EOC review #2

Carbon Cycle

• Two Major Processes:– Cellular Respiration:

• O2 + Glucose CO2 + H2O

– Photosynthesis:• CO2 + H2O Glucose + O2

Nitrogen Cycle

• Nitrogen is a major component in protein and DNA

• Found in water as -ammonia (excreted by aquatic animals)-nitrites (formed by bacteria)-nitrates (formed by bacteria)

Water Cycle

1. Sun2. Clouds/Condensation3. Evaporation4. Precipitation5. Ocean6. Where can we draw

transpiration?1. Transpiration is the

evaporation of water from plants

• The initial source of energy for all organisms is

Our SunEven the energy that Carnivores get from eating their prey can be traced back to a plant.

The shape of the pyramid implies there is “less” at the top. “Less” what and why is this necessary

for success of the ecosystem? (Energy)

Ecological Pyramids• Pyramid of numbers • Pyramid of energy

Food Webs• What is demonstrated by a food

web? The feeding( trophic ) levels and the

flow of energy through an ecosystem.

• Explain the impact that removal

of a single species can have on the entire food web.

Removing just one species can collapse a food web if it is the primary food source in a community with little biodiversity. If there is a lot of biodiversity then it will not have a large effect because the higher trophic levels will move to other food sources.

Approximately how much energy absorbed by one trophic level is passed on to the next? What happens to the remaining energy?

Only 10% !!!!!!!

The rest is excreted as waste or converted to heat through cellular respiration

Draw a diagram relating photosynthesis and cell respiration. Your diagram should demonstrate how and what atoms cycle through the system, how energy flows through the system and the

cellular structures that perform each process.

On a biological level, how do we extract energy from the food that we eat? Cellular Respiration

Three forms energy takes as it passes through an ecosystem. • Light energy• Chemical energy• Heat What two purposes does food serve our cells? • Food to convert to ATP (Energy) • nutrients to be used in our cells. Why, when an organism dies, does the matter it is composed of

disintegrate yet that (hopefully) doesn’t happen while we are alive?• Once Oxygen stops circulating through the body cellular respiration

cannot take place. So tissues begin to die. As this happens decomposers start to colonize the dead organism because their defense mechanisms no longer function.

The interdependence of two or more organisms on each other is called

__________symbiosis________________.

Types of symbiosis

• Parasitism- One organism benefits the other is harmed.

• Mutualism- Both organisms benefit

• Commensalism- One benefits the other is unaffected.

Important Definitions

• Populations: A group of organisms of one species that interbreed and live in the same place at the same time

• Communities: composed of a group of organisms or a population of different species occupying a particular area,

• Ecosystems: all living organisms (biotic factors) in an area as well as its physical environment (abiotic factors)

• Biomes: A major ecological community of organisms adapted to a particular climatic or environmental condition

• Biospheres: The part of the earth where living things exist.

5 human activities that impact the ecosystem

• Burn fossil fuels• Oil spills• Deforestation• Air pollution• Water pollution• Feed lots• Pesticide use

• Because of the 10% rule the population of the organisms at the top of the food chain is controlled by the number of organisms at the bottom.

AGAIN? This must be really important!

•Which of the following is most likely to lead to an increase in the number of foxes over time?

A. a decrease in owls B. an increase in hawks C. an increase in mountain lions D. a decrease in raspberry bushes

If many trees are removed from a forest, what is the most immediate effect on the carbon cycle in that forest?

A. increased rates of decomposition B. decreased use of atmospheric CO2 C. decreased combustion of fossil fuels D. increased production of organic compounds