Exam 1 Review Flashcards
1
Q
What is evolution?
A
Descent with modification
2
Q
Who were the researchers and scientists that played a role in Darwin’s life?
A
-Charles Lyell
-Thomas Malthus
-Jean Baptise Lanmark
3
Q
Accomplishments of Jean Baptise Lanmark?
A
-Organisms that use 1 part of the body will strengthen it/dissuse weakens
4
Q
Accomplishments of Charles Lyell
A
-Renewed uniformitarism
-Earth was more than 6K years old
5
Q
Accomplishments of Thomas Malthus
A
-Many things will limit the human population
-Not indiv. in a population are the same
-More indiv. are born than survive
6
Q
Who were Darwin’s mentors that helped him develop Evolution by natural
selection?
A
-Charles Lyell
-Thomas Malthus
7
Q
What discoveries did Darwin make on his trip on the Beagle?
A
-Theory of natural selection
-Diversity of life
-Fossils
-Finches (beaks)
8
Q
Who was Alfred Russell Wallace?
A
Coauthor of Darwin’s book of Orgin of Life
9
Q
Describe why Darwin waited so long to publish his findings
A
-Workload
-Collab w/ Wallace
-Extensive research
10
Q
Describe Darwin’s theory of how evolution can occur
A
Indiv. w/ advantageous traits survive and pass on their genes leading to gradual changes in a population
11
Q
Describe the three criteria that need to be present for evolution to occur according to
Darwin’s theory.
A
-Variation: variety
-Heredity: be able to be passed on
-Selection: survival and reproduction
12
Q
Describe the outcome of natural selection on populations of organisms
A
Organisms become better adapted to their environment
13
Q
How does Natural selection lead to adaptation?
A
Surviving indiv. have their traits be reproduced that adapt to the environment
14
Q
What is a gene pool?
A
All of the genes in a population
15
Q
What is a population?
A
a group of organisms of the same species that live in the same area.
16
Q
At what level does Evolution act?
A
Population
17
Q
At what level does natural selection act?
A
Individual
18
Q
What is the difference between Natural selection and Evolution?
A
Natural selection is the mechanism/cause of evolution
19
Q
what an SNP
A
Single Nucleotide Polymorophism
20
Q
how SNP contributes to variation in the human population
A
Diversify human genotypes
21
Q
What is a polymorphism?
A
Multiple distinct form/phenotypes within a single species
22
Q
How does polymorphism contribute to variation of a trait in a population?
A
Allowing for multiple different forms or alleles of a gene
ex. Human blood types
23
Q
Describe the conditions needed for a population to be in Hardy-Weinberg equilibrium
A
-No mutations
-Random mating
-No natural selection
-Large population size
-No gene flow
23
Q
What does it mean for a population to be in H-W Equilibrium?
A
Variation remain constant
24
What does it mean if a population is in disequilibrium?
The allele freq. within that population are not stable & changing overtime
25
p
Freq. of allele dominant
26
q
Freq. of allele recessive
27
p^2
Freq. of homozygous dominant
28
q^2
Freq. of homozygous recessive
29
2pq
Freq. of heterozygous
30
Mechanisms involved in the microevolution of
populations
Natural selection
Genetic drift
Mutation
Gene flow
31
Is there evidence for microevolution occurring today or in the recent past
Yes, like human evolution, pesticides resistant insects, etc.
32
Does natural selection lead to perfect organisms?
NO
33
What is fitness?
Organism's ability to pass its genetic material to its offspring
34
What are the different mechanisms involved in Natural Selection?
-Variation
-Inheritance
-Selection
-Time and Adaptation
35
What is involved in sexual selection
Intrasexual selection: Opposite sex choose their mate
Intersexual selection: The same sex compete to mate with opp. sex
36
What is sexual dimorphism?
Sexes of the same species have different physical characteristics.
37
Describe why females are usually the more choosy sex
-Females are more choosy bc they carry the offspring
38
What is runaway selection?
One sex has exaggerated traits due to the strong prefernce of the other sex
ex. Peacock tails
39
What is a honest signal?
They reliably convey useful information to the receiver
40
What is balancing selection?
favoring multiple alleles at a particular gene locus, preventing any single allele from becoming dominant
41
What are the two types of balancing selection?
-Heterozygote advantage
-Frequency-dependent selection
42
Heterozygote advantage & correlation to balancing selection.
Heterozygotes are the fittest
-leads to genetic diversity
43
Frequency dependent
selection and how they contribute to balancing selection
Fitness of the genotype /phenotype depends on the composition of the population
-genetic variation
44
What are the different types of genetic drift?
-Bottleneck effect
-Founder effect
45
Describe what it means for an allele to become fixed in a population
An allele that is only variant that exist for that gene in a population
46
Describe how migration and its role as a mechanism for evolutionary change?
Provides mutation which creates ecolutionary change
46
Describe bidirectional migration and how it affects populations
Movement of cells/organisms in 2 direction
-genetic diversity
47
Describe the process of nonrandom mating
Reproductive process where organisms choose their mates
48
Describe what assortative mating is and how it can affect evolutionary change.
Nonrandom mating
49
What can be a result of nonrandom mating?
A change in genotype freq. within a population
50
How does inbreeding affect populations?
Reduce genetic diversity and the fitness of a population, which can lead to extinction
51
What is inbreeding depression? How does it affect the fitness of a population?
Reduced fitness and survival rates observed in offspring
-Increase the expression of harmful recessive alleles
52
What are some of the biases that are inherent in the fossil record?
Habitat bias: Organism that live in a place that other orgs. that were fossilized will fossil
53
Relative Dating
A method determining approximate age of a geological structure
53
Absolute Dating
A method determining exact age of a geological structure
54
What is Carbon-14 useful in dating?
Wood, plants, or bone
55
Radioactive Dating
Determine the age of organic materials as old as 60K years
56
What is Biogeography?
deals with the geographical distribution of plants and animals.
57
What is Wallace’s line?
Hypothetical boundary that separates Asia and Austrialia
58
Why are Islands considered a great source of evidence for evolution of species?
Adaptive radiation
59
How did Darwin use artificial selection to provide evidence for the process of evolution?
Through the observation of observable changes over short time periods, directed evolution, and the genetic basis of traits
60
61
Provide evidence of the process of evolution.
-Molecular biology
-Fossil records
62
How does antibiotic resistance occur in bacteria?
Bacteria develop genetic mutations that allow them to evade the effects of an antibiotic
63
Convergent evolution
When unrelated organisms evolve similar traits/behaviors to adapt to similar environments
64
Analogous Structure
Different species have evolved similar structures that perform the same function
65
Homologus
Having similar or corresponding features
66
vestigial structures
Features from the shared ancestors
ex. wisdom teeth, body hair
66
Developmental homologies
similarities in the embryonic development of different organisms
67
Evo-Devo/evolutionary developmental biology
The study of how changes in embryonic development lead to evolutionary changes in adult organisms
68
What happens when mutations arise that affect timing of development of different
structures?
Variety of phenotypic changes
ex. malformations
69
69
How do changes in Homeotic genes affect development?
Altering the identity of body segments, leading to the formation of incorrect structures in the wrong locations
70
What are Hox genes?
Master control genes; blueprints of the animals anatomy make up
71
What are Pax6 genes?
Controls many aspects of eye development before birth
72
How can changes in these homeotic genes affect the development of different types of eyes?
Alerting the spatial and temporal expression patterns of key genes responsible of the eye
73
What is Heterochrony?
Genetically controlled difference in the timing, or duration of a developmental process in an organism compared to its ancestors or other organisms.
74
Give examples of changes in the rate and timing of development that have led to substantial evolutionary change
-Flightless birds
-T. Rex small arms
-Paedomorphosis
75
What is Paedomorphosis?
Organism retains juvenile features into adulthood
75
How does studying development and genetics lead to finding out the evolutionary
history and common ancestors of species?
Identifies common ancestor of species by DNA sequence and development patterns
76
How do we use molecular genetics evidence to develop evolutionary relatedness/
lineages of different species?
Comparing DNA sequences of different species
77
What are molecular clocks?
Measures the number of changes/mutations, which accumulate in the gene sequences of different species over time
78
How do molecular clocks describe the evolution of species?
putting a series of evolutionary events into chronological order
79
What does macroevolution lead to?
A new species
80
Compare and contrast Microevolution and Macroevolution
Mirco: small-scale generation to generation
Macro: Large scale long period
81
Biological species concept
A species taxon as a group of organisms that can successfully interbreed and produce fertile offspring
81
What a species is?
Group of organisms that can reproduce w/ one another and create fertile offspring
82
Define reproductive isolation
The inability of a species to breed successfully with related species
83
Taxon
Any unit used in the science of biological classification
84
prezygotic isolation
Prevention of species forming zygote (before fertilization)
84
Describe the different mechanisms involved in reproduction isolation
-Prezygotic barrier
-Postzygotic barrier
85
Postzygote isolation
Reduces zygotes viabillity/ offspring w/ low fitness
85
Are there any instances where a hybrid would be fertile and able to produce viable
offspring?
Yes like rodents, wolves, etc.
86
How could two different species produce an offspring that is fertile and robust enough to
reproduce themselves?
Hybrid speciation/polyploidy
87
What is speciation?
how a new kind of plant or animal species is created
87
cladogenesis
evolutionary splitting of a parent species into two distinct species, forming a clade.
88
anagenesis
species formation without branching of the evolutionary line of descent
ex. fossil records of humans
89
What are the two types of speciation?
-Allopatric speciation
-Sympatric speciation
89
allopatric speciation.
two separate groups that are isolated from one another by geographic barrier
90
How does adaptive radiation lead to new species?
a single ancestral species to rapidly diversify into multiple new forms
ex.lizards
91
How does sympatric speciation occur in plants?
polyploidy; leading to reproductive isolation from the original population as it can only reproduce with other polyploid individuals,
92
Describe how sympatric speciation can occur in animals? and ex.
when a new species evolves within the same geographic area as the original population,
ex. Cichlid fish in African lakes
93
Describe the three different outcomes that can occur when two different species come
in contact within a hybrid zone.
1. reinforcement (no hybrids)
2. fusion (hybrids w/ no pressure)
3. stability (hybrids but still like parents)
94
How do mass extinctions lead to adaptive radiation?
many habitats are no longer inhabited by organisms because they have gone extinct
94
What are hybrid zones?
areas where genetically distinct populations meet, mate, and leave offspring of mixed ancestry
94
What are the competing hypotheses for how biological molecules first appeared?
-RNA World; RNA molecules
-Panspermia; Organic molecules
-Hydrothermal vent;deep-sea hydrothermal vents
-Oparin-Haldane; rganic molecules formed in the primitive Earth's atmosphere
94
Describe the two different hypotheses on the pace of evolution.
-Gradualism (slow rate over time)
-Punctuated equilibrium (rapid -> long period of stability)
95
What evidence is there for the Spontaneous formation of organic molecules? What was
the famous experiment and what did they conclude?
-Miller-Urey experiment
96
What is the significance of the Miller-Urey experiment?
first evidence that organic molecules needed for life could be formed from inorganic components
97
How do they think organic polymer first formed?
lightning sparked chemical reactions in Earth's early atmosphere
98
What is the RNA world hypothesis?
RNA molecules were the primary functional molecules
99
How do they think the first cellular-type structure formed? What polymer was involved in forming membranes?
-simple organic molecules, like RNA, became enclosed within a lipid membrane
-polysulfone (PSf)
100
What are protobionts? What are their characteristics?
spherical collection of lipids proposed as a rudimentary precursor to cells during the origin of life.
-self organized, spherical, collects lipids
101
What is the first macromolecule believe to be enclosed in a protobiont?
RNA
102
What has influenced the presence of life on the planet over the last 4.5 billion years?
It has gone from a molten ball of elements to a layered rocky planet
103
What events have occurred over geologic time that has influenced the type of life and
distribution of life on the planet?
continental drift, mass extinctions, climate change, volcanic eruptions
104
When did Eukaryotes first appear in the fossil record?
What eon did Eukaryotes first appear?
-around 2 billion years ago
-Proterozoic Eon
104
When did Vascular plants make an appearance in the fossil record?
Sulirian period
105
What are the major Mass extinction events that have occurred?
-Ordovician-Silurian extinction
-Late Devonian extinction
-the Permian-Triassic extinction
-the Triassic-Jurassic extinction
-Cretaceous-Paleogene (K-Pg) extinction
106
What occurs after a mass extinction?
biodiversity is greatly decreased, and it stays low during a "survival interval" before beginning to climb again
107
What era did Hominids first appear?
Miocene epoch
108
What key event lead the way for mammals to become the dominant animal on
the planet?
mass extinction of the dinosaurs
109
Who where our ancestors in the hominin line?
-Sahelanthropus tchadensis
-Australopithecus afarensis
-Homo habilis
- Homo erectus
-Homo heidelbergensis
110
Characteristics of Ordovician Period
-sea had many algae
-jawless fish, 1st verterbrate to leave fossil evidence
-ended in mass extinction that killed marine inverterbrates
111
Characteristics of Silurian Period
-Vasular plants evolved
-plants longer than their ancestors
-fishes w/ jaws & freshwater fishes arose(jawless fish still on top tho)
112
Characteristics of Devonian Period
Age of Fishes
-Seas had more life than land
-lobe-finned fishes
-mass extinction hurted marine life most
113
Characteristics of Carboniferous Period
Age of Amphibians
-amphibians were 9 meters long
-reptiles were born
-swamps became coal beds after extinction
114
Characteristics of Cambrian Period
-rapid explosion of diverse animal life forms in the oceans
-rise of animals with hard shells (more fossilized animals)
115
Characteristics of Permian Period
-last period of Paleozoic
-foreshadowed the dawn of dinosaurs
-mass extinction ended 90% of marine life
