Ch. 25, 26, 27 Flashcards Preview

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Flashcards in Ch. 25, 26, 27 Deck (119):
1

The scientific discipline concerned with classifying and naming organisms

Taxonomy

2

What are the taxonomic groups from broad to narrow?

Domain, kingdom, phylum, class, order family genus, species

3

Similarity due to shared ancestry

Homology

4

Similarity due to convergent evolution

Analogy

5

When similar environmental pressures and natural selection produce similar adaptations in organisms from different evolutionary lineages

Convergent evolution

6

Analogous structures or molecular sequences that evolved independently

Homoplasies

7

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

Paraphyletic grouping

8

Grouping that includes distantly related species but does not include their most recent common ancestor

Apolyphyletic grouping

9

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

Molecular clock

10

Genes found in a single copy in the genome. Are homologous between species.

Orthologous genes

11

The movement of genes from one genome to another

Horizontal gene transfer

12

When did earth form

4.6 billion years ago

13

What was the first genetic material?

RNA

14

What kind of species is the fossil record biased in favor of?

Species that existed for a long time, were abundant and widespread, and had hard parts

15

How are the absolute ages of fossils determined?

By radiometric dating

16

What are the three eras that the Phanerozoic era is divided into?

Paleozoic, Mesozoic, Cenozoic

17

What is the name of the oldest known fossils?

Stromatolites

18

Rocks formed by the accumulation of sedimentary layers on bacterial mats

Stromatolites

19

Theory that proposes that mitochondria and plastids (chloroplasts & related organelles) were formerly small prokaryotes living within larger host cells

The endosymbiont theory

20

What causes extinction?

Changes in a species' environment

21

The result of disruptive global environmental changes

Mass extinctions

22

The sudden appearance of fossils resembling modern animal phyla in the Cambrian period

Cambrian explosion

23

When was the Cambrian period?

535 million years ago

24

What are some effects that formation of Pangaea had?

Deepening of ocean basins, reduction in the shallow water habitat, a colder and drier climate inland

25

When was Pangaea formed?

250 million years ago

26

What is the most important feature of all prokaryotic cells? Why?

Their cell wall. It maintains cell shape, protects the cell, and prevents it from bursting in a hypotonic environment

27

Bacteria cell walls contain ____, a network of sugar polymers cross-linked by polypeptides

Peptidoglycan

28

Allow prokaryotes to exchange DNA

Pili

29

Metabolic cooperation occurs between different prokaryotic species in surface-coating colonies

Biofilms

30

What are the four major modes of nutrition that energy and carbon sources combine to give?

Photoautotrophy, chemoautotrophy, photoheterotrophy, chemoheterotrophy

31

Name three factors that contribute to genetic diversity in prokaryotes

Rapid reproduction, mutation, genetic recombination

32

The movement of genes between bacteria by bacteriophages (viruses that infect bacteria)

Transduction

33

How can some bacteria survive antibiotics?

Some bacteria have R plasmids which carry genes for antibiotic resistance

34

Obtain energy from light

Phototrophs

35

Obtain energy from chemicals

Chemotrophs

36

Require CO2 as a carbon source

Autotrophs

37

Require an organic nutrient (like carbon) to make organic compounds

Heterotrophs

38

What are three things that prokaryotes can sometimes increase for plant growth?

The availability of nitrogen, phosphorus, and potassium

39

What are three factors contributing to extinction?

Toxic conditions, global warming, intense volcanos

40

How are RNA molecules produced?

Spontaneously from simple molecules

41

Time required for half the parent to decay

Half-life

42

How long ago was Earth formed?

4.6 billion years ago

43

Rapid evolution of diversely adapted species from a common ancestor

Adaptive radiation

44

Groups that share an immediate common ancestor

Sister taxa

45

What is the purpose of cladistics?

To group organisms by common descent

46

Character that originated in an ancestor of the taxon

Shared ancestral character

47

Evolutionary novelty unique to a particular clade

Shared derived character

48

What was the first cell?

Prokaryote

49

Are prokaryotes multicellular or unicellular?

Unicellular

50

What makes up the cell walls of eukaryotes?

Cellulose or chitin

51

What are the three main parts that bacterial flagella are composed of?

Motor, hook, and filament

52

What are three key functions of prokaryotic reproduction?

1. Small
2. Reproduce by binary fusion
3. Short generation time

53

What are three factors that contribute to genetic diversity?

1. Rapid reproduction
2. Mutation
3. Genetic recombination

54

What covers many prokaryotes?

Capsule

55

What is the purpose of R plasmids?

Carry genes for antibiotic resistance

56

One bacterial cell attaches a pilus to the other bacterial cell in order to transfer DNA

//when genetic material is being transferred between prokaryotic cells

Conjugation

57

What are the two parts in the binomial format in naming an organism?

Genus and epithet

58

Group that consists of an ancestral species and all of its descendants

Monophyletic group

59

What does branch length represent on a phylogenetic tree?

Level of evolutionary change or times which particular events occurred

60

What are the two types of homologous genes?

Orthologous and paralogous

61

What are the three domains of life?

Eukarya, archaea, bacteria

62

A group which includes an ancestral species and all of its descendants

Clade

63

Consists of distantly related species but does not include the most recent common ancestor

Polyphyletic group

64

Where lineages diverge on a phylogenetic tree

Branch point

65

Bacteria that have a large amount of peptidoglycan on the cell wall

Gram positive bacteria

66

Bacteria that have less peptidoglycan. Have an outer membrane that contains lipopolysaccharides

Gram negative bacteria

67

What is a way that mutualistic bacteria benefits humans?

Digests food we cannot break down; signals for building of network of intestinal blood vessels; induce human cells to produce antimicrobial compounds

68

Released when the bacteria dies and the cell wall breaks down

Endotoxins

69

Proteins released by bacteria that causes illness and disease in humans

Exotoxins

70

One species benefits but the other is neither harmed nor gains any benefit in the relationship

Commensalism

71

Is cyanobacteria gram positive or gram negative?

Gram negative

72

What is the energy source of photo heterotrophs?

Light

73

A time scale dividing Earth's history into four eons and several other subdivisions

Geologic record

74

In which eon did single celled eukaryotes appear on earth?

Proterozoic eon

75

What caused the single continent Pangea to become the 7 continents of present day?

Continental drift

76

What were the two most recognized of the "Big Five" mass extinction events?

Permian and Cretaceous

77

Deep sea vents that release warm, high pH water

Alkaline vents

78

What are the four stages that had to happen for very simple cells to be produced in early earth?

1. Abiotic synthesis of small organic molecules
2. Joining these small molecules to make macromolecules
3. Packaging molecules into protocells
4. Origin of self-replicating molecules (making inheritance possible)

79

RNA catalysts that can also aid in duplicating RNA

Ribozymes

80

True or false: in water lipids and other organic molecules can spontaneously form vesicles with a lipid bilayer

True

81

What group of animals do mammals belong to?

Tetrapods

82

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

Maximum parsimony

83

The ability to move toward or away from a stimulus

Taxis

84

In a heterogeneous environment, many bacteria exhibit ___

Taxis

85

Some species of bacteria have smaller rings of DNA called ___

Plasmids

86

Movement of genes among individuals from different species

Horizontal gene transfer

87

Some archaea live in extreme environments and are called ___

Extremophiles

88

Live in highly saline environments

Extreme halophiles

89

Thrive in hot environments

Extreme thermophiles

90

An ecological relationship in which two species live in close contact: a larger host and a smaller symbiont

Symbiosis

91

One organism benefits while neither harming or helping the other

Commensalism

92

Both symbiotic organisms benefit

Mutualism

93

The emergence of terrestrial vertebrates, the impact of mass extinctions, and the origin of flight in birds are examples of what kind of changes?

Macroevolutionary changes

94

The evolutionary history of a species or group of related species

Phylogeny

95

What do small organic molecules do when they are concentrated on hot sand, clay or rock?

They polymerize

96

What are two key properties of life that may have appeared together in protocells?

Replication and metabolism

97

How may have protocells formed?

From fluid-filled vesicles with a membrane-like structure

98

What do ribosomes do?

Catalyze reactions and can make complementary copies of short stretches of RNA

99

T or F: natural selection has produced self-replicating RNA molecules

True

100

Give an example of phylogeny

Shows that legless lizards and snakes evolved from different lineages of legged lizards

101

Classifies organisms and determines their evolutionary relationships

Systematics

102

The two-part scientific name of a species

Binomial

103

List five parts of a phylogenetic tree

1. Branch point
2. Sister taxa
3. Rooted tree
4. Basal taxon
5. Polytomy

104

Represents divergence of two species

Branch point

105

Groups that share immediate common ancestor

Sister taxa

106

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

Rooted tree

107

Diverges early in history of a group; originates near common ancestor of group

Basal taxon

108

Branch from which more than two groups emerge

Polytomy

109

What can phylogenetic trees not show?

When species evolved or how much change occurred in a lineage

110

Give example of practical use of phylogeny

To identify the species of whale from which whale meat originated

111

What makes Utah's Great Salt Lake a pink color?

Living prokaryotes

112

What is the salt concentration that Utah's Great Salt Lake can reach?

32%

113

True or false: prokaryotes can only survive in certain conditions

False: prokaryotes can thrive almost anywhere, even in places that are too acidic, salty, cold, or hot for most other organisms

114

What are the two domains that prokaryotes are divided into?

Bacteria and archaea

115

What are the three most common shapes of prokaryotes?

Spheres (cocci), rods (bacilli), and spirals

116

What do bacterial cell walls contain?

Peptidoglycan-a network of sugar polymers cross-linked by polypeptides

117

Archaea contain ___ and ____ but lack ____

Polysaccharides and proteins; lack peptidoglycan

118

Simpler walls, lots of peptidoglycan

Gram-positive

119

Less peptidoglycan; outer membrane can be toxic

Gram-negative