Ch 8

Question 1

what is the name for Dino bird

Answer 1

archaeopteryx
its a transitional form

Question 2

what are two theories of evolutionary patterns

Answer 2

gradualism- slow and steady divergence of lineages at an even pace
punctuated equilibrium - states that species remain fairly stable for ling periods of time but may swiftly change into new species in response to rapid environmental changes

Question 3

what is the evidence for the theory of evolution

Answer 3

comparative genomics (molecular evidence)
the fossil record
comparative anatomy and embryology

Question 4

how can evolutionary relationships be represented

Answer 4

phylogenetic trees

Question 5

what is the main source of genetic variation

Answer 5

mutations introduce new alleles into a population

Question 6

how long has life existed on earth

Answer 6

around 3.5 billion yrs

Question 7

what are fossils

Answer 7

presserved remains and impressions of organisms

Question 8

how does fossilisation occur

Answer 8

organic matter must be deposited and covered in sediment in an anoxic environment

Question 9

what’s petrification

Answer 9

common in plants – the original plant material is partly dissolved and some tissue is replaced with dissolved salts – turning it into rock

Question 10

what’s comparative dating

Answer 10

also down as relative dating, it determines the age of a rock/fossil, relative to other rocks/fossils found nearby

Question 10

what’s absolute dating?

Answer 10

the age of a fossil or rock in numerable form (assigns years)

Question 11

what are the three types of absolute dating?

Answer 11

radiometric dating (Carbon dating)
electron spin resonance
luminiscence

Question 12

what’s radiometric dating

Answer 12

a method of dating by determining the proportions of radioactive isotopes present in a sample.
isotopes can be unstable and break down at a known rate while others are stable therefore by compairing the ratio of broken down elements from stable ones you can determine an objects age
the older the object measured, the greater the margin of error, accuracy is restricted to 12,000yrs

Question 13

true or false; fossils can be aged by carbon dating

Answer 13

false because fossils have been mineralised & the organic tissue has been chemically replaced and fossilisation takes longer to occur than the maximum age of accuracy for C-14

Question 14

what’s Electron Spin Resonance do

Answer 14

measures the properties of electrons in the minerals of crystals

Question 15

how does Electron Spin Resonance work

Answer 15

electrons become trapped within the crystal lattice and are mildly magnetic
radiation increases over time and can be measured

Question 16

what are the concepts of divergent evolution, adaptive radiation, convergent evolution and parallel evolution

Answer 16

patterns of evolution

Question 17

what is adaptive radiation

Answer 17

rapid divergence of an evolutionary lineage from a recent common ancestor e.g. Darwins finches

Question 18

what is evidence of adaptive radiation

Answer 18

a cluster of related species

Question 19

what is parallel evolution

Answer 19

occurs when related species evolve similar features independently

Question 20

why do some organisms undergo parallel evolution

Answer 20

the organisms are filling similar ecological niches in similar environments but perhaps on the other side of the world, so adaptations were selected

Question 21

what’s mutation rate

Answer 21

the frequency of neutral mutations arising within a species is fairly constant

Question 22

how can you find when two organisms diverged from each other?

Answer 22

using mutation rate, because mutation rate is constant estimates on divergence to be made

Question 23

what’s bioinformatics

Answer 23

the digital storage, retrieval, organisation & analysis of biological data

Question 24

how is embryology proof of evolution

Answer 24

can establish evolutionary relationships based on structural similarities & differences of the developing embryo

Question 25

what’s Luminescence in terms of dating

Answer 25

properties are measured in minerals in sedimentary rock
optical luminescence – measures the light emitted when a mineral is exposed to visible light
thermoluminescence – measures light emitted from a mineral when heated