EOC Review Part 4: Interdependence and Flow of Matter and Energy-All Life Is Interdependent

EOC Review Part 4: Interdependence and Flow of matter and Energy-All life is interdependent and interacts with the environment, while matter cycles and energy flows through all ecosystems.

SPI 3210.2.1 Predict how population changes of organisms at different trophic levels affect an ecosystem.

SPI 3210.2.2 Interpret the relationship between environmental factors and fluctuations in population size.

SPI 3210.2.3 Determine how the carrying capacity of an ecosystem is affected by interactions among organisms.

SPI 3210.2.4 Predict how various types of human activities affect the environment.

SPI 3210.2.5 Make inferences about how a specific environmental change can affect the amount of biodiversity.

SPI 3210.2.6 Predict how a specific environmental change may lead to the extinction of a particular species.

SPI 3210.2.7 Analyze factors responsible for the changes associated with biological succession.

SPI 3210.3.1 Interpret a diagram that illustrates energy flow in an ecosystem.

SPI 3210.3.3 Compare and contrast photosynthesis and cellular respiration in terms of energy transformation.

SPI 3210.3.4 Predict how changes in a biogeochemical cycle can affect an ecosystem.

-Food chains and food webs show how energy flows through an ecosystem. Energy flow is in one direction the arrows in the food chains and webs show the direction that the energy flows.

Sun → Grass → Mice → Hawk

Energy for all life originates with the sun. 1st Law of Thermodynamics says that energy cannot be created nor destroyed, but can be converted from one form (ex. Solar) to another (ex. Chemical). 2nd Law of Thermodynamics says that when energy is converted from one form to another, some energy is lost as heat energy. (this is why a living person feels warm to the touch and a corpse feels cold; a corpse no longer utilizes energy)

Producers, also known as autotrophs, use solar energy to make glucose (food) through photosynthesis.

Consumers, also known as heterotrophs, cannot make their own food and must bring in energy from another source usually by eating another organism. (primary consumers eat plant material –herbivore; secondary, tertiary and quaternary consumers eat other animals and possibly plants too- carnivores and omnivores)

An ecosystem has this hierarchy:

Organisms → Species→Population→Community →Ecosystem→Biosphere

*Organisms are living things

*Species are organisms that can interbreed

*Population is all the organisms of one species in a given area

*Community is made up of all the populations (groups of different species) in a given area

*Ecosystem is made up of the communities and the Abiotic factors they interact with (water, soil, etc)

*Biosphere is the portion of the planet that contains all organisms (life)

Organisms can live in a certain place in their ecosystem; where they live is their “habitat”; what the organism does in the ecosystem is it’s “niche” (ex. Squirrel lives in trees (habitat) and there it collects nuts (niche)

Decomposers finish off food chains by breaking down dead organisms or their waste and returning those materials to the Earth to be reused. (bacteria, fungi like mushrooms)

Symbiotic relationship are close associations between members of different species.

(1) mutualism is a relationship in which both species benefit (cleaner fish and shark)

(2) commensalism is a relationship in which one species benefits while the other is neither helped

nor harmed (Spanish moss hanging in trees; benefits the moss, tree is unaffected)

(3) Parasitism is a relationship in which one species is benefited while the other is harmed (tick on dog)

Copy food chain, food web and energy pyramid.

Each level is called a “trophic” or feeding level; approximately 10% of the energy at one level is transferred to those organisms at the next level; the other 90% is either used by the organism or lost as heat during energy conversion

There are factors that limit the growth in an ecosystem; there are biotic and Abiotic factors; “Biotic” factors are those things that are living (plants, animals, food); “Abiotic” factors are nonliving things (soil, amount of water, light)

If there are not sufficient materials (carrying capacity the max number of organisms that can be sustained) then organisms will die off from starvation, being eaten, lack of shelter or water. A species can drop in number to the point of becoming “threatened” or “endangered”. After endangerment would come extinction (all have died).

Nutrients cycle. Water, Nitrogen, Phosphorus, Carbon and Oxygen are all materials necessary for life that are continually cycled throughout the biosphere.

Water cycle- evaporation, condensation, precipitation, water can also enter the cycle through transpiration, extraction (sweat and urine) and respiration.

Nitrogen cycle- producers take in nitrogen compounds in the soil and pass them to consumers that eat them; decomposers break down remains or wastes and return the nitrogen to the atmosphere; bacteria must “fix” the bacteria so it can be used by the producers again. Nitrogen fixing (nitrifying) bacteria. Legumes (beans) have these bacteria in nodes on their roots.

Phosphorus is mainly in rock and must be put into the cycle through weathering and erosion for the producers to take up and use.

Biomes are ecosystems found in certain geographic areas due to climate (affected by altitude and latitude).

Aquatic biomes are based on flow of water, depth of water, temperature, and chemicals such as salt.

*Marine- oceans, saltwater, large biodiversity

*Freshwater- lakes, streams, rivers, marshes, low biodiversity

Terrestrial biomes are based on geography, rainfall and temperature

*Tropical Rain forest- lots of different plants and animals (high biodiversity); warm, moist year round

*Savanna- grasslands with few trees, warm year long, rainy periods usually borders desert (lion king)

*Desert- hot, dry(arid), little rainfall, often hot days and cold nights

*Temperate grassland- variety of grasses, cold winters (blizzards), warm summers, periodic rainfall

*Taiga (boreal or coniferous forest)- Evergreens/Christmas trees, cold winters short summers borders tundra

*Tundra- cold, permafrost, ice and snow most of the year; very dry; treeless; most animals migrate

Humans affect ecosystems by:

Hunting, fishing to the point of extinction; farming, industry and urban development destroy habitats;

Pollution of air, water and soil

Global warming, pesticide run off cause disturbances in the cycles.

Ecosystems can undergo change of longs period of time; this is called “ecological succession”

Primary succession is where barren land develops into soil and progresses to a stable ecosystem; the first organisms to live there (pioneer species) are usually lichens; the stable ecosystem is the “climax community”.

Secondary succession take place after an ecosystem has been destroyed or disrupted by a natural disaster (ex. Fire or flood) or possibly human interaction

Pioneer species are usually grasses and weeds since soil is already there. Climax community is the the stable ecosystem after many years. Secondary succession occurs more quickly than primary succession since the soil is already there.

1. A tundra food web is shown below. Wht would most likely happen if the lemming population significantly decreased?

a. the bird population would increase b. the rabbit population would increase

c. the ermine population would decrease d. the arctic fox population would decrease

2. A desrt food chain is shown. Wht would likely be the result if a pesticide is used to reduce the number of harvester ants?

a. increase in snakes and decrease in hawks b. decrease in snakes and an increase in hawks

c. decrease in mesquite bushes and an increase in horned lizards d. increase in mesquite bushes and decrease in horned lizards

3. Global warming has led to a decrease in ice in both the Arctic and Antarctic regions. The table below