Chapter 14 - Evolution: Changes Over Time

Question 1

relative dating (stratigraphy)

Answer 1

the oldest layer of rock is at the bottom and progressively younger layers lie above it

Question 2

absolute dating

Answer 2

the age of the fossil is determined by use of methods such as radiometric dating
based on decay of certain radioactive elements

Question 3

fossils

Answer 3

the remains or impressions of previously existing organisms usually preserved in sedimentary rocks

Question 4

direct fossil evidence

Answer 4

bones, teeth, leaves and shells

Question 5

indirect fossil evidence

Answer 5

“trace fossils”

footprints, tracks, toothmarks, burrows

Question 6

biogeography

Answer 6

the study of plant and animal distribution

Question 7

homologous structures

Answer 7

structures that have similar basic structure even though they may serve different functions
common ancestor

Question 8

analogous structures

Answer 8

structures that carry out similar functions but are not necessarily similar in basic structure
convergence

Question 9

vestigial organs

Answer 9

organisms have degenerate organs/structures that no longer perform the function they did in their ancestors
kiwi wings

Question 10

comparative embryology

Answer 10

comparing the embryonic development of different vertebrates

Question 11

molecular homology

Answer 11

the similarity of the nucleotide sequences of DNA or RNA molecules or amino acid sequences

Question 12

DNA hybridisation

Answer 12

DNA unzipped and recombined to form hybrid DNA
heat used to seperate
more heat more related
cladogram

Question 13

DNA sequencing

Answer 13

the sequence of DNA can be determined with technology

Question 14

amino acid sequencing

Answer 14

similarity/difference between amino acid sequences of particular proteins
more differences less related

Question 15

immunological techniques

Answer 15

can be used to indirectly measure the degree of similarity of proteins in different species

Question 16

mtDNA

Answer 16

mitochondrial DNA

matrilineal patten of inheritance

Question 17

phylogeny

Answer 17

the evolutionary history of organisms represented in a cladogram

Question 18

allopatric speciation

Answer 18

the process of forming a new species

Question 19

steps of allopatric speciation

Answer 19

variation - range of characteristics
isolation - geographic barrier, no gene flow
selection - different selection pressures
speciation - changes accumulate, can’t interbreed

Question 20

convergent evolution

Answer 20

evolution that results in species that are of similar appearance that are not closely related
common selection pressures

Question 21

divergent evolution

Answer 21

the accumulation of differences between groups of an ancestral species
different selection pressures

Question 22

extinct

Answer 22

refers to a species of which no living members exist

Question 23

Conditions of fossilisation

Answer 23

Low oxygen
Low acidity
Rapid burial
Sediment covering