BIOL 117 Exam 2

Islands

________ have diverse animals and plants that are related to, yet different from, their mainland sources.

Speciation

________ occurs after populations become isolated.

Plate tectonics

________ and continental drift effected what organisms were found where as well as habitats.

frequency of genetic variation

5 forces can cause changes to the ________ in a population, thus, enabling a population to evolve.

natural selection

All alleles are replaced equally from generation to generation ________ is not occurring.

Darwin

________ made several observations that helped lead him to believe that species evolve rather than remain fixed.

Morphological

________: Based on analysis of one or more distinct physical diagnostic traits distinguishing one species from another.

gradualistic model

The ________ suggests that it is difficult to indicate when speciation occurred.

Postzygotic

________: Prevent hybrid offspring from developing or breeding.

Mitochondria

________ and chloroplasts are similar in size to bacteria.

Archaea

________: unicellular, cell wall no peptidoglycan.

allele frequencies

As organisms evolve, the ________ are changed on a population level.

genetic composition

Evolution: the change in the ________ of a population over successive generations "Descent with Modification.

Macroevolution

________ occurs at the species level or higher, microevolution occurs at population or lower.

Eukarya

________: mostly multicellular, membrane bound organelles.

Allopatric

________ (allo-="other;- "patric= "homeland) "involves geographic separation of populations from a parent species and subsequent evolution.

Prezygotic

________: prevent mating attempts or make it unlikely that fertilization will be successful.

DNA sequences

Phylogenetic: Compares differences in ________ to identify a single ancestor for two or more different groups Smallest set of interbreeding individuals that share a common ancestor.

extreme phenotypes

Stabilizing selection: Selects against ________.

Sympatric

________ (sym-="same;- "patric= "homeland) "involves speciation occurring within a parent species, remaining in one location, No geographic separation.

Systematics

________: field of study determining evolutionary relationships of organisms /species.

Patterns

________ in the geographical distribution of organisms suggested that organismal lineages change gradually as individuals move into new habitats.

Phylogeny Cladogram

________: visual (graphical) representation of evolutionary relationships.

opposable thumb

A(n) ________, not present in the common ancestor of all mammals, is an ancestral trait of primates.

mechanism of evolution

A(n) ________- differential survival and reproduction of individuals within a population- due to differences in heritable traits- selected traits are most adapted to the environment (that can change !)

Last Universal Common Ancestor

________ (LUCA) is common to all organisms that live, and have lived, on Earth since life began.

prolific reproduction of individuals

A mechanism for the more ________ with favorable traits that survive environmental change because of those traits.

Homologous structures

________- all contain the same sets of organized bones in similar ways.

Gamete Isolation

________- gametes that meet do not fuse to become a zygote.

heritable variation

Organisms exhibit variation that can be passed from one generation to the next- that is, they have ________.

Behavioral Isolation

________- courtship patterns for recognizing mates differ.

Mitochondria

________ were probably once free- living aerobic prokaryotes.

Darwin

________ proposed a mechanism for evolutionary change called Natural Selection.

Natural selection

________ is a process based on the following observations:

Speciation

________: the formation of two species from one original species.

Mitochondria

________ and chloroplasts have their own DNA and make some of their own proteins.

Natural Selection

________= Mechanism for Evolution.

Mitochondria

________ and chloroplasts divide by binary fission.

Evolution

the change in the genetic composition of a population over successive generations "Descent with Modification"

Homologous structures

all contain the same sets of organized bones in similar ways

Stabilizing selection

Selects against extreme phenotypes

Directional selection

Favored phenotype shifts in one direction

Disruptive selection

Selects against average phenotypes

Morphological

Based on analysis of one or more distinct physical diagnostic traits distinguishing one species from another

Phylogenetic

Compares differences in DNA sequences to identify a single ancestor for two or more different groups Smallest set of interbreeding individuals that share a common ancestor

Speciation

the formation of two species from one original species

Sympatric (sym

= "same"; -patric = "homeland") involves speciation occurring within a parent species, remaining in one location, No geographic separation

Allopatric (allo

= "other"; -patric = "homeland") involves geographic separation of populations from a parent species and subsequent evolution

prezygotic

prevent mating attempts or make it unlikely that fertilization will be successful

Habitat Isolation

species occupy different habitats

Temporal Isolation

each reproduces at a different time

Behavioral Isolation

courtship patterns for recognizing mates differ

Mechanical Isolation

incompatible animal genitalia or plant floral structures

Gamete Isolation

gametes that meet do not fuse to become a zygote

postzygotic

Prevent hybrid offspring from developing or breeding

Hybrid Inviability

hybrid zygote is not viable and dies

Hybrid Sterility

hybrid zygote develops into a sterile adult

Stage 1

Organic monomers evolved from inorganic compounds (ex

Stage 2

Organic monomers were joined to form organic polymers (ex

Stage 3

Organic polymers became enclosed in plasma membranes to form protocells (protobionts)

Stage 4

Protobionts acquired the ability to self-replicate

Iron-Sulfur World Hypothesis

It suggests organic molecules reacted with amino acids to form peptides in the presence of iron-nickel sulfides in thermal vents deep at ocean floor

Protein-First Hypothesis

Amino acids can polymerize in the presence of dry heat into proteinoids, Proteins came first, DNA genes came afterwards

RNA-First Hypothesis

It suggests only RNA was needed to progress toward formation of the first cell or cells., RNA can act as both a substrate and an enzyme, Some viruses have only RNA genes, DNA genes would have come after RNA genes via reverse transcription

Example

marsupials able to diversify with less competition, endemic to Americas and Australia

Taxonomy

formal system of classification, naming and grouping species

Systematics

field of study determining evolutionary relationships of organisms / species

Phylogeny/Cladogram

visual (graphical) representation of evolutionary relationships

Bacteria

unicellular, peptidoglycan cell wall

Eukarya

mostly multicellular, membrane bound organelles

Archaea

unicellular, cell wall no peptidoglycan