Intro to Environmental Science Exam 2

What is natural selection

the process whereby individual suited to a particular environment pass on more of their traits to the next generation

what is a mutation

changes in DNA coding sequence that occurs by chance

what is an example of a mutation

mistakes in DNA, toxins, radiation

what is an adaptation

acquisition of traits that allow a species to survive in its environment

who explained adaptations

charles darwin in natural selection

what is evolution

a trait must be inherited (genetics) for it to evolve

what are limiting factors

the single factor in the shortest supply relative to the demand

what are some examples of limiting factors

food supply, temperature, nesting sites

who proposed limiting factors

Von Liebig

what are tolerance limits

an environmental factor that has minimum and maximum beyond which a species cannot survive

what is a habitat

the place or set of environmental conditions in which a particular organism lives

what is an ecological niche

describes either the role played by species or the total set of environmental factors that affect its habitat; how it uses its habitat

what is a generalist niche

broad niche, eats anything

what is a specialist niche

narrow niche, eats one thing

how can ecological niches be described

by functional role (herbivore/ carnivore)

by habitat (polar/ temporal /tropical)

altitudinal zones are an example of:

ecological niches

temperatures rising is an example of:

tolerance zones

what is the competitive exclusion principle

no two species can occupy the same ecological niche at the same time; species that are more affected will be beat out

what is an example of the competitive exclusion principle

phragmites and cattails

what is resource partitioning

species co-exist in a habitat by utilizing different parts of a single resource

what is an example of resource partitioning

swallows eat bugs during day, bat eats them at night

what is speciation

the development of new species. this can happen due to geographic isolation

what is geographic isolation

a subpopulation becomes separated from main population

what is allopatric speciation

speciation by geographic isolation

what is sympatric speciation

organisms continue to live in the same place but becomes isolated by some other means

what is an example of sympatric speciation

some ferns doubles chromosomes and can’t breed with population and create new species

what is directional selection

one trait is being favored and the other being is eliminated so the population shifts toward one trait

what is stabilizing selection

the range of a trait is narrowed

what is disruptive selection

traits diverge toward the two extremes

what is taxonomy

the study of organisms and their relationships it traces now organisms have descended from common ancestor

what are the taxonomic categories

KPCOFGS

is this correct: Ulmus Americana

no, only genus capitalized

what is binomial

two names

what is intraspecific competition

competition among members of the same species

how can intraspecific competition be reduced

if young disperse

if animal defends a territory

is adults and juveniles occupy different niches.

what is interspecific competition

competition between members of different species

what is a predator

an organism that preys directly on another organism, whether or not this kills the prey

what is predator-mediated competition

what is mullerian mimicry

two harmful species evolve to look alike

what is batesian mimicry

harmless species mimic the warning coloration of harmful species to gain protection

what is symbiosis

two or more species live intimately together with their fates linked

what is mutualism and example

both organisms benefit from their association

fungus + algae = lichen

what is commensalism

one species benefits while the other neither benefits nor is harmed

what is parasitism and example

a form of predation is also sometimes considered a symbiosis because of the dependency of the parasite on the host

cowbirds lay eggs in other birds nest

what is a keystone species

plays a critical role in a biological community that is out of proportion to its abundance

what is primary productivity

rate of biomass production. used as an indication of the rate of solar energy conversion to chemical energy

what is net primary productivity

energy left after respiration

what is abundance

total number of organisms in a community

what is diversity

number of different species, ecological niches, or genetic variation

diversity ___ as abundance within a species ___ when moving from the equator to the poles

decreases

increases

what is ecological succession

an orderly sequence over time of species living on a site; one community of succeeded by another

what is primary succession and example

a community begins to develop on a site previously unoccupied by living organisms

a lava flow creates new land area that is colonized

what are pioneer species

the first colonists from primary succession

what is secondary succession and example

an existing community is disrupted and a new one subsequently develops at the site

chestnut blight

what is a climax community

community that develops last and remains the longest

what is an example of disturbance-adapted species

jack pine

what are the kingston plains

-forested region of northern michigan

-pine forest cut in 1890s

-primary succession from bare ground

-dominated by grassland vegetation in 1990s

-Dr. Barrett dissertation

what is a biome

areas sharing similar climate, topographic, and soil conditions, and thus the same basic types of biological communities

what is vertical zonation

vegetation zones determined by altitude

zones are horizontal ( change as you move vertically)

what is a tropical rainforest

humid regions in the tropics that support one of the most complex and biologically rich biomes

rainfall >200 cm/yr

what is a cloud forest

high in mountains where fog and mist keep vegetation continually moist

what is the soil like in tropical rainforest

thin , acidic, nutrient poor

what is a tropical seasonal forest

wet, dry seasons, hot temps always

soil is richer

deciduous plants

what is a savanna

a grassland with sparse tree cover

what is a desert and one veg ex

low moisture <30 cm/yr

joshua tree

what is a temperature grassland

few trees

herbaceous flowering plants

thick organic soils

much converted to farmland

what is a temperate shrubland (mediterranean)

warm, dry summers and cool moist winters

west sides of continents near sea

what is a chaparral and where are they found

temperate shrublands (california)

wildfires

what is a temperate deciduous forest

temperate regions that support lush summer plant growth when water is plentiful

what is a coniferous

has cones, evergreen, softwood

what is a needle leaf

has needles, evergreen, softwood

what is a broadleaf

wider and softer than needles, can be evergreen, hardwood

what is a deciduous

leaves fall and grow back, temperate regions

what is an american holly

broadleaves all winter fall in may

what is a boreal forest

northern coniferous forest

between 50 and 60 N

what are the zones of the boreal forest

50 and 60N

what is a taiga and where is it found

northernmost edge of boreal forest

extreme cold and short summer

what is a tundra

frozen most of the year

warm enough for plants but not tree

what is a benthic zone

ocean floor

what is the pelagic zone

water column above bottom

open ocean is a biological desert except areas where nutrients pushed by current

what is sargasso sea

seaweed, found in pelagic marine

what is the littoral zone

near shore

what are coastal zones

community vary in height, depth, temp, and nutrients

what are coral reefs

aggregations of coral polyps that live symbiotically w/ algae

their calcium skeletons build up the reef

what is coral bleaching

when corals expel their algal partners and die

what are mangroves

trees that grow in saltwater (muddy) along tropical coastlines

help stabilize shorelines

whata are estuaries

bays or semi-enclosed bodies of brackish water that form where rivers eneter the ocean

what is soil

a renewable resource that develops gradually through the weathering of rocks and the accumulation of organic material

what are the 4 components of soil

mineral, organic, water, air

what is the mineral component of soil

large and small pieces

what is the organic component of soil

living and decaying organisms

what is the water component of soil

liquid,bound and solid phases

what is soil texture

the amount of sand, silt, and clay in the soil

the most important characteristic or soils

what is loam

a soil thats considered the best for agriculture because they are a mix of sand, silt, and clay

what is mycorrhizal symbiosis

an association between plant roots and certain fungi

the plant feeds the fungus and the fungus provides water and inorganic nutrients to the plant enhancing growth

what is a soil horizon

horizontal layers of soils

what is the soil profile

O

A

E

B

C

parent

what is the O horizon

organic layer: leaf litter, most soil organisms and partially decomposed organisms

what is the A horizon

topsoil: mineral particles mixed with organic material

what is the E horizon

washed out: depleted of soluble nutrients