Biology 106 Exam #2

Front 1

Evolution

Back 1

Genetic changes in populations over time. Goal is to increase fitness

Front 2

Natural Selection Conditons

Back 2

1. Variation

2. Over Production

3. Limits on Pop Growth

4. Differential reproduction success

Front 3

Microevolution

Back 3

changed in allele or genotype frequencies that occur over a few generations.

Front 4

Macroevolution

Back 4

Results in a new species over more generations

Front 5

Population Genetics

Back 5

The study of genetic variability within a population and the forces that act on it

Front 6

Loci

Back 6

Same gene different but different allele

Front 7

Hardy Weinberg Principle

Back 7

With the absence of outside forces allele and genotype frequencies do not change from generation to generation.

*p+q=1

*p^2+2pq+q^2=1

Rare in nature but used as an experimental controll

Front 8

Hardy Weinberg conditions for genetic equilibrium

Back 8

1. Population size is large

2. Random mating

3. No mutation

4. No migration

5. No selection

Front 9

5 agents for evolution

Back 9

1. Genetic Drift- changes in an allele frequency due to random chance. Affects small pops

2. Inbreeding- mating with relatives increases homozygosity.

3. Mutation-Changes in DNA

4. Gene Flow-Movement of alleles/genetic info between populations. Works against GD and NS

5. Natural Selection- Individuals with high fitness survive.

Front 10

Bottle Neck Affect

Back 10

Loss of genetic variability due to the lack of movement and reduced population size. Usually happens because of an event that drastically reduces the size of the population.

Front 11

Founder Affect

Back 11

Loss of genetic variablity due one or few individuals dispersing and starting their own population.

Front 12

Assortive Inbreeding

Back 12

Similar phenotypes breeding, increase in homozygous frequencies

Front 13

Disassortive Inbreeding

Back 13

dissimilar phenotypes breeding, increase in heterozygous frequencies

Front 14

3 Types of Selection

Back 14

1. Stabilizing-acts to eliminate both extreme phenotypes

2. Directional- acts to eliminate one extreme phenotype

3. Disruptive- acts to eliminates intermediate phenotype

Front 15

Evidence for Evolution

Back 15

1. Fossil Records

2. Biogeography-study of the geographical distributions of extinct and extant species

3. Homoplasy- similar features not inherited from a common recent ancestor.

4. Selective breeding/artificial selection:

5. Homologes- similaritys due to decent from a common ancestor

6. Experimental evidence of adaptation

Front 16

Taxonomy

Back 16

Naming and describing organisms

Front 17

Binomial Nomenclature

Back 17

Current Naming System, all species assigned a unique 2 part name.

First Part: Generic name, genus

Second Part: Specific epithet

Front 18

Phylogeny

Back 18

The evolutionary history of species or a group of species

Front 19

Phylogenic Tree

Back 19

tress that reflect relatedness and also reflect time and genetic distance

Branches are proportional to time or genetic similarity or distance

Front 20

Cladogram

Back 20

demonstrate groups with shared characteristics and relatedness

Front 21

Systematics

Back 21

The study of organisms evolutionary relationships and construction of phylogenetic

Front 22

Divergent evolution

Back 22

2 species share a common ancestor but evolved differently

Front 23

Convergent Evolution

Back 23

2 species share characteristics but have different ancestors.

Front 24

Derived Characteristics

Back 24

Shared trait in species that is varied (hair)

Front 25

Ancestral Characteristics

Back 25

Similarity passed down (Nose Shape)

Front 26

Monophyletic Taxon

Back 26

All decedents of the most recent common ancestor

Front 27

Paraphyletic Taxon

Back 27

Share a common ancestor but not all decedents

Front 28

Polyphyletic Group

Back 28

Does not share the most recent common ancestor.

Front 29

Adaptation

Back 29

A change in structure, physiology or behavior that increases an organisms fitness in a given environment.

Front 30

Adaptive Radiation

Back 30

A process in which organisms diversify rapidly from an ancestral species into many new forms. Particularly when a change in the environment makes new resources available. Creates new selective pressures or opens up environmental niches

Front 31

Morphological Species Concept

Back 31

Grouped/classified organisms based on structural similarities and differences; especially reproductive structures

Front 32

Genealogical Species Concept (aka the phylogenetic species concept)

Back 32

A population mist have undergone evoultion long enough for significant differences in diagnostic traits to emerge; a single lineage

Front 33

Species

Back 33

A group of individuals that maintains a distinct set of attributes in nature for a specific space and time. Usually driven by reproductive isolation

Front 34

Sympatric Speciation

Back 34

from the same homelands

Front 35

Allopatric speciation

Back 35

from different homelands, populations are geographically separated

Front 36

Reproductive Isolating Mechanism

Back 36

Barriers that prevent a species or population from interbreeding with another species or population. Each gene pool is isolated from the others

Front 37

Pre zygotic Isolating Mechanisms

Back 37

Isolation occurs before fertilization. Prevents fertilization. Some reasons are separation in time, different mating behaviors, separation in location, incomplete genital structures, or egg and sperm are not compatable.

Front 38

Post zygotic Isolating Mechanisms

Back 38

Fertilization sometimes occurs but there is a reproduction failure. The offspring is not viable. Can be a spontaneous abortion, infertile offspring, or infertile f2 generation and so on.

Front 39

Speciation

Back 39

The evolution of a new species