Write everything that is underlined Section 13-5 “Cycles” Write everything that is underlined

KEY CONCEPT: Matter cycles in and out of an ecosystem.

I. The Water Cycle 1. The hydrologic, or water cycle is the circular pathway of water on Earth. precipitation condensation transpiration evaporation water storage in ocean surface runoff lake groundwater seepage

2. Key terms for the water cycle: Precipitation: moisture that falls to the ground (rain, snow, sleet, hail) Evaporation: changing from liquid to gas (water to water vapor) Transpiration: plants give off water vapor from their leaves to the air Condensation: changing from gas to a liquid (little water droplets form on the outside of a cold glass of lemonade - that’s condensation)

II. Oxygen Cycle: 1. Plants make food by photosynthesis They use carbon dioxide (CO2) to make oxygen (O2) 2. Animals breathe out carbon by respiration They use oxygen (O2) and breathe out carbon dioxide (CO2) By the way … humans are animals too

Example: Oxygen Cycle: respiration carbon dioxide photosynthesis

Activity Draw, label, color, and explain the water cycle and oxygen cycles on a sheet of paper. Page 413 figure 13.12 & 13.13 Due tomorrow

1. Carbon is the building block of life. III. Carbon Cycle 1. Carbon is the building block of life. The carbon cycle moves carbon from the atmosphere, through the food web, and returns to the atmosphere. Carbon is emitted by the burning of fossil fuels (like oil, gasoline, and coal)

Carbon Cycle: notice photosynthesis and respiration are back … they both involve CO2 (now we’re looking at the C for carbon) fossil fuels photosynthesis carbon dioxide dissolved in water decomposition of organisms respiration carbon dioxide in air combustion

IV. The Nitrogen Cycle The nitrogen cycle mostly takes place underground. Some bacteria convert gaseous nitrogen into ammonia through a process called nitrogen fixation. Some nitrogen-fixing bacteria live in nodules on the roots of plants; others live freely in the soil. nitrogen in atmosphere animals denitrifying bacteria nitrifying ammonium ammonification decomposers plant nitrogen-fixing bacteria in soil bacteria in roots nitrates nitrites

Nitrifying bacteria change the ammonium into nitrate. Ammonia released into the soil is transformed into ammonium. Nitrifying bacteria change the ammonium into nitrate. nitrogen in atmosphere animals denitrifying bacteria nitrifying ammonium ammonification decomposers plant nitrogen-fixing bacteria in soil bacteria in roots nitrates nitrites Nitrogen moves through the food web and returns to the soil during decomposition.

Phosphate is released by the weathering of rocks. V. Phosphate Cycle Phosphate is released by the weathering of rocks. Phosphorus leaches into groundwater from the soil and is locked in sediments. Both mining and agriculture add phosphorus into the environment. geologic uplifting rain weathering of phosphate from rocks runoff sedimentation forms new rocks leaching phosphate in solution animals plants decomposers phosphate in soil

Activity Draw, label, color, and explain the Carbon and Nitrogen cycles on a sheet of paper. Page 414-115 figure 13.14 & 13.15 Due tomorrow

Review Questions 13.5 Cycling of Matter What is the key concept of this unit? Define the key terms for the water cycle. What do plants take in and then give out. What do animals take in and give out? How does the carbon cycle move carbon? Where is carbon emitted? Where does the nitrogen cycle take place What are phosphates released by?