Average = 72%

Average = 74%

Exam I 2008 Your class has second highest average in 5 years! Year Average Score 2004 71 2005 65 2006 79 2007 72 2008 74

Nutrient Cycles The magic of water What is a Nutrient? The Carbon cycle The Nitrogen cycle The Phosphorus cycle The Sulfur cycle 4

The Magic of Water Life is watery! 60-70% by weight of living organisms Makes possible chemical reactions necessary for life Promotes neutrality

Polar 6

Extra OH- H+ + OH- = H2O Extra H+ CS Fig. 3.4 7

Least dense Most dense 8

The Magic of Water Polarity Life is watery! Makes possible chemical reactions necessary for life Promotes neutrality Sticks together Holds heat Large liquid temperature range Ice Floats! Evaporation provides cooling mechanism for organisms – Did you remember your deodorant today? Polarity

What are Nutrients? Elements used as building blocks in organic compounds needed to build living cells C. HOPKINS More basic than vitamins! These are the things vitamins are made of

C H O 11

12

Fig. 6.3

CS Fig. 3.13 14

Biogeochemical Cycles = Natural + Anthropogenic Fig. 6.2 Fig. 6.2 Biogeochemical Cycles = Natural + Anthropogenic ANTHROPOGENIC = HUMAN ORIGIN

ATMO- SPHERE SHORT TERM BIOTA 16

Millions to 100’s of Millions Years to Millenia LONG-TERM CS Fig. 3.15 Atmos- phere Biota Ocean Crust 17 CS Fig. 3.19

Fig. 6.6 Carbon Cycle (petagrams = 1015 grams) Natural sources = 207 Natural removals = 210 Anthropogenic sources = 6.4 – 7.4

Nitrogen Main reservoir is N2 in atmosphere Cannot be used directly by plants Necessary to build amino acids, peptides, proteins DNA!

ATMOSPHERE BIOTA ! 20

Nitrogen made available for Life N2 -> NO2- -> NO3- -> NH4+ -> Peptides and Proteins Or in words: Gas – Nitrite – Nitrate – ammonium – organic molecules

Fig. 6.11 Nitrogen Cycle (teragrams = 1012 grams) Anthropogenic = 170 - 445 Natural = 196 - 733 Eutrophication = The addition of excess nutrients to natural waters

Phosphorus P necessary for Nucleic acids Cell membranes Energy-transfer reactions Bones Teeth Source: Minerals (soil)

CRUST BIOTA 24

NATURAL CYCLE BIOTA OCEAN CRUST

CS Fig. 3.22 Phosphorus laid down as fertilizer more than what is delivered through Erosion!!

Fig. 6.12 Phosphorus Cycle in Metric Tons Anthropogenic runoff = 14 – uptake Runoff causes eutrophication Natural runoff = 25-30

Fig. 6.14 Island of Nauru after mining for phosphorus

Sulfur S important for proteins Source: Minerals (soil)

Anthropogenic = Significant! Causes Acid Rain Fig. 6.15 Sulfur Cycle in 1012 moles Anthropogenic = Significant! Causes Acid Rain

The End. Back