Chapter 13 Flashcards
Who influential book entitled On the Origin of Species by Means of Natural Selection.
Charlies Darwin
Over generations, individuals with the best functioning traits are consistently selected, _________________ are produced.
Evolutionary adaptation
Darwin predicted _____________ to have existed between species.
Numerous intermediate
Darwin was aboard the HMS beagle he collected numerous specimens by doing this he found that.
many of the Galapagos species resembled those in South America, but showed some variation
Darwin was strongly influenced by the writing of geologist ____________, who promoted the idea of an ancient Earth.
Charles Lyell
Darwin became convinced that the Earth was very old, had been shaped by ____ _______, and continues to change even today.
Slow processes
All organisms inhabiting Earth today are derived from ______________that may have looked differently
Ancestral species
All organisms inhabiting Earth today are derived from ancestral species that may have looked differently, by the mechanism by which this is accomplished is _______________.
Natural selection
As organisms reproduce, they can have a variety of offspring. Those offspring best fit for their environment are most fit to _________ and _______.
Survive
Reproduce
What are some evidences commonly used to support evolution.
- Fossils
- Biogeography
- comparative anatomy and embryology
- Molecular biology
What are fossils?
Fossils are remnants of organisms that lived in the past that have been turned to stone
What can fossils include?
- Plants
- animals
- impressions
- bones
- soft tissues.
What type of rock is most likely to find fossilization?
Sedimentary rock
What can fossil be often used for?
To compare anatomy with extinct organisms with extant ones
what is interpreted as chronology of fossils embedded in rock layers of different ages.
the fossil record
Fossil records are used to show that organism appeared in a ________________.
Historical sequence
Older more primitive organisms at the ______.. and ____ more advanced organisms at the top.
Bottom
New
___________ is the study of the geographic distribution of species.
Biogeography
____________ then explains that organisms must have characteristics to live in a particular environment
Natural selection
_____________ is the comparison of body structure between different species
Comparative anatomy
_________ is the similarity of structure due to common ancestry.
homology
___________ became modified to under a new function
Ancestral structures
__________ is the similarity of structures based on function, but does not share common ancestry.
Analogy
Forelimbs of mammals are constructed from the same skeletal element, because they are interpreted as sharing a common ancestor they are considered __________
Homologous
________________ is the comparison of structures that appear similar during the development of different organisms.
Comparative embryology
During early embrology, some vertebrates look similar, implying they have very similar features, which may indicate ______________.
Common ancestry
Molecular biology of organisms is also used to show _____________ among species.
Evolutionary relationships
___________ can be used to determine how distantly (or closely) organisms are related.
DNA squences
The more similar one’s DNA is to an organism, the more likely that they are _________.
Closely related
The less similar one’s DNA is to an organism, they are more likely _______________.
Distantly related.
The similarity between human and chimpanzee DNA is _______.
~98%
Chimpanzees and humans have the most _____________ of humans with any species.
Similar genetic match
Darwins Galapagos finches are an example of _________ as a result of __________.
Adaptive evolution
Natural selection
Evolutionary biologist indicated that any close evolutionary relationship to humans is due to
similar genetics
All the individuals in a population have ___________________.
slightly different characteristics
for example Lady bugs
Much of this variation is _______, and passed down from generation to generation.
Heritable
Individuals with less reproductive success die, therefor they do ______________.
Not reproduce
Only those individuals with traits best suited for their environment are more likely to survive, and _________________________________.
reproduce, leaving a greater number of offsprings
What are some examples of natural selections.
- Pesticide resistance in insects
- Development of antibiotic-resistant bacteria
Insects with a resistance to pesticides, will be the ones ___________________________.
more likely to survive and reproduce
Consistent use of antibiotics can select for antibiotic resistant strains of bacteria that are ___________.
difficult to treat
A ________ is a group of individuals of the same species living in the same area at the same time.
Population
Because variance amongst individuals must be present to select from, populations _________________.
are the smallest biological unit that can evolve.
Population geneticists investigate the fate of populations as _____________.
evolutionary units
When tracking the genetic makeup of a populations over time this allows us to do what?
allows us to determine whether a population is evolving and how fast it is changing
Although there is a lot of variation among individuals of a population differences in _________________.
Genetic components
Mutations are random ___________ of an organism
Changes in the DNA
Most mutations are deleterious, but sometimes they are considered to be _______.
beneficial
Sexual recombination shuffles and distributes genetic material during ______ divisions
Meiotic
DNA containing these mutations can then be passed from a ____ to an _____.
Parent
Offspring
The gene pool includes all versions of all _____ in all individuals making up a population.
Genes
The gene pool is the collective _____ of the population.
Genomes
The dominant allele in the population is symbolized by the letter
p
The recessive allele in the population is symbolized by the letter
q
Together the dominant allele and the recessive allele can be symbolized as
p+q=1
p^2
Homozygous dominant
2qp
Heterozygous
q^2
homozygous recessive
How is the Hardy Weinburg expressed?
p^2+2pq+q^2=1
What does the Hardy-Weinburg equation represent?
is a mathematical representation of a gene pool
The Hardy-Weinburg equation adds up all of ______ in population and is used to determine expected _______ of the next generation.
Genotypes
Phenotypes
If the Hardy-Weinberg equation is in equilibruim, this describes a __-___ population that is in genetic stasis (not changing over time)
Non-evolving
When the hardy-weinberg equation is not in equilibrium, the allele frequencies continually change over time, and the population is undergoing small scale evolution called _____________.
microevolution
P=
Sum of total alleles for a given gene in the population
q=
Sum of total alleles for a given gene in the population
If a locus has two alleles, W and w there could be three possible genotypes:
WW, Ww, and ww.
The frequency of all three genotypes must be __ or ___
100% or 1.0
p^2 + 2pq + q^2 =
100% or 1.0
Homozygous dominant (p^2) + heterzygous (2pq) + homozygous recessive (q^2)
=100%
_______ is measured by changes in allele frequency in a population.
Microevolution
Mechanisms of microevolution include
Genetic drift
gene flow
mutations
natural selection
__________ is a change in the gene pool of a small population due to chance.
Genetic drift
The bottleneck effect is an example of ______.
genetic drift
The bottle neck effect results from a drastic reduction in population size and therefore a reduction in the genetic variation because this limits the __________ to select from
Possible genes
The_______ Is genetic drift in a new colony
Founder effect
The founder effect explains why certain unusual alleles (such as genetic disorders among humans) are expressed more frequently in populations founded by only____ indiviuals than in the original, ____ population
Few
large
When population regularly or irregularly exchange genetic material, this is called_______.
gene flow
The ____ of genetic material from other populations will reduce the genetic differences between population.
Influx
________ are permanent changes in an organisms genome.
mutations
A single mutation in a single organism ordinarily will not have an impact on a large population since most ______________.
Mutations are lethal
A mutation that is beneficial during periods of environmental stress, however can make the difference between _____ and _____.
Survival
death
_________ is the contribution an individual make to the gene pool of the next generation relative to contribution of others with that population.
Relative fitness
The number of offspring is away to determine ______.
fitness
zero offspring =
zero fitness
During ______ the phenotype of a population is shifted.
Directional selection
Directional selection favors a more _______ phenotype, shifting alleles in a population.
Extreme
During ___________ both extremes of phenotype are favored.
Disruptive selection
In disruptive selection the intermediate phenotype is not advantageous and its frequency becomes _________.
Reduced
During ________ the variation of a particular trait becomes limited
Stabilizing selection
In stabilizing selection the extreme trait values are not beneficial then the mean value is selected for.
,
what is sexual selection?
- is a form of natural selection
- in which individuals with certain characteristics are more likely than other individuals to obtain mates
In many animals species, males and females show distinctly different appearances called _______________.
sexual dimorphism
___________ (within the same sex) involves competition for mates, usually by males.
Intrasexual selection
