Chapter 26

Question 1

phylogeny

Answer 1

the evolutionary history of a species or group of related species

Question 2

systematics

Answer 2

classifies organisms and determines their evolutionary relationships
-use fossil, molecular, and genetic data to infer evolutionary relationships

Question 3

taxonomy

Answer 3

the ordered division and naming of organisms

Question 4

binomial

Answer 4

the two part scientific name of a species

Question 5

genus

Answer 5

first part of the name of species

Question 6

specific epithet

Answer 6

second part of name of species

Question 7

the taxonomic groups from broad to narrow are … (8)

Answer 7

1. domain
2. kingdom
3. phylum
4. class
5. order
6. family
7. genus
8. species

Question 8

taxon

Answer 8

a taxonomic unit at any level of hierarchy

Question 9

phylogenetic trees

Answer 9

systematists depict evolutionary relationships

Question 10

phylocode

Answer 10

which recognizes only groups that include a common ancestor and all its descendents

Question 11

a phylogenetic tree represents …

Answer 11

a hypothesis about evolutionary relationships

Question 12

branch point

Answer 12

represents the divergence of two species

Question 13

sister taxa

Answer 13

groups that share an immediate common ancestor

Question 14

rooted tree

Answer 14

includes a branch to represent the last common ancestor of all taxa in the tree

Question 15

basal taxon

Answer 15

diverges early in the history of a group and originates near the common ancestor of the group

Question 16

polytomy

Answer 16

a branch from which more than two groups emerge

Question 17

phylogenetic trees show patterns of ____

Answer 17

descent, not phenotypic similarity

Question 18

do phylogenetic trees indicate when species evolve or how much change occurred in a lineage?

Answer 18

no

Question 19

to infer phylogenies systematists gather _____, ______, and ____

Answer 19

1. information about morphologies
2. genes
3. biochemistry of living organisms

Question 20

phenotypic and genetic similarities due to shared ancestry are ____

Answer 20

homologies

Question 21

similarity due to convergent evolution

Answer 21

analogy

Question 22

similarity due to shared ancestry

Answer 22

homology

Question 23

convergent evolution

Answer 23

occurs when similar environmental pressures and natural selection produce similar (analogous) adaptations in organisms from different evolutionary lineage

Question 24

homoplasies

Answer 24

Analogous structures or molecular sequences that evolved independently are also called
homoplasies

Question 25

homology can be distinguished form analogy by....

Answer 25

comparing fossil evidence and the degree of complexity

Question 26

the more complex two similar structures are, the more likely it is that they are ______

Answer 26

homologous

Question 27

molecular systematics

Answer 27

uses DNA and other molecular data to determine evolutionary relationships

Question 28

cladistics

Answer 28

groups organisms by common descent

Question 29

clade

Answer 29

a group of species that include an ancestral species and all its descendants

Question 30

do all groupings of organisms qualify as clades?

Answer 30

no

Question 31

monophyletic

Answer 31

signifying that it consists of the ancestor species and all its descendants

Question 32

paraphyletic grouping

Answer 32

consists of an ancestral species and some, but not all, of the descendants

Question 33

polyphyletic grouping

Answer 33

consists of various species with different ancestors

Question 34

in comparison with its ancestor, an organism has both ____ and ______

Answer 34

shared and different characteristics

Question 35

shared ancestral character

Answer 35

a character that originated in an ancestor of the taxo

Question 36

shared derived character

Answer 36

an evolutionary novelty unique to a particular clade

Question 37

outgroup

Answer 37

a species or group of species that is closely related to the ingroup, the various species being studied -outgroup is a group that has diverged before the ingroup

Question 38

ingroup

Answer 38

the various species being studied

Question 39

characteristics shared by the outgroup and ingroup are ....

Answer 39

ancestral characters that predate the divergence of both groups from a common ancestor

Question 40

maximum parsimony

Answer 40

assumes that the tree that requires the fewest evolutionary events (appearances of shared derived characters) is the most likely

Question 41

maximum likelihood

Answer 41

states that, given certain rules about how DNA changes over time, a tree can be found that reflects the most likely sequence of evolutionary events

Question 42

gene duplications increases the number of genes in the genome, providing....

Answer 42

more opportunities for evolutionary changes

Question 43

repeated gene duplications result in

Answer 43

gene families

Question 44

like homologous genes, duplicated genes can be traced to ....

Answer 44

common ancestor

Question 45

orthologous genes

Answer 45

found in a single copy in the genome and are homologous between species -they can diverge only after speciation occurs

Question 46

paralogous genes

Answer 46

result from gene duplication, so are found in more than one copy in the genome -they can diverge within the clade that carries them and often evolve new functions

Question 47

_____ genes are widespread and extend across many widely varied species

Answer 47

orthologous

Question 48

molecular clock

Answer 48

uses constant rates of evolution in some genes to estimate the absolute time of evolutionary change

Question 49

natural theary

Answer 49

states that much evolutionary change in genes and proteins has no effect on fitness and is not influenced by natural selection • It states that the rate of molecular change in these genes and proteins should be regular like a clock

Question 50

horizontal gene transfer

Answer 50

the movement of genes from one genome to another - occurs by exchange of transposable elements and plasmids, viral infection, and fusion of organisms - complicates efforts to build a tree of life