CH 20.

Question 1

systematics

Answer 1

study of phylogenetic relationships

Question 2

monophyletic taxa

Answer 2

each taxon includes ancestor and all descendants

Question 3

paraphyletic taxon

Answer 3

leaves out a common descendant, No crazy uncle

Question 4

polyphyletic taxon

Answer 4

includes species with different ancestors (blood family reunion + in law)

Question 5

cladistics

Answer 5

method of determining phylogeny, identifies homologous characters in a group as ancestral or derived

Question 6

plesiomorphy

Answer 6

homologous charactesr shared with ancestor, (trait that is inherited from a common ancestor and is shared by multiple species within a group)

Question 7

snyaptomorphy

Answer 7

novel or evolved shared character different from ancestor

Question 8

autapomorphy

Answer 8

derived and unique, unique to a given taxon. That is, it is found only in one taxon, but not found in any others or outgroup taxa

Question 9

maximum parsimony

Answer 9

choose best tree with fewest evolutionary events

Question 10

calde

Answer 10

all the species on a branch, share homologies

Question 11

true of false, we can infer the sequence of evolutionary events from cladistic trees (but not absolute time)

Answer 11

ture

Question 12

orthologous genes

Answer 12

inherited from common ancestor, encode very similar proteins with same function in both species (2+ species have same/similar gene with same function), a gene in different species that evolved from a common ancestor by speciation

Question 13

more DNA differences =

Answer 13

more time elapsed since two groups diverged, less closely related (have had more time to accumulate mutations)

Question 14

shared sequences are

Answer 14

homologous

Question 15

molecular clocks estimate

Answer 15

divergence times, assumes constant rate of homologous DNA mutations, calibrated with known fossil ages

Question 16

LUCA

Answer 16

last universal common ancestor

Question 17

root of tree is complicated bc of

Answer 17

horizontal gene transfer (mitochondria and chloroplasts), gene transfer between first cells, domain eukarya all have mitochondria, transfer genetic material BETWEEN species

Question 18

Hadeon Eon

Answer 18

molten rock surface no liquid water

Question 19

archeon

Answer 19

crust cooled and solidified, formed global ocean from condensed water, volcanoes created first land, low O2 in atmosphere, first life (prokaryotic cells)

Question 20

plate tectonics

Answer 20

crust breaks into moving plates

Question 21

oxygen revolution

Answer 21

photosynthesis by prokaryotes made seas and atmosphere O2 rich, more successful bc more energy

Question 22

proterozoic eon

Answer 22

continents form as islands merge, created areas of shadow seas, ice and glaciers, eukaryotic life began

Question 23

mesozoic era

Answer 23

cretaceous mass extinction, dinosaurs bye