AP Environmental Science Unit 2

Organism, Population, Community, Ecosystem, Biosphere

What are the five levels of Organization?

Organism

One living being

Population

Many individuals of the same species

Community

many individuals of different species

Ecosystem

both the biotic and abiotic components in a habitat

Biosphere

all portions of earth where life exists

Biotic factors

Living or once living or parts of organisms

Abiotic Factors

Physical factors

Range of Tolerance

Populations thrive within certain ranges of temperature, amount of moisture, etc.

Limiting Factors

environmental factor most often in short supply

salinity, dissolved oxygen, sunlight, nitrogen, silica, iron, etc.

What is an example of limiting factor in aquatic ecosystem

one-way flow of high quality energy, round trip cycling of matter or nutrients through the biosphere, gravity.

What are the three factors that sustain life on earth?

Producers/Autotrophs

Organisms that can produce their own energy through photosynthesis or chemosynthesis

Consumers (Heterotrophs)

Organisms that can only obtain energy by eating other organisms

Primary Consumers

The second level in a food chain; only eats producers

secondary consumers

third level in a food chain

Omnivores

may eat plants or animals

Carnivores

Only eats animals; must be at least secondary consumers

Predator

Only eats animals that it has killed

Decomposers

Breaks down organic matter to inorganic compounds. Only bacteria and fungi belong to this group.

Detritovore

Breaks down dead organisms and feces to smaller organic molecules; includes earthworms, sea stars, pill bugs, flies, etc.

Ecological Pyramids

Graphical models of the quantitative differences between tropic levels of a single ecosystem

Energy Pyramid, Biomass Pyramid, Pyramid of Numbers

What are the three types of Pyramids?

Energy Pyramid

Shows flow of energy through a tropic level. (Units: Jm^2yr^-1)

10% rule

90% of energy is lost at each transfer

Conversion Efficiency

Ratio of net production at one level to that of the next.

Pyramids of Biomass

shows total mass of organisms. (Units: g/m^2/yr); can be inverted)

It becomes detritus and is decomposed

What happens to the missing mass in a biomass pyramid?

Pyramid of Numbers

how many animals are present in a food chain. (Can be inverted)

Inverted Pyramids

Can occur in pyramids of numbers and biomass; occurs more often in numbers; results from seasonal fluctuations.

Solar Radiation,Temperature, CO2, H20, Nutrients, Herbivory

What factors affect Primary Productivity

swamps/ marshes, tropical rainforest, temperate rainforest.

What biomes have high PP?

extreme desert, desert shrub, tundra

What biomes have low PP?

struggle for existence, physical and behavioral variation, survival of the fittest, species change over time.

How does natural selection happen?

Individuals with the highest ability to reproduce will pass down the favorable traits and survive longer.

What is survival of the fittest?

gene's for new traits have to already be present in gene pool, generations are too long.

Why can't humans evolve to fit changing environmental conditions?

Factors that make earth just right

earth's orbit is right distance from the sun, right size of earth and mass, resilient and adaptive, right temperature, right composition

Fundamental Niche

the part of the habitat in which species could live in the absence of competitors and predators.

Realized niche

the part it actually occupies

Allopatric speciation (geographic isolation) and sympatric speciation (temporal isolation and behavioral isolation).

What are the types of isolation and speciation?

Keystone Species

have a larger impact on the community if removed than other species

Indicator Species

gives early warning signs of damage or dangers to a community

Primary Succession

begins in a place without soil (look at notes)

secondary succession

begins in a place with soil and once home to living organisms

Climax Community

a stable group of plants and animals that is the end result of the succession process

Instrumental Value and Intrinsic Value

Why should we care about extinction?

Instrumental (Extrinsic Value)

gods and services, recreation, aesthetics, medicinally research, genetic info

Intrinsic Value

right to exist regardless of practical use to humans, Biophilia- inherent genetic kinship with the natural world.

Economic Invisibility, Insect-based pollination, rainforest medicine, ocean fisheries, flood control/drought prevention, fuelwood, mangroves-flood erosion control,

What are some examples of ecological services?

species richness and species evenness

What are the biodiversity indices?

species richness

number of total species

species evenness

abundance of individuals within each species

diversity

what do biodiversity indices measure?