Transcript Chapter 13 and 14 Review

Chapter 13 and 14
Review
Evolution Part I
How did Darwin develop his
theory of evolution?
 He traveled to the Galapagos and studied the animals
 He studied the fossil record
 He studied finches
 He studied adaptations and natural selection
 He read books
What is artificial selection?
 When humans choose what traits they want to pass on
and breed animals/plants selectively
What is the smallest unit that
evolves?
 A population
How can we tell if an
organism is “fit” to survive?
 It makes babies and passes on its genes
What does comparative
anatomy tell us about
evolution?
 Organisms that share anatomical structures evolved
from a common ancestor
What is a scientific theory?
 An idea or explanation that is supported by an
abundance of facts and evidence
How do we know if animals
are a different species?
 They cannot interbreed and produce fertile offspring
What is necessary for
allopatric speciation?
 When new species evolve because they were
separated by geographical isolation
What is taxonomy?
 The science of naming and classifying organisms
What is adaptive radiation?
 The evolution of numerous species from a single
ancestor
What is sympatric speciation?
 The appearance of a new species in the same area as
the parent population
 They are not separated by geographical barriers
If q2 is equal to 0.36, what is
2pq?
 q=0.6
 p=0.4
 2pq=0.48
If animals don’t breed
because of different mating
dances, what is this?
 Behavioral isolation
 Prezygotic barrier
What does comparative
embryology tell us about
evolution?
 Organisms that have similar embryos share a common
ancestor
Evidence of Pangaea comes
from the study of …
 biogeography
List and identify all 5 variables
of the H-W equation.
 p = frequency of the dominant allele (A)
 q = frequency of the recessive allele (a)
 q2 = frequency of homozygous recessive (aa)
 p2 = frequency of homozygous dominant (AA)
 2pq = frequency of heterozygous (Aa)
What are petrified trees and
ammonite casts?
 fossils
If p is equal to 0.6, what is q
equal to?
 0.4
 Because p+q=1
If p is equal to 0.5 and q is equal to 0.5,
what is the frequency of the heterozygous
genotype?
 Heterozygous is equal to 2pq
 So 2 x 0.5 x 0.5 is equal to 0.5 which is equal to 50%
If q is equal to 0.3, what is p?
 0.7
If p is equal to 0.8, what is the
frequency of the
heterozygous?
 p=0.8
 So q = 0.2
 Finding 2pq is 2 x 0.8 x 0.2
 So 2 x 0.16
 So it is equal to 0.32 or 32%
Does natural selection choose
the phenotype or genotype?
 The phenotype (like long necks) and then eventually
the genotypes change in the population
What are the conditions for HW equilibrium?
 Large population size
 Isolated population
 Random mating
 All individuals are equal in reproductive success
 There are no mutations
What is an example of
artificial selection?
 Breeding of dogs
 Breeding of broccoli and cauliflower from mustard
greens
What is the founder effect?
 When a new population is started by a few individuals
Give an example of a
postzygotic barrier
 Hybrid inviability
 Hybrid sterility
 Hybrid breakdown
What is the unifying theme of
biology?
 evolution
What are some types of
fossils?
 Bones
 Casts
 Petrified wood
 Organisms are preserved in ice
What are the 5 evidences of
evolution?
 Fossils
 Comparative anatomy
 Comparative embryology
 Molecular biology
 biogeography
Give an example of
comparative anatomy
 Our arm
 A bat wing
 A whale flipper
 A cat leg
What did Darwin conclude?
 Organisms who are the most fit survive and reproduce
 Populations produce more organisms than the environment
can support
 The Earth is very old
 Organisms compete for limited resources
 Acquired traits (cutting off an arm) are NOT passed on to
offspring
In the H-W equation, what is
p2? q2?
 Frequency of homozygous dominant individuals
 Frequency of homozygous recessive individuals
What is the bottleneck effect?
 When a disaster drastically reduces population size
Why are endangered species
genetically endangered?
 There is little genetic diversity and the populations are
more susceptible to diseases
List and explain all 5
prezygotic barriers.
 Temporal isolation: mating occurs at different times
 Habitat isolation: individuals live in different habitats
 Behavioral isolation: there is no sexual attraction
 Mechanical isolation: sex parts don’t fit
 Gametic isolation: egg and sperm don’t fit together
List and explain all 3
postzygotic barriers
 Hybrid inviability: hybrid zygotes don’t develop to
sexual maturity
 Hybrid sterility: hybrid babies are sterile, don’t produce
gametes
 Hybrid breakdown: offspring of hybrids are weak or
infertile
What is the difference
between sympatric and
allopatric speciation?
 Allopatric speciation occurs when there is geographical
isolation, sympatric does not
Does allopatric speciation
happen more often in small or
large populations?
 small
What is evolution?
 A scientific theory supported by an abundance of facts
and evidence that shows how species change over
time
How old is the Earth?
 4.6 billion years old
What animals are humans
related to?
 Apes, dogs, cats, fish, reptiles,
amphibians….everything!
If you need to find the frequency of the
heterozygous genotype, what do you
solve for?
 2pq
If you know q2, how do you
find q?
 Take the square root
If you know p, how do you
find q?
 Subtract p from 1
 p+q=1
 So 1-p = q
If you know q, how do you
find the frequency of the
heterozygous?
 First find p by doing 1-q
 Then do 2 x p x q
How much DNA do humans
and chimps share?
 98.5%
What does the H-W
equilibrium tell us?
 It shows that conditions in nature support evolution
 Equilibrium does not occur in nature
What 5 things can cause
evolution?
 Bottleneck effect
 Genetic drift
 Founder effect
 Gene flow
 Mutations
List the categories of
taxonomy from largest to
smallest.
 Kingdom
 Phylum
 Class
 Order
 Family
 Genus
 Species
What is survival of the fittest?
 Natural selection
 They way populations evolve