Evolution and taxonomy

Question 1

3 domains

Answer 1

Bacteria, archaebacteria, eukarya

Question 2

Bacteria

Answer 2

Prokaryotes, ester links plasma membrane lipids

Question 3

Archaebacteria

Answer 3

Prokaryotes, ether links plasma membrane lipids

Question 4

Eukarya

Answer 4

Eukaryotes, ester links plasma membrane lipids

Question 5

Darwin’s main propositions in 1859

Answer 5

1. Random, heritable variation between species
2. Variation occurs randomly
3. Large abrupt changes are rare
4. Small variations make more suited for environment are maintained and increase frequency
5. Limited resources = survival of the fittest

Question 6

Weaknesses of Darwin’s propositions

Answer 6

Weaknesses of Darwin’s propositions Time is needed for evolutionary change, nut teacart s 4500 MYA old
Heritability mechanisms unknown

Question 7

Evidence for Darwin’s propositions

Answer 7

1. Artificial selection
2. Ecological genetics e.g. peppered moth
3. Rapid effects of artificial selection e.g. antibacterial resistance
4. Experimental synthesis of new species
5. Molecular phylogenetic evidence
6. Biogeographical evidence - plate tectonics and continental drift
7. Fossil record

Question 8

Mechanisms for evolutionary change

Answer 8

1. Mutations
2. Gene flow between populations
3. Genetic drift (random changes in allele frequency): founder effect, bottleneck
4. Non-random mating e.g. sexual selection

Question 9

Stabilisation forces

Answer 9

1. Stabilising selection e.g. human birth weight
2. Directional selection e.g. TXX in gartner snakes protects toxin in newt prey
3. Disruptive selection - favour in different directions

Question 10

Species isolating mechanisms

Answer 10

Ecological - spacial and temporal (pre mating)

Reproductive - permeating (teportal, ethological mechanical) and postmating (prezyogitic and pos-zygotic)

Question 11

Speciation

Answer 11

1. Allopatric - geographical isolation
2. Sympatric - reproductive isolation
3. Parametric - on edge of species range

Question 12

Panmaxis

Answer 12

Fully random mating (unlikely)

Question 13

Interbreedng

Answer 13

Self fertilisation or cross fertilisation of closely relayed

Question 14

Outbreeding

Answer 14

Higher inter breeding levels

Question 15

Polymorphic phenotypes

Answer 15

Change in local phenotype - different local environment and selection pressures

Question 16

Polyploidy

Answer 16

Changes in chromosome completes AA => AAA

Question 17

Hadean

Answer 17

3800 MYA, high tops, v high CO2, water, no life, organic molecules

Question 18

Archean

Answer 18

The beginning - 3800-2500 MYA, much ocean, v high CO2, negligible oxygen. First prokaryotes with self rep all marine. Photosynthetic cyanobacteria generate oxygen.

Question 19

Proterozoic

Answer 19

2500-542 MYA, oxygen deposits build up further, marine eukaryotes 1500 MYA,

Question 20

Cambrian

Answer 20

542-488 MYA, oxygen levels similar to today, rapid diversification, almost entirely marine (cambrian explosion), earliest vertebrates

Question 21

Ordovican

Answer 21

488-444 MYA, massive glaciers over Gondwanaland, drop sea level - 75% animal species extinct

Question 22

Silurian

Answer 22

444-416 MYA, marine life recovered, jawless fish, first terrestrial vascular plants and arthropods

Question 23

Devonian

Answer 23

416-259 MYA, Most jawless fish extinct, mass extinction of text at end. Terrestrial plants more diverse. First tetrapods
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Question 24

Carboniferous

Answer 24

359-297 MYA, large glaciers, extensive swamp forests, diversity of terrestrial animals increased, flight evolved in insects

Question 25

Permian

Answer 25

297-251 MYA, Pangea, diverse fauna, lineage leading to mammals, most dramatic animal extinction at end, volcanic activity and decline in o2 

Question 26

Triassic

Answer 26

251-200 MYA, pangea separates, o2 rises, diversification. Mass extinction, possibly due to meteorite

Question 27

Jurassic

Answer 27

Jurassic 200-145 MYA, early mammals, birds at end. Dinosaurs specialised, many could relate body temp, flight evolved separately in pterosaur reptiles and birds

Question 28

Cretaceous

Answer 28

145-65 MYA, high sea levels, warm and humid, increase diversity, first flowering plants, mass extinction - massive environmental change, possible due to meteorite 

Question 29

Tertiary

Answer 29

65-1.8 MYA, continental similar to today, first hot and humid then cooler and drier

Question 30

Quaternaruy

Answer 30

1.8 MYA - dramatic cooling and climate fluctuations, 4 major ice ages

Question 31

Classification

Answer 31

The way organisms are sorted into taxa

Question 32

Systematics

Answer 32

Grouping species according to evolutional ancestory

Question 33

Phylogeny

Answer 33

Evolution history of a group of organisms

Question 34

Order of taxa

Answer 34

Domain, kingdom, division/phylum, class, order, family, gents, species, subspecies, variety, form 

Question 35

Monophyletic

Answer 35

All living descendants of a single ancestor

Question 36

Polyphyletic

Answer 36

Descendants for several different ancestors

Question 37

Paraphyletic

Answer 37

Basis of non-specilast or non-unique characters