Exam 1 Flashcards
1
Q
General definition of Biodiversity
A
variation at all levels of biological organization
2
Q
Types of biodiversity
A
Genetic Diversity
Organismal Diversity
Ecological Diversity
3
Q
Genetic Diversity
A
variation in the genetic make-up between individuals within a population and between populations
4
Q
Organismal Diversity
A
the variation in a particular level of the taxonomic hierarchy (species, genera, and beyond)
5
Q
species richness:
A
the number of species within a given sampling area
6
Q
Species Evenness
A
how abundant each species is relative to the total number of individuals
7
Q
Ecological (ecosystem) Diversity
A
ecological differences between habitats and biomes
8
Q
Spatial Patterns of Diversity
A
Alpha diversity
Beta Diversity
Gamma Diversity
Species-Area Relationships
9
Q
Alpha Diversity
A
diversity within a particular area or ecosystem
10
Q
Beta Diversity
A
differences in alpha diversity between ecosystems
11
Q
Gamma Diversity
A
overall diversity for the different ecosystems in a broad region
12
Q
How many extant species are described
A
~1.5 million described
13
Q
How many estimated extant species are there
A
.5 million - 1 trillion
14
Q
Out of all the diversity, how many are Vertebrate? Viruses? Fungi? Protists? Plants? Invertebrate?
A
3% (vertebrate)
15
Q
How old is the Earth?
A
4.5 billion years
16
Q
Archaen Eon
A
- Low oxygen environment
- First life arises
- cyanobacteria begin photosynthesizing
17
Q
How many years ago did life arise and in what era
A
3.8 Billion, Archaen
18
Q
Proterozoic Eon
A
- Great oxygenation even
- Eukaryotes evolve
- Life dominated by small, small-bodied eukaryotes
19
Q
Cryogenian Period
A
- “Snowball Earth”
- Massive ice ages
- Possibly leads to more diversity in Ediacaran
20
Q
Ediacaran Period
A
-Proliferation of multicellular, soft-bodied organisms
21
Q
Paleozoic Era
A
- Nearly all invertebrate phyla appear
- Life begins in oceans and moves to land
22
Q
Cambrian Period
A
- Cambrian Explosion
- Most major animal phyla appear
- marine life still dominant
- origin of general body plan for metazoans
23
Q
Cambrian Explosion
A
major diversification of form and function
24
Q
Ordovician Period
A
- first vertebrates with true bones appear
- first life on land
- mass extinction at the end
25
Silurian Period
- life on land progresses
- first appearance of vascular plants
- major diversification of fish
26
Devonian Period
- significant radiation of life on land
- tetrapods and anthropoids colonize land
- mass extinction near end of period
27
Carboniferous Period
- warm and humid
- Extensive forests generate massive coal reserves
- reptiles appear
28
Permian period
- supercontinent pangea
| - starts with ice age and ends with mass extinction event
29
Mesozoic Era
- "Age of the Dinosaurs"
| - fragmentation of Pangea leads to much specification
30
Triassic Period
- warm and dry climate
- slow recovery from Permian extinction
- mammals and dinosaurs evolve
31
Jurassic Periods
- first birds appear
- largest land animals of all time present
- cycads dominate plant world
32
Cretaceous Period
- Sea levels reach highest point
- angiosperms (flowering plants) appear
- age of reptiles
- ends with mass extinction
33
Cenozoic Era
-mammals dominant on land
34
Pleistocene Epoch
last major ice age
35
Holocene Epoch
after ice age, allows for species radiation
36
What Epoch are we said to be in?
Anthropocene
37
Mass Extinction Events
- short events resulting in massive species loss
- random
- open up niches for adaptive radiation and greater diversity
38
What was the largest mass extinction event
```
Permian Extinction (95% of all species lost)
-prob due to gradual environmental changes and a catastrophic event
```
39
What was the dinosaur extinction
Cretaceous-Tertiary (75%)
40
Human-caused mass extinction event
Holocene or Anthropocene
41
Fossil record shoes a______
erratic but relentless increase in biological diversity
42
Natural selection (is/is not) the only driver of species turnover and evolutionary change
IS NOT
43
Why are viruses said to be alive
- Posses genes and evolve by natural selection
| - Replicate by generation multiple copies of their genetic makeup
44
Why are viruses said NOT to be alive
- No oxygen exchange
- lack finite lifespan
- do not require nutrition to survive or replicate
45
Biological Species
population of morphologically similar, interfertile organisms that are reproductively isolated from other such groups
46
Viral Species
a polythetic class of viruses that constitute a replicating lineage and occupy a particular niche.
47
UNCOATING
The viral protein coat is removed to expose the viral NA to the cytoplasm of the cell
48
Transcription
Naked viral NA acts as template for production of viral mRNA, or is the mRNA itself
49
Translation
Viral mRNA is translated by host ribosomes and tRNAs into viral proteins.
50
Replication
Parental viral NA is copied for progeny virions. Process catalyzed by the viral replicase enzyme.
51
Assembly
Viral coat protein and NA assemble to form complete virions.
52
Release
The progeny virions are released from the cell to infect other cells and other susceptible individuals
53
Cytocidal infections
cell death as end result of infection
54
Noncytocidal infections
Acute or persistent
55
Acute infections
viruses flushed out of body quickly by various defense mechanisms
56
Chronic infections
the infected cells continually produce irons
57
Latent infections
the infected cells do not continually produce irons. Virus becomes dormant for a time before becoming active again
58
Persistent infections often are _________
lysogenic
59
Neodarwinism
blending of Darwinism & Mendelism. Evolution arises exclusively from gradual accumulation of mutations & sex recombo of genes under control of natural selection
60
Symbiogenesis
life forms join genomes honed by evolution, & such fusions often lead to major saltations. This mechanism is not random, but a creative force.
61
How many viral elements constitute the human genome
50%
62
up to _____ of some plant genomes is viral
90%
63
What constitutes the virus growth cycle
```
Uncoating
Transcription
Translation
Replication
Assembly
Release
```
64
Taxonomy
the science of naming, describing, and classifying living things; one aspect of systematics
65
Taxon
a group of organisms at a particular level of a classification system
66
Who were the first to organize like organisms in GENERA
Greeks and Romans
67
Who developed binomial system
Carolus Linnaeus
68
Polynomial system
began in the middle ages
| a series of descriptive terms added to the name of a genus to refer to a particular order
69
Character
any recognizable trait, feature, or property of an organism (eye color, leaf shape)
70
Character state
a discrete condition within a character
71
Holotype
organism on which species description is based
72
Isotope
collected at same place and time as holotype
73
Paratype
collected at different place or time than holotype
74
Systematics
the study of the diversity of organisms and their evolutionary relationships
75
Phylogeny
the evolutionary history of a taxon
76
Phylogenic trees
show inferred evolutionary relationships hypothesized by particular investigators
77
Cladogram
a simplified visualization of a taxon evolutionary history
78
character states are used to
group related organisms
79
Monophyletic group
includes the most recent common ancestor and all of its descendants (clade)
80
Paraphyletic group
includes the most recent common ancestor but not all of its descendants
81
Polyphyletic group
grouping derived from more than one ancestor
82
outgroup
a taxon that serves as a reference group for other taxa in a cladogram
83
In situ conservation
- establish protected areas
- promote sustainable development
- restore degraded ecosystems
- control invasive species
84
Ex situ conservation
- seed banks and zoos
- culture collections
- captive breeding
85
Trends in biodiversity
- increases with area
- increases from poles to equator
- decreases with elevation
86
Endemic Species
species found only in a single, limited area
87
Trends in endemism
- peaks on large
| - increases from poles to equator
88
there are ____ hotspot regions
25
89
Criteria for hotspots
- at least 1500 species of endemic vascular plants
- lost at least 70% of its original habitat
- (irreplaceable and threatened)
90
Biodiversity hotspots cover _____ of Earth's land surface, constitute ____ of all extant plant species, and ______ of all extant vertebrates
1.4%
45%
35%
