week 3 (ch 28 & 29)

Question 1

the most ancestral branch in the tree

Answer 1

root

Question 2

a node that depicts an ancestral branch dividing into three or more descendent branches

Answer 2

polytomy

Question 3

a taxon that diverged prior to the taxa that are the focus if the study; helps root the tree

Answer 3

out group

Question 4

any genetic morphological, physiological, or behavioral characteristic to be studied

Answer 4

character

Question 5

a characteristic that existed in an ancestor

Answer 5

ancestral trait

Question 6

a modified form of the ancestral trait found in a descendant

Answer 6

derived trait

Question 7

way of inferring a phylogenetic tree by identifying shared derived characteristics

Answer 7

classification approach

Question 8

a trait found in two or more taxa that is present in their most recent common ancestor but is missing in more distant ancestors

Answer 8

synapomorphy

Question 9

— allow biologists to recognize monophyletic groups

Answer 9

synapomorphy

Question 10

similarity in organisms due to common ancestry

Answer 10

homology

Question 11

similarity in organisms due to reasons other than common ancestry

Answer 11

homoplasy

Question 12

an unnatural group that does not include the most common ancestor

Answer 12

polyphyletic group

Question 13

a group that includes an ancestral population and some of its descendants, but not all.

Answer 13

paraphyletic group

Question 14

a common cause of homoplasy

Answer 14

convergent evolution

Question 15

occurs when natural selection favors similar solutions to problems

Answer 15

convergent evolution

Question 16

a piece of physical evidence from an organism that lived in the past

Answer 16

fossil

Question 17

the total collection of fossils that have been found throughout the world

Answer 17

fossil record

Question 18

the different biases of fossil records

Answer 18

habitat bias
taxonomic and tissue bias
temporal bias
abundance bias

Question 19

organisms that love in areas where sediments are actively being deposited– including beaches, mudflats, and swamps– are much more likely to from fossils than are organisms that live in other places

Answer 19

habitat bias

Question 20

organisms with hard parts such as vibes or shells are more likely to leave fossil evidence

Answer 20

taxonomical and tissue bias

Question 21

recent fossils are much more common than ancient fossils

Answer 21

temporal bias

Question 22

organisms that there are a lot of, widespread, and/ or present on earth for long periods of time leave evidence much more often

Answer 22

abundance bias

Question 23

between the formation if earth and the appearance of most animal groups

Answer 23

Precambrian

Question 24

2 key things about the Precambrian

Answer 24

• life was unicellular

- almost no oxygen

Question 25

eon that comes after the Precambrian

Answer 25

Phanerozoic eon

Question 26

eras within the Phanerozoic eon

Answer 26

1. Paleozoic 2. Mesozoic 3. Cenozoic

Question 27

era tag includes the origin and initial diversification of animals, plants, and fungi-- and the appearance of LAND ANIMALS

Answer 27

Paleozoic

Question 28

when a single lineage rapidly produces MANY descendant species with a wide range of adaptive live forms ---- has occurred

Answer 28

adaptive radiation

Question 29

what are two mechanisms that can trigger adaptive radiation?

Answer 29

new resources (ecological opportunity) and new ways to exploit these resources ( morphological innovation) eg. Hawaiian silverswords subsets look different because they grow in different niches

Question 30

an example of morphological innovation

Answer 30

feathers originally evolved for insulation but where then used for flight

Question 31

time in which much adaptive radiation occurred

Answer 31

Cambrian explosion

Question 32

what triggered the Cambrian explosion?

Answer 32

- higher oxygen levels - evolution of predation - new niches beget more new niches - new genes, new bodies

Question 33

the rapid extinction of a large number of lineages scattered throughout a tree of life ( cut off = 60%)

Answer 33

mass extinction

Question 34

the lower, average rate of extinction when a mass extinction is not occurring

Answer 34

background extinction

Question 35

extinction that killed 90% of species ( including dinosaurs!)

Answer 35

end- Permian extinction

Question 36

impact hypothesis

Answer 36

end- Permian extinction was caused when an astride stuck earth

Question 37

endpoint of a branch; represents a living or extinct group of genes, species, families, phyla, or other taxa

Answer 37

tip/ terminal node

Question 38

archaea are... and have...

Answer 38

prokaryotic! | - pho lollipops in their plasma membrane that are made of isoprene

Question 39

bacteria that cause disease

Answer 39

pathogenic

Question 40

Koch's postulates

Answer 40

1. microbe must be present in the individual suffering 2. organism must be grown away from the host organism 3. when you inject it back into a heathy person, symptoms should appear 4. organism should be again isolated and grown (does it look the same?)

Question 41

germ theory of disease introduced the idea that...

Answer 41

bacteria and viruses can be passed from person to person and cause disease

Question 42

virulence

Answer 42

ability to cause disease

Question 43

extracting DNA and sequencing from a sample and then identifying species and biochemical pathways by comparing the DNA sequences of those with known genes

Answer 43

meta genomics/ environmental sequencing

Question 44

sequencing a specific gene from organisms found in a particular habitat

Answer 44

direct sequencing

Question 45

use energy on light to excite electrons

Answer 45

phototrophs

Question 46

oxidize things like sure for food

Answer 46

chemooganotrophs

Question 47

oxidize inorganic material like NH3 for food

Answer 47

chemolithitrophs

Question 48

self feeders

Answer 48

autotrophs

Question 49

other feeders

Answer 49

heterotrophs

Question 50

species that use water as a source of electrons for photosynthesis

Answer 50

oxygenic

Question 51

species that use a molecule other than water as the source of electrons

Answer 51

anoxygenic

Question 52

turning atmospheric N2 into -NH2

Answer 52

nitrogen fixation

Question 53

a lineage of photosynthetic bacteria; the first to do oxygen producing photosynthesis

Answer 53

Cyanobacteria

Question 54

respiration without oxygen

Answer 54

aerobic respiration

Question 55

how were Cyanobacteria responsible for a substantial change in the earth's atmosphere

Answer 55

they increased the oxygen level

Question 56

what would happen if bacteria and arches did not exist?

Answer 56

there would be sooo much less oxygen, and much more N2 in the atmosphere

Question 57

Firmicutes

Answer 57

- have gram positive cell walls | - some of the species within this group produce yogurt and cheese!!

Question 58

Cyanobacteria

Answer 58

- dominate marine environments | - preform oxygenic photosynthesis

Question 59

actinobacteria

Answer 59

- G and C represent over 75% of their base pairs

Question 60

spirochaetes

Answer 60

- are bacteria | - have spirochete flagellum that allow them to swim

Question 61

chlamydiae

Answer 61

- are bacteria | - endosymbionts ( live as parasites inside host cells)

Question 62

thaumaecgaeota

Answer 62

ammonia oxidizers ( use ammonia as a source of electrons and generate nitrite as a byproduct)

Question 63

euryarchaeota

Answer 63

-archaea that are methanogens ( create CH4 as a byproduct of respiration)