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Bio Review Chapters 13-15
Bio 101 Chapters 13-15
47
Biology
Undergraduate 1
11/24/2010

Additional Biology Flashcards

 


 

Cards

Term
Evolution
Definition
Genetic change in population overtime
Term
Convergent Evolution
Definition
Organism similar characteristic b/c evolves in similar environmental conditions but not closely related
Term
Microevolution
Definition
Relatively short term changes in allele frequencies within a population or species
Term
5 Mechanisms of microevolution
Definition

Natural selection

Mutation

Nonrandom mating

Gene Flow

Genetic Drift

Term
Natural Selection
Definition

Results from differential reporductive success' success with individuals with particular phenotype, individuals vary, more individuals than resources can support, struggle for existence, individuals with best adaptions pass advantages to offspring, adaptions become more common

 

Term
Mutations
Definition
Raw material for evolution
Term
Nonrandom Mating
Definition
Many factors influence mate choice
Term
Genetic Drift
Definition
Change due to chance
Term
Gene Flow
Definition
Migration brings in or takes away alleles (individuals/gametes disperse)
Term
2 types of Genetic Drift and thier definitions
Definition

Founder effect- small group of individuals form new population.

 

Bottleneck effect - members of population die leaving on a few survivors

Term
Sexual Selection
Definition
Variation in ability to attract mate (blue jay)
Term
Artificial Selection
Definition
Breed only those best expressing those traits
Term
Gene Pool
Definition
Entire collection of genes and their alleles in a population
Term
Concept of fitness
Definition
By itself survival is not enough but fitness depens on surviving to reproduce fertile offspring that live long enough to reproduce.
Term
3 modes of Natural Selection
Definition

Directional Selection

Disruptive Selection

Stabilizing Selection

Term
Directonal Selection
Definition
One extreme phenotype id fittest, others selected against
Term
Disruptive Selection
Definition
2 or more extreme phenoptypes are fitter than intermediate phenotype
Term
Stabilizing Selection
Definition

Most Common

Extreme phenotypes are less than the optimal intermediate phenotype

Term
Polymorphism
Definition
Multiple alleles of a gene persist indefinitely in the population
Term
Macroevolution
Definition
Large complex changes
Term
Difference between macroevolution and microevolution
Definition

Macroevolution-large complex changes

Microevolution-short term changes in allele frequencies within a population or species, occurs much smaler scale

Term

Carlolus Linneaus

2 main names used to classify organism

Definition

Designed hierarchical system of classification.

Genus and species

ex. Homo sapiens

Term
Species
Definition
Population or group of populations whose members can interbreed and produce fertile offspring
Term
How new species arise
Definition
Speciation occurs when members of a population can no longer interbreed
Term
3 methods of speciation
Definition

Allopatric speciation - geologic event or structure physically seperates population in 2 groups.

Parapatric speciation - part of a population enters a new habitat bordering the range of the parent species.

Sympatric seciation - population diverge genetically while living in the same physical area.

Term
Reproductive Barriers
Definition

Prezygotic Barriers -  prevent fertilization.

ecological or habitat isolation, temporal Isolation - (timing differences),behavioral isolation (intricate mating dances), mechanical isolation (reproductive anatomy), gametic isolation (external fertilization)

 

Postzygotic Barriers - prevent viable or fertile offspring.

 

Hybrid inviablity (embryo dies early), hybrid infertility (mules are infertile)

Term
Pace of Evolution
Definition

Graduated - evolution proceeds in small, incremental changes over many generations.

 

Punctuated Equilibrium - long periods of statis alternates with relatively brief bursts of fast evolutionary change between them.

Term
Adaptive Radiation
Definition
Population faced with a diverse environment gives rise to multiple specialized forms in a relatively short time
Term
3 reasons Adaptive radiation occurs
Definition

Individuals colonizing new isolated habitat

Some members of a population inherit a selective advantage (new trait)

Survive major environmental change

Term
Extinction
Definition
death of all members of a species
Term
Reason Extinction occurs
Definition

Failure to adapt to environmental change

Habitate loss

New predators

New diseases

Bad luck

How fast the environment is changing relative to the rate the population evolves

Term
2 main theories for mass extinctions
Definition

Impact theory - meteorite/comet crash sends debris blocking sunlight.

 

Plate tectonics - dramatic enviromental from moving of Earth's crust profoundly affected life

Term
Tree diagram
Definition

Evolutionary tree or Phylogenies

depicts a species relationships based on descent from common ancestors

Term
What does a tree diagram show
Definition

Branching indicates divergence

Discontinuation is extinction

Angle of branch point indicates gradualism or punctuated equilibrium

Orginally derived from fossil data

Newer molecular data based on mitochondrial DNA

Term

Paleontology

 

Definition
study of fossil remains or other clues to past life
Term
Fossil
Definition
any efidence of an organism form more than 10,000 years ago
Term
Name of current era, period and epoch
Definition

Era - Cenozoic

Period - Quatinary

epoch - Recent

Term
Radiometric Dating
Definition
Type of absolute dating that uses radioactive isotopes as a clock
Term
Most commonly used isotope
Definition
Carbon 14
Term
Biogeography
Definition

 

Study of distribution pattern of species across the planet

Term

Homologous Structures

 

Definition
Similarity between 2 structures reflect common ancestry
Term
Analogous
Definition
Similiar adaptations in organisms that do not share the same evolutionary history and this is due to convergent evolution (think birds wings and insect wings)
Term
Vestigial Structure
Definition
No apparent function in one species but homologous to a functional organ in another (ex. in humans - muscle above ear,tailbone)
Term
Molecular Evidence
Definition
All species use the same genetic code
Term
Who is our closest monkey relative
Definition
Chimp
Term
Systematics & 2 banches
Definition
Describing and naming a species by taxonomy & ecplaining evolutionary relationships by phylogenetics
Term
Cladogram
Definition
a phylogenetic system that defines groups by shared derived characters
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