Cycles• Matter can cycle through the biosphere because

biological systems do not use up matter, they transform it.

• Matter is Recycled within and between the ecosystems.

• Matter is assembles into living tissues or passed out of the body as waste.

• Just think, with every breath you take, you inhale hundreds of oxygen atoms that might have been inhaled by dinosaurs millions of years ago!!

The Water Cycle

• Plants and animals need water to live• Natural processes constantly recycle water

throughout the environment– Animals breathe out water vapor, return

water to the environment through urination

– Plants pull water from the ground and lose water from their leaves through transpiration

21 The diagram shows physical changes that

occur in the water cycle. Which of these shows

condensation?A QB RC SD T

PrecipitationRun Off of ground waterEvaporation

The Carbon Cycle• All life on earth is based on carbon. Carbon is a

key ingredient of living tissue.• Begins during photosynthesis in which CO2 gas

is converted to carbon molecules• Carbon molecules are then used for energy

and growth• As heterotrophs eat plants, they also gain this

energy from carbon• When the carbon is used, CO2 is released and

returned to the atmosphere

Carbon Cycle• Glucose C6H12O6 is

produced by plants, eaten by animals.

Photosynthesis • Animals and plants

exhale CO2 which is taken in by plants to make glucose

Cellular Respiration

Nitrogen Cycle

• Lightening and bacteria in the ground “fix” Nitrogen into a form usable by plants.

• It is absorbed by plants, through their roots as nitrates, so they can be used to build amino acids essential for building proteins, enzymes and the nitrogen bases of DNA.

Phosphorus Cycle

• All organisms require phosphorus for growth

• Phosphorus cycles in two ways– In the short term cycle, phosphorus is found in

plants, animals eat plants, they die, and the phosphorus returns to the soil

– In the long term cycle, phosphorus is washed into the sea and is incorporated into rock

Another version for cycles…

WILL REWRITE

Biochemical Cycles(Nutrient Cycles)

• The paths of water, carbon, nitrogen, and phosphorous pass from the nonliving environment to living organisms and then back to the nonliving environment

Water Cycle

• Ground Water: water retained beneath the surface of the Earth

• Evaporation: water is heated by the sun and reenters the atmosphere

• Transpiration: water is drawn from stomata in leaves of plants

• Water that is not evaporated travels from plants to the atmosphere through transpiration and returns to the Earth as rain.

Carbon Cycle• Respiration: carbon dioxide is given off

as a byproduct of cellular respiration• Combustion: carbon is released when

fossil fuels are burned• Erosion: Shells of dead organisms

(made of calcium carbonate) form limestone. As limestone erodes, carbon becomes available for other organisms

Nitrogen Cycle

• 79% of the atmosphere is Nitrogen• Most organisms cannot use Nitrogen

in its atmospheric form• Nitrogen Fixation: a few bacteria

(found in the soil and on roots of some plants) have enzymes that will break down atmospheric nitrogen and form ammonia

• Assimilation: absorption and incorporation of nitrogen into plant and animal compounds

• Ammonification: the production of ammonia by bacteria during the decay of nitrogen-containing urea

• Nitrification: the production of nitrate from ammonia

• Denitrification: the conversion of nitrate to nitrogen gas

Phosphorous Cycle

• Phosphorous used in ATP and DNA• Phosphorous in rock dissolves in

water and is absorbed by plants

Renewable vs Nonrenewable Resources

• Nonrenewable: Do not replenish themselves naturally

• Renewable: Replenish themselves naturally

Ways to Conserve Nonrenewable Resources

• Alternative Fuels• Recycling (reduce, reuse, recycle)