years)

Question 42

Life emerged in the...

Answer 42

Archaean Era -Proterozoic (early life) eon occurred -2 billion years into earths history

Question 43

Biomarkers

Answer 43

Look for evidence of ancient organic molecules of biological origin

Question 44

Shifiting plates...

Answer 44

Affect evolution by reproductively isolating populations or allowing previously separate populations to interbreed

Question 45

Cenozoic era began...

Answer 45

65 million years ago

Question 46

Rapid Diversification occurred during the...

Answer 46

Cambrian Explosion (542-488 million years ago)

Question 47

Adaptive Radiations

Answer 47

Rapid period of evolutionary change where many new species arise and adapt to different ecological niches

Question 48

Multicellularity allowed...

Answer 48

Organisms to deal with environment in novel ways through differentiation

Question 49

Hardy-Weinburg Principle/Hardy-Weinburg Equilibrium

Answer 49

-No mutation -No genes are transferred to and from other sources -Random mating is occurring -Population size is large -No selection occurs