Exam 2

Mutualism

(+,+) Both species benefit because both are able to secure resources better living together than separate

Predation

(+,-) Organisms hunt, kill, and consume prey Predators have adaptations to help them hunt (sharp teeth/strong jaw)

Parasitism

(+,-) Organisms live and feed in/on other organisms Typically does not kill hosts, but does harm

Commensalism

(+,0) One species benefits, the other is unaffected Ball moss & tree Cattle egret & cow Whale & barnacle Remoras & shark

Competition

(-,-) Interaction among organisms vying for the same limited resource in an ecosystem

Growth Rate

(births/1,000 individuals) - (deaths/1,000 individuals)

k-adapted species

- long life - slower growth - mature later - few, large offspring - high parental care/protection - adaptes to stable environment - predators - niche specialists

Nitrogen Cycle

1. Nitrogen fixing bacteria are needed to convert N2 to NH3, a form of nitrogen that can be used by many producers. 2. Microbes are needed to decompose organic matter, releasing NH4 as a waste product. 3. Bacteria are needed for nitrification to convert NH4 to NO3. 4. Denitrifying bacteria are needed to convert NO3 back to atmospheric nitrogen (N2).

Temperate Zone

25° to 60 ° N and S Annual precipitation 200 mm - > 2,000 mm Annual temperature 5 - 20° C Growing seasons 4-10 months Reliable rainfall year-round Most of the trees in this biome survive the cold winter by losing their leaves. Precipitation - 75-150 cm/yr Temperature: Hot summers and cold winters Topsoil is rich in organic material and underlain by clay Vegetation is primarily deciduous - Oak, maple, beech Animals: Deer, bear and small animals Most of this biome land area has been regenerated after farming & timber harvest

Mutualism

A butterfly finds nectar stored inside the flowers and eats it. In the process he gets pollen smeared on his body. When he is finished hunting for nectar, the butterfly flies to another flower of the same species to find more nectar. Some of the pollen gets scraped off onto the second flower.

Interspecific Competition

A giraffe and an elephant are both eating leaves from an acacia tree in the savanna. This is an example of:

Population

A group of individuals of the same species living and interacting in the same region

Solar Energy

A large amount, but not easily used by cells or not always available

Polar Zone

Above 60° N and S latitude Very cold, < 5° C Short growing seasons Limited abundance and diversity of life

Exponential Growth

Abundant growth factors produce ________

r-selected species

Adapt well to unpredictable environments High biotic potential (r) Can increase/decrease quickly in response to environmental changes Examples: Dandelions, deer mice, and spotted knapweed

Open-Pit Mining

Adds phosphorous and nitrogen to the hydrosphere, where they can alter plant growth and pollute aquatic ecosystems Same as animal waste and fertilizing

Density Independent Factors

Affect a population regardless of its size, and can decrease the population Storms, fires, floods, avalanches

Matter Cycles

All ecosystems function through two fundamental processes: __________ and energy flow

Energy Flow

All ecosystems function through two fundamental processes: matter cycles and __________

Population

All individuals of a species which live in the same geographic area and interbreed Fluctuate in size and have varied distributions

Community

All the different populations that live together in an area Plants, animals, and other species

Assimilation

Ammonium (NH4+ ) taken up by plants and consumed by animals to make biological molecules

Nitrogen Fixation

Bacteria converts atmospheric nitrogen into ammonium (N2) to (NH4+ )

Carbon Cycle

Balanced between respiration and photosynthesis

Interspecific

Between individuals in 2 different species

Intraspecific

Between individuals of the same species in a population

Grassland

Biome with the most nutrient-rich soil

Climatic Factors

Biomes are defined as distinctive types of ecosystems determined by:

Terrestrial Biomes

Biomes on land (forests, taiga, tundra, etc.) 10 major biomes plus mountainous regions are distributed across Earth's land masses

r-selected species

Can have sudden population growths which may overshoot carrying capacity and suddenly crash

Exponential Growth

Cannot last forever because growth rates decrease as a population fills its environment

Symbiosis

Close biological/ecological relationship between 2 species Mutualism Parasitism Commensalism

Grassland

Cold winters, hot summers Too dry for forests, too wet for deserts Precipitation 250 - 750 mm/yr. - too little to support trees Rich organic soil horizon Periodic fires keep grasses dominant, limit tree growth Grazing animals, small mammals, reptiles, birds of prey

Tundra

Cold winters; short summers Growing season < 3 months Precipitation 100-500 mm/yr

Boreal Forest

Cold, dry winters Growing season < 4 months Precipitation 500-1,500 mm/yr. Soils are acidic and mineral poor Vegetation comprised of drought resistant conifers: White spruce, Balsam fir, Eastern larch Mostly small animals and migrating birds Some large animals are present - Wolves, bear, moose

Species Interactions

Control population and maintain carrying capacity More Diversity = More Relationships

Nitrification

Converts ammonium into nitrates (NH4+ ) to (NO3-)

Denitrification

Converts nitrates back to atmospheric nitrogen gas (NO3-) to (N2)

Terrestrial Biome

Defined primarily by both temperature and precipitation

N-cycle

Depends on many types of soil bacteria Often limits nutrients for plants (I.e. burning fossil fuels, fertilizing, etc.)

Resource Partitioning

Division of resources so potential competitors may coexist

Consumers

Eat other organisms and take in their carbon

Primary Consumers

Eat producers on the trophic levels

Tertiary Consumers

Eat secondary consumers on the trophic levels Carnivores

Quaternary Consumers

Eat tertiary consumers on the trophic levels

Secondary Consumers

Eats primary consumers on the trophic levels Herbivores

Population Dynamics

Ecologists who study ___ ____ (changes in population size and makeup) find some population sizes change predictably while others fluctuate randomly.

Density-Dependent Factors

Effects increase as populations grow Disease, competition, predation

Mountain

Experience same biome transitions in altitude as continent does in latitude

Tropical Zone

Extends 25°N and S Average monthly temp > 20° C Annual precipitation varies

some

Fire is a natural element of terrestrial ecosystems in only ____ ecosystems

Predator Defense

Fleeing/Running Hard shell Quills (Porcupine) Living in groups Camouflage Chemical Defense (poison) Mimicry

Energy Flow

Flows from producers (TL1) to Quaternary Consumers (TL5) in a linear fashion

Food Webs

Food chains linked together to show connections in community More complex = Greater stability

Energy

Foundation of every ecosystem Captured through photosynthesis Passed from organism to organism through the food chain

7.2%

From 2009-2010, the Yellowstone wolf population increased from 320 to 343, a growth rate of:

Range

Geographic area where a species (or one of its populations) can be found Influenced by behavioral and ecological factors Reflects how individuals interact with each other and their environment.

Keystone Species

Impacts its community more than its mere abundance would predict

0.05

In 1920, the elk population was 10,000. In 1921 , it was 10,500. What was the population growth rate?

367

In 2010, the Yellowstone wolf population was 343, with a growth rate of 7%. We would predict that the population would be __________ in 2011 if the growth rate remains constant.

Assimilation

In the Nitrogen cycle, which step does not involve bacteria?

Clumped Distribution

In which population distribution pattern would individuals within the population experience the most competition with other individuals in their population?

Clumped Distribution

Individuals found in groups within the habitat Seen in social species (wolves, elk, prairie dogs, etc.)

Uniform Distribution

Individuals spaced evenly due to territorial behavior

Random Distribution

Individuals spread out irregularly Example: Wind-blown seeds that germinate where they land

Biomes

Influenced by physical and climatic characteristics Particularly precipitation and temperature

Reproductive Strategy

Influences the growth potential of a species' population aka Life-History Strategy

Competition

Intraspecific and Interspecific

Population Distribution

Location and spacing of individuals within their range

Biotic Potential

Maximum per-capita rate a population could increase under ideal conditions (no environmental limits) r

Carrying Capacity

Maximum population size that can be indefinitely supported in a particular environment Determined by growth factors and can increase/decrease as resources change (K)

Mediterranean Scrub

Mild, moist winters & hot, dry summers Precipitation 250 - 500 mm/ yr. Dominated by summer drought Thin soil, often not fertile Adapted to periodic fires Dense growth of evergreen shrubs, low woodlands Mule deer, chipmunks, many species of birds

Nitrogen

Most abundant element in the Earth's atmosphere Needed to make proteins and nucleic acids (DNA/RNA)

Heat

Most energy (~90%) is released as _____, while the remaining 10% supports metabolism

Nitrogen and Phosphorus

Move in cycles heavily dependent on a wide variety of bacteria Chemicals essential for life

Carbon Cycle

Movement of carbon from the non-living environment into living things and back

Matter Cycles

Movement of life's essential chemicals or nutrients through an ecosystem

Phosphorous Cycle

Needed by all organisms to make DNA Very slow cycle - no atmospheric component Dependent only on weathering of rock

Nitrogen

Needed to make protein and nucleic acids

Population Density

Number of individuals per unit area Example: Number of wolves distributed over Yellowstone Too High: More competitive (fighting) & disease spreads easier Too Low: Hard to mate

Tundra

Nutrient poor soils - little organic material Permafrost Treeless - mostly grasses, low shrubs Low species richness

Niche Generalist

Occupies a broad niche Can utilize a wide variety of resources

Boom and bust

Occur when predator and prey populations increase and decrease

Exponential Growth

Occurs in a population when there are no limits Typically seen when a species enters a new environment or there is a new resource J-Shape

Competitive Exclusion Principle

One species excludes another from a portion of the same niche as a result Less successful species can leave the area, switch niches, or die

Ecologists

Organize life from biosphere, biome, ecosystem, community, population, and individual (largest to smallest)

Carbon

Photosynthesis and cellular respiration are how ________ moves in and out of living things

Logistic Population Growth

Population growth rate slows as the size approaches the carrying capacity Exponential growth transitions to logistic growth S-Shaped Curve

Biome

Portion of the biosphere characterized by a distinct climate and a particular assemblage of plants and animals adapted to it

Resistance Factors

Predators, competition, and diseases decrease population growth rates, causing the J curve to transition to the S curve (logistic growth)

Nitrogen Fixation

Process of converting nitrogen gas into nitrogen compounds that plants can absorb and use

Cellular Respiration

Process that releases energy by breaking down glucose and other food molecules in the presence of oxygen

Cellular Respiration

Process that releases energy by breaking down glucose and other food molecules in the presence of oxygen Producers & Consumers

P-Cycle

Provides nutrients for plant growth Impacted by humans through open-pit mining and animal waste

Deforestation

Reduces carbon uptake from atmosphere into biotic reservoirs

Burning Fossil Fuels

Releases carbon, and nitrogen from fossil fuel sinks into the atmosphere

Trophic Levels

Represent feeding levels in a food chain Organized based on what consumers eat Some feed at multiple trophic levels

k-selected species

Reproduce slowly Has lower biotic potential (r) More likely to have a stable population close to carrying capacity Less adaptable to environmental change Examples: Elk, bears, and spruce trees

Sinks

Reservoirs that accept more nutrients than they release Time Nutrients Stay = Residence Time

Producers

Set the energy budget for food in a system through photosynthesis on the trophic levels

r-adapted species

Short life Rapid growth of individual Early maturity Many, small offspring Little parental care Adapted to unstable environment Prey Niche generalists

Individual

Single member of the population

Biome

Species within each _____ are specifically adapted to the particular environmental conditions of it

Ecosystem

Specific portion of a biome consisting of the living (biotic) and nonliving (abiotic) environmental components that interact

Community Ecology

Study of all the populations Plants, animals, human affect, and other living species

Equator

Temperature decreases when moving away from the ______ and with increasing elevation

Desert

Temperature varies -20 to > 40 °C Extremely arid Precipitation < 250 mm annually Defined by lack of precipitation Soils low in nutrients and high in salts Vegetation sparse - cactus and sagebrush Animals are very small to regulate temperature

Lynx

The animal most likely to be found in the Boreal forest would be:

1 & 3

The biological community that characterizes the arctic tundra is: 1) migrating herbivores, small mammals, and predatory birds 2) large trees 3) mosses, lichens, and dwarf woody plants 4) diverse amphibians and reptiles

Limiting Factor

The critical resource whose availability determines species population size distribution

Range of Tolerance

The range of a limiting factor within which a species can survive and reproduce Population concept

Biosphere

Total area on Earth (terrestrial, marine, and freshwater.) where living things are found

Nitrogen Cycle

Transfer of nitrogen from the atmosphere to the soil, to living organisms, and back to the atmosphere

Exponential Growth

Turns into logistic growth (S curve) as population size approaches carrying capacity (K) and resistance factors begin to limit survival

Photosynthesis

Use of solar energy to combine CO2 and H2O to make sugar, releasing O2 in the process Producers only

Species Diversity

Variety of species in an area Measured by species richness (# of different species) and species evenness (relative abundance of individual species)

Complex Structure

Vertical arrangement of foliage of different trees in the tropical rainforest creates a diverse array of habitats for animals

Niche Specialist

Very specific habitat or resource requirements

Savanna

Warm, constant temperature Drought for ½ the year Precipitation: 760 -1,200 mm/yr. Seasons regulated by precipitation Soil low in nutrients from leaching Expanses of grass with occasional Acacia trees Adapted to periodic fires Herds of hoofed animals & large predators

Tropical Rain Forest

Warm, constant temperatures Growing season year-round Precipitation > 2,000 mm/ yr. High plant / animal diversity Ancient, nutrient-poor soil 3 distinct canopy layers Estimated 5-50 million species Many unique niches and endemic species

Secondary

What kind of organisms are on trophic level (TL ) 3?

Resistant Factors

What might cause a population's size to transition from exponential to logistic growth?

Random

What population distribution pattern would you expect to see in a population of dandelions whose seeds are dispersed by the wind?

Phosphorus

Which cycle does not have an atmospheric phase?

Intraspecific competition

Which of the following is demonstrated by the bird of paradise's dance?

Annual Population Growth

[(# New Births)/(# of Individuals Prior Year)] * 100