unit 2

Question 1

Ecosystem diversity

Answer 1

the number of diff. habitats available in a given area

Question 2

Species diversity

Answer 2

the number of diff. species in an ecosystem and the balance or evenness of the pop. sizes of all species in the ecosystem

Question 3

Genetic diversity

Answer 3

how different the genes are of individuals within a population (group of the same species)

Question 4

Evenness

Answer 4

measure of how all of the individual organisms in an ecosystem are balanced between the different species

Question 5

Richness

Answer 5

total number of different species found in an ecosystem

Question 6

Genetic diversity

Answer 6

measure of how different the genomes (set of genes) are of the individuals within a population of a given species

Question 7

Bottleneck events

Answer 7

natural disaster/human hab. destruction) that drastically reduces pop. size & kills organisms regardless of their genome

Question 8

Inbreeding

Answer 8

when organisms mate with closely related “family” members, Leads to higher chance of offspring having harmful genetic mutations because they’re getting similar genotypes from both parents

Question 9

Resilience

Answer 9

the ability of an ecosystem to return to its original conditions after a major disturbance (wind storm, fire, flood, clear-cutting, etc.)

Question 9

Higher species diversity =

Answer 9

higher ecosystem resilience

Question 10

Provisioning

Answer 10

Goods taken directly from ecosystems or made from nat. resources (wood, paper, food)

Question 10

Regulating

Answer 10

Nat. ecosystems regulate climate/air quality, reducing storm damage & healthcare costs

Question 11

Supporting

Answer 11

Nat. ecosystems support processes we do ourselves, making them cheaper & easier(bees pollinate crops)

Question 12

Islands closer to the “mainland”

Answer 12

support more species

Question 13

Cultural

Answer 13

Money generate by recreation (parks, camping, tours) or scientific knowledge

Question 14

Human activities ….

Answer 14

disrupt the ability of ecosystems to function, which decreases the value of ecosystem services they provide

Question 15

Overfishing leads to

Answer 15

fish pop. collapse (lost fishing jobs and lower fish sales in the future)

Question 15

Clearing land for ag./cities removes trees that store CO2 (more CO2 in atm.=

Answer 15

more CC = more storm damage & crop failure)

Question 16

Zone of physiological stress

Answer 16

range where organisms survive, but experience some stress such as infertility, lack of growth, decreased activity, etc.

Question 16

Larger Islands support ..

Answer 16

more total species

Question 17

Zone of intolerance:

Answer 17

range where the organism will die

Ex: thermal shock, suffocation, lack of food/water/oxygen

Question 17

Natural Disturbances

Answer 17

natural event that disrupts the structure and or function of an ecosystem
Ex: Tornados, hurricanes, asteroids, forest fires, drought

Question 18

Episodic

Answer 18

occasional events with irregular frequency (ex: hurricanes, droughts, fires)

Question 19

Ecological Range of Tolerance

Answer 19

Range of conditions such as temperature, salinity, pH, or sunlight that an organism can endure before injury or death

Question 19

Optimal range:

Answer 19

range where organisms survive, grow, and reproduce

Question 20

Periodic

Answer 20

occurs with regular frequency (ex: dry-wet seasons)

Question 21

Random:

Answer 21

no regular frequency (volcanoes, earthquakes, and asteroids)

Question 22

Natural Climate Change

Answer 22

Earth’s climate has varied over geologic time for numerous reasons Ex: Slight changes in earth’s orbit & tilt cause mini ice ages & warmer periods as earth shifts slightly closer to & further from sun

Question 23

Also due to climate change,

Answer 23

Sea level has varied over geological time as glacial ice on earth melts & forms

Question 24

Migration

Answer 24

Wildlife may migrate to a new habitat as the result of natural disruptions Ex: wildebeests migrating to follow rain patterns of African savanna

Question 25

Adaptation

Answer 25

a new trait that increases an organism’s fitness (ability to survive and reproduce)

Question 26

Genetic diversity exists because:

Answer 26

Random mutations while DNA is being copied create new traits Crossing over in parent chromosomes creates new combinations of genes (and therefore traits)

Question 27

Natural selection

Answer 27

organisms that are better adapted to their env. survive and reproduce more offspring

Question 28

Evolution

Answer 28

Individuals with adaptations pass them on to offspring & individuals without adaptations die off, which leads to the entire population having the adaptation over time

Question 29

Selective pressure/force:

Answer 29

the environmental condition that kills individuals without the adaptation

Question 30

Environmental Change & Evolution

Answer 30

The environment an organism lives in determines which traits are adaptations As environments change, different traits may become adaptations & old traits may become disadvantages

Question 31

Pace of Evolution

Answer 31

The more rapidly an env. changes, the less likely a species in the env. will be to adapt to those changes If the pace of env. change is too rapid, many species may migrate out of the env. or die-off completely

Question 32

Ecological Succession

Answer 32

A series of predictable stages of growth that a forest goes through

Question 33

Primary Succession

Answer 33

Starts from bare rock in an area with no previous soil formation Moss & lichen spores carried by the wind grow directly on rocks, breaking them down to form soil

Question 34

Secondary Succession:

Answer 34

starts from already established soil, in an area where a disturbance (fire/tornado/human land clearing) cleared out the majority of plant life Grasses, sedges, wildflowers, and berry bushes have seeds dispersed by wind or animal droppings

Question 35

Stages of Succession

Answer 35

Stages are characterized by which types of plant species dominate the ecosystem; different species are adapted to the conditions of the different stages

Question 36

Pioneer or early succession species

Answer 36

appear first, when the ground is simply bare rock, or bare soil after a disturbance

Question 37

Characteristics of Pioneer or early succession species

Answer 37

seeds spread by wind or animals, fast growing, tolerant of shallow soil and full sunlight moss, lichen (bare rock) | wildflowers, raspberries, grasses/sedges

Question 38

Mid-successional species

Answer 38

appear after pioneer species have helped develop deeper soil with more nutrients by their cycles of growth/death

Question 39

Late successional or climax community species

Answer 39

appear last, after soil is deepened and enriched with nutrients by cycles of growth and death by early & mid successional species

Question 40

Characteristics of Mid-successional species

Answer 40

relatively fast growing, larger plants that need deeper soils with more nutrients than pioneers, sun tolerant shrubs, bushes, fast-growing trees like aspen, cherry, and pine

Question 41

Characteristics of Late successional or climax community species

Answer 41

large, slow-growing trees that are tolerant of shade and require deep soils for large root networks Ex: maples, oaks, other large trees