Evolution

Question 1

What is the general principle of evolutionary change?

Answer 1

Random mutations and recombination create genetic variation
Natural selection weeds out less desirable traits
Genetic drift and differentiation create reproductively isolated species that become new species

Question 2

Who is Lamarck?

Answer 2

Scientist believing in Lamarckist evolution; supported mechanistic causality; forms and functions of organisms change to math geology, adaptive evolution; environment changes and species follow; spontaneous forms to move toward perfect form (progression in linear order)

Question 3

Who is William Paley?

Answer 3

Author of Natural Theology; refutes formalism (function follows form), refutes structuralism (correlation among organs), homologies - common plans; adaptation towards functional species is the craft of God

Question 4

Who is Louis Agassiz?

Answer 4

God is in the hierarchical taxonomy of species; species the incarnations of the ideas of God; systematics show the though of the divine mind; support formalism; form does not fit function immediately

Question 5

Who is Charles Darwin?

Answer 5

Formalism; refinement and modification of the archetype; cycles of expansion and contraction; archetypes are adapted ancestors; intrinsic factors generate isotropic variation, directionless, acted on by natural selection; changes in ontogeny reflected in later growth; homologous parts vary together and tend to fuse or join; one part may impress form upon another; correlated variation in homologous and symmetrical structure

Question 6

What is formalism?

Answer 6

Directional, internal forces

Question 7

What is saltationism?

Answer 7

discontinuous evolution, channels are internally generated pathways, large jumps in form

Question 8

What is orthogenesis?

Answer 8

Directional evolution; evolution proceeds along defined and restricted pathways because internal factors limit and bias variation into specific channels

Question 9

What is modern synthesis?

Answer 9

Mendelian principles operate in all organisms; small scale Darwinian variability; selection pressures on genetic differences lead to evolutionary changes

Question 10

Who is Ronald Fischer?

Answer 10

began modern synthesis; combine Mendelian inheritance with Darwinian variation

Question 11

What is neutralism?

Answer 11

genetic variation is neutral and shaped by mutation and random genetic drift

Question 12

What is evo devo?

Answer 12

Evolutionary development; changes made in the growth or larval stage that cause change later

Question 13

What is prebiosis?

Answer 13

A high-temperature reducing atmosphere with lots of hydrogen atoms, CO2 and N2 with little oxygen; inorganic material with electrical discharge form organic compounds, combine into amino acids

Question 14

What is the iron-sulfur world theory?

Answer 14

energy releases from redox reaction of metal sulfides aid in synthesis of organic molecules, formation of oligomers, and formation of polymers

Question 15

What is compartmentalization?

Answer 15

first life evolve in caverns with sulfide walls on the ocean floor; steep temperatures are optimal areas for reactions; hydrothermal water provide constant flow of elements and energy

Question 16

What is a last universal common ancestor?

Answer 16

The last ancestor shared between all living things - the source of life before divergence occurred; most likely had a cell membrane, cell wall, and unicellular with DNA and RNA

Question 17

What is a phylogeny?

Answer 17

history of taxa that have successfully originated from common ancestors

Question 18

What is a clade?

Answer 18

A monophyletic group; derived from a single common ancestor

Question 19

What is parsimony?

Answer 19

a scientific rule that states that if there are two answers to a problem, if one answer must rewritten common laws of logic and science, the other answer and simpler is more likely correct

Question 20

What is a character?

Answer 20

a heritable trait possessed by an organism

Question 21

What is a derived character?

Answer 21

A character that is present in one or more in a clade but not all

Question 22

What are the similarities and differences between bacteria, archaea, and eukarya?

Answer 22

Bacteria - peptidoglycan cell walls; nucleoid or circular DNA; plasmids; coupled transcription-translation; operons; flagellum
Archaea - surface-layer proteins no peptidogylcan cell walls; flagellum; nucleoid or circular DNA; plasmids; operons; coupled transcription-translation; chromatin-like material with histone homologs in DNA; TATA promotors and bindign proteins in transcription; highly methyl-branched isoprenyl chains; ether linkages in cell membrane
Eukaryotes - diverse, membrane-bound nucleus, chromatin and histones, DNA, RNA , internal membranes and vesicles, mitochondria, chloroplasts, hydrogenososmes, cystoskeleton

Question 23

What is lateral recombination?

Answer 23

transfer from one organism to another
transformation - acquisition of DNA through environment through competence
conjugation - mating types pass a plasmid from one to another via pilus
Transduction - phage incorporates viral genome into host genome

Question 24

What is endosymbiosis?

Answer 24

mitochondria and chloroplasts derived from bacterial symbionts and incorporated into eukaryotic cells; change after to make necessary

Question 25

How did multicellularity arise?

Answer 25

1. Failure to separate after division

2. Accumulation from single0celled forms to an aggregate

Question 26

What are requirements of multicellularity?

Answer 26

Cells must recognize similar cells
Cells must attache to each other
Cells must develop a polarity
Polarized cells differentiation into different fates

Question 27

What is differentiation?

Answer 27

Production of specialized cell types that allow division of labor; special functions for special cells

Question 28

What challenges do terrestrial ecosystems pose to life evolving from aquatic ecosystems?

Answer 28

Gravity
Desiccation (holding water)
Respiration
Reproduction
Locomotion
Senses

Question 29

What is the difference between gradualism and punctualism?

Answer 29

Gradualism - steady change over time, lots of intermediates

Punctualism - rapid expansion with few or no intermediary forms

Question 30

How does extinction increase evolution?

Answer 30

Extinction of species create a niche hole that needs to be filled and new species with those skill sets can thrive in those situations and branch off from a common ancestor

Question 31

What are pseudogenes?

Answer 31

Appears as functional genes but have errors that prevent transcription; mutation or nearly-sense accumulations of sequences

Question 32

What are types of mutations?

Answer 32

Point mutations - one base pair substitution
-Transition (doesn’t change amino acid)
-Transversion (changes amino acid)
Synonymous - silent mutations
Frameshift - insertions and deletion produce new amino acid sequence

Question 33

What is artificial selection?

Answer 33

Traits acquired based on select breeding for desired traits

Question 34

What is iteroparity and semelparity?

Answer 34

Iteroparity - many reproductive events

Semelparity - singular reproductive event

Question 35

What is altruism?

Answer 35

Providing a benefit to another at a cost to oneself

Question 36

What is manipulation?

Answer 36

One species deceives another into assisting them at harm or no benefit to other species

Question 37

What is the biological species concept? What is the phylogenetic species concept?

Answer 37

biological - species defined by reproductive discontinuity

phylogenetic - species are sets of populations with character states that distinguish them

Question 38

How does reproductive isolation occur?

Answer 38

Ecological (habitat or season)
Behavioral (wrong actions)
Mechanical isolation (wrong parts)
Gametic isolation (cell surface receptors)
Hybrid inviability (won't work)
Sterility (cannot reproduce)

Question 39

What is the Dobzhansky-Muller two-locus model?

Answer 39

Ancestral species separates into two populations; mutation occur independently; some become fixed; may not be compatible with other population

Question 40

What are the costs of sexual reproduction?

Answer 40

1. Recombination may not be favorable
2. Syngamy and meiosis take longer, slower reproduction
3. Courtship and mating may be risky (predation, STDs)
4. Low populations - may not find mate
5. Females suffer genome dilution
   6, Selfish genes spread

Question 41

What is kin selection?

Answer 41

change in the frequency of an allele caused by the effect of that allele on the fitness of other individuals who carry the allele

Question 42

What is an operon?

Answer 42

A set of adjacent genes whose transcription is regulated as a single unit

Question 43

What is overdominance?

Answer 43

heterozygotes that have higher trait values (fitness) that either homozygote

Question 44

What is polyploidy?

Answer 44

A cell or chromosome carrying more than two genomes

Question 45

What is genetic drift?

Answer 45

random change in genotype frequency caused by variation in individual reproduction

Question 46

What is the RNA world?

Answer 46

stage before the evolution of genetic code when RNA was responsible for both heredity and catalysis

Question 47

What are the benefits of cooperation?

Answer 47

Reciprocity, protection of young and self from predation, ability to find resources, manipulation, kin selection

Question 48

What are the costs of cooperation?

Answer 48

May not get “favor” from others, larger numbers may attract predators, may not reproduce and spread own genes, reproductive success

Question 49

What are the parts of a phylogenetic tree?

Answer 49

Root - common ancestry
Branch - one area
Node - divergence
Clade - monophyletic group

Question 50

What are some problems in determining phylogenetic trees?

Answer 50

Common ancestry
Random mutations
Lateral transmission
Convergent evolution