Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

111 Cards in this Set

  • Front
  • Back
Describe genotype Vs. pheotype of an individual organism
Genotype is the genetic makeup, and phenotype is the measurable, physical traits. The genontype determines the phenotype.
definition of allele
variant form of a gene
definition gene pool
total # of genes in a population at any one time
definition of "gene flow"
genetic exchange due to migration of fertile individuals or gametes b/n populations
p+q=1....what do p and q stand for?
Different gene alleles.
having a pair of identical alleles for a gene locus
having two different alles at a gene locus
having two different alles at a gene locus
fully expressed in the phenotype
not expressed in the phenotype
different alleles both affect the phenotype in different ways
A geneticist would consider evolution as
a change in the gentic composition of a population's allele frequency over time
gene pool
all the alleles that exist in a population for a particular gene or sets of genes
Hardy Weinberg Principle
Alle frequencies remain constant in succeeding generations as long as no evolutionary change occurs
Hardy Weinberg Equilibrium
allele frequencies do not change between generations.
Hardy Weinberg Assumptions
1)There is no selection
2)There is no mutation
3)There is no migration
4)Population is large
5)Mating is random
Mendel's Law of segregation
hereditary units are passed on unaltered between generations
site on a chromosome
Two types of Variability
Discrete and continuous
Discrete variation
2 or several distinct types
Continuous variation
many intermediate phenotypes between extremes
Sources of variability
Genetic Recombination
Genetic Recombination
formation in the offspring of gene combinations not found in either parents
A change in the base sequence of DNA
Key point of Mutation
New alleles originate only by mutation
Nucleotide bases
Adenine A
Guanine G
Thymine T
Cytosine C
Nucleotide bases
Adenine A
Guanine G
Thymine T
Cytosine C
set of 3 nucleotide bases, coding for a particular amino acid (via tRNA)
Point Mutations
Substitution of single base pair
Transition Mutation
A switch between the purines
purine-->purine (A-->G)
Transversion Mutation
less common, type of mutation, switch between purine and pynmidine
True or False:
Mutation in directed by the environment
False. environmental factors can indude mutations but these are not necessarily adaptive
Influences on mutation rates
chemical mutagens
poor nutrition
any trace left by an organism that lived in the past
the study of fossils
Fossil Categories
Compression and impression
Casts and Molds
Unaltered remains (rare)
Types of Bias in fossil record
Examples of Geographic fossil record
Aquatic habitats favored
Lowland plains
most animal phyla lack hard parts, bone or shell
phyla inhibiting marine or swamp environments favored
old sedimentary rocks are rare
metamorphosis of rocks destroys fossils
Compression and impression fossils
burial prior to decomposition
Permineralized fossils
minerals precipitate into cells
Casts and molds
remains decay/dissolve away
new material fills space
space left unfilled
Unaltered remains (rare)
decomposition is incomplete
Anaerobic conditions
Two types of reconstructive dating techniques
Relative dating
Absolute dating
Relative dating
strata nearer the surface are younger than deeper strata
Absolute dating
some elements exist naturally

isotopes are incorporated into organisms in this "background ratio

Unstable isotopes decay at a fixed rate.
Three parts of Geologic Time scale
meaning of phanerozoic
physical life
types of animals in Paleozoic level
Aquatic animals are in ________ level
types of animals in the mesozoic level
types of animals in the cenozoic level
Birds and mammals are in the ________level
What causes transitions in fossil record?
diversification of certain taxonomic groups
what factors allow for transitions in fossil records?
Environmental change
gene flow
movement of alleles between populations
genetic drift
random changes in allele frequency from one generation to the next
science of identifying and naming taxa
father of taxonomy
carl linnaeus
physical structure of an organism
group animals into species
split species apart
Morphological species concept
species based on morphology
similar organisms likely to be related
"type specimen" = ideal of species
Convergent evolution
similarity between unrelated species that result from independent evolutionary change in response to similar environmental conditions
Placental mammals
baby born when developed
Australian marsupials
baby develops in the pouch
Biological Species concept
species are potentially interbreeding natural populations that are reproductively isolated from other such groups.
Why evolutionary force is prevented between species
Gene flow
barriers to gene flow
Prezygotic barriers
Postzygotic barriers
definition: Prezygotic barriers
reduce likelyhood of hybrid zygotes
definition: postzygotic barriers
reduce fitness of hybrid zygotes
Examples of Prezygotic barriers
Habitat (prezygotic barrier)
when two species live in two different places preventing them to breed
Temporal (prezygotic barrier)
related insects separated/isolated because of season
behavioral (prezygotic barrier)
most important barrier w/animals. courtship and mate choice
mechanical (prezygotic barriers)
different species cannot mate and transfer sperm
gametic (prezygotic barrier)
important for externally fertilized animals. sperm and egg are not compatible
isolating mechanisms
prevent gene flow and prevent mating or union of sperm and egg
Postzygotic barriers
hybrid inviability
hybrid sterility
hybrid breakdown
hybric inviability
when zygote seperates and dies at gastula stage
hybrid sterility
often one sex is sterile
hybrid breakdown
1st generation is sterile
Phylogenetic Species Concept
based on evolutionary history
any cluster that includes a common ancestor and all decendants
evolution of reproductive isolation within an ancestral species
Another name for speciation
Modes of Speciation
Species get seperated, they adapt to new situation and environment and they come together again....but according to BSC they cannot breed
Sympatric speciation
seperation by ecological factors...ex:living in different trees/flowers
animal behavior
what an animal does and how it does it
2 components of behavior and examples
Genetic (nature)
* Innate behavior

Environmental (nurture)
* Learning
definition: innate behavior
developmentally fixed
e.g begging in nestling birds
definition: learning
behavior modified by experience
Is animal behavior Nature or Nurture?
Animal behavior is both nature and nurture
fixed action pattern
sequence of behavioral acts that is unchangeable
Explaination of an organism's success in life
some organisms do a little better than others it's not a live or die situation
Company comparison of living
organisms are like a company...everything they do has costs and benefits
"company profits"
# of offspring can be considered to this in the company organism analogy
company balance sheet
fitness can be compared to this in the organism company analogy
Types of interactions
def: coorperation
actor benefits & recipient benefits
def: selfish
actor benefits & recipient is harmed
def: spite
actor is harmed & recipient is harmed
def: Altruism
actor is harmed & recipient is benefited
def: social interactions
interactions between individuals of the same species
Hypothesis for evolution of altruism
Individual advantage
Kin selection
Reciprocal altruism
def: and founder of Kin selection
average proportion of genes of individual A that are present also in individaul B.

W.D Hamilton 1964
Kin selection
natural selection based on indirect fitness gains
2 components of fitness
Direct and Indirect fitness
def: direct fitness
personal reproduction
def: indirect fitness
additional reproduction by relatives made possible by an individual's actions