Ch1 key terms

Question 1

binomial nomenclature

Answer 1

2 names: a genus and a species name

Question 2

taxa

Answer 2

groups of organisms of any rank

Question 3

taxonomy

Answer 3

discipline that assigns names to organisms

Question 4

phylogeny

Answer 4

evolutionary relationships based on the branching sequences of lineages

Question 5

phylogenetic tree

Answer 5

a branching diagram depicting our hypotheses of evolutionary relationships among taxa

Question 6

root

Answer 6

base on the phylogenetic tree

Question 7

base

Answer 7

root of s phylogenetic tree

Question 8

node

Answer 8

branching point in a phylogenetic tree that leads to two or more terminal taxa

Question 9

terminal taxon

Answer 9

the group named at the tip of the branch of a phylogenetic tree (can be any taxonomic level)

Question 10

classification bracket

Answer 10

a bracket that indicates the taxa included in a group

Question 11

basal

Answer 11

taxa closer to the root of a particular phylogenetic tree

Question 12

derived

Answer 12

taxa that branch above the first node

Question 13

topology

Answer 13

arrangement of branches and taxa in a phylogenetic tree

Question 14

phylogenetic systematics

Answer 14

grouping of taxa according to their evolutionary relationships

Question 15

evolutionary lineage

Answer 15

an ancestor and all of its descendants; equivalent to clade and monophyletic group

Question 16

clade

Answer 16

a monophyletic groups that includes an ancestor and all its descendants

Question 17

monophyletic

Answer 17

describes a group that includes an ancestor and all of its descendants

Question 18

common ancestor

Answer 18

root

Question 19

paedomorphosis

Answer 19

retention of larval or juvenile characteristics into adult life

Question 20

eras

Answer 20

3 major divisions of time in Earth history

Question 21

sister group (sister taxon)

Answer 21

monophyletic lineage most closely related to the monophyletic lineage

Question 22

crown group

Answer 22

outgroup

Question 23

paraphyletic

Answer 23

group of organisms that does not include an ancestor and all its descendants (names will be written in “quotation”)

Question 24

parsimony

Answer 24

(most parsimonious phylogeny )the branching sequence that requires the fewest changes to go from the ancestral condition to the derived condition

Question 25

modern synthesis

Answer 25

a view of evolution combining information from genetics, natural selection, and population biology that emerged in the mid twentieth century

Question 26

apomorphy

Answer 26

a character that has changed from its ancestral state (a derived character)

Question 27

synapomorphy

Answer 27

a derived character (changed from its ancestral state) shared by 2 or more taxa

Question 28

plesiomorphies

Answer 28

characters that are unchanged from their ancestral conditions

Question 29

molecular scaffolding

Answer 29

using molecular data to determine the branching pattern of phylogenies and morphological data to date the branching

Question 29

ingroup

Answer 29

evolutionary group under study

Question 29

outgroup

Answer 29

a reference group that is less closely related to the ingroup than the members of the ingroup are related to each other

Question 30

extant phylogenetic bracket

Answer 30

using the character states of 2 extant lineages to infer the character states of extinct taxa that lie between the extant taxa in a phlogeny

Question 31

stem group

Answer 31

extinct forms in a clade that lack some of the derived characters that define the crown group

Question 32

alleles

Answer 32

forms of a gene that differ in their DNA base sequence

Question 33

darwinian fitness

Answer 33

genetic contribuation of an indivual to succeeding gen

Question 34

positive selection

Answer 34

an increase in the frequency of a genetically based trait in successive generations

Question 35

signal cascades

Answer 35

intracellular pathways that can be triggered by extracellular molecules to either activate or repress gene expression

Question 36

gene families

Answer 36

genes that produce structurally related forms of the same protein

Question 37

convergent evolution

Answer 37

independent evolution of similar traits or types of organisms often in relation to biogeographic isolation