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Chapters 1-2-3-4. Quick review for the quiz on the fourth day of classes AP Biology Condensed from the full ch 1-2-3-4 power point presentations. Homeostasis Fig 1.8. Feedback mechanisms of living things Negative Ex. Blood glucose levels Body temp. Positive Ex. Breast feeding
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Chapters 1-2-3-4 • Quick review for the quiz on the fourth day of classes • AP Biology • Condensed from the full ch 1-2-3-4 power point presentations
HomeostasisFig 1.8 • Feedback mechanisms of living things • Negative Ex. • Blood glucose levels • Body temp. • Positive Ex. • Breast feeding • Blood clotting
Elements and Life • Define element: • Compound: • SPONCH CaK • ( ONCH 96% ) • Trace elements (Fe, I) • anemia, goiter—iodized salt, sea weed • Crops too—nitrogen, calcium
Fig 2.7 Energy Levels of Electrons • light• fluorescence• photo-synthesis Energy Absorbed Energy Lost
Structure / Function Examples Mimic Molecules Ex: morphine
Water’s polarity and hydrogen bonds • Account for its unique properties that contribute to the fitness of Earth’s as an environment for life.
Cohesion/Adhesion • Cohesion is water’s attraction to water • Adhesion is water’s attraction to other substances • Surface tension • Water transport in plants
Stabilize temperatures • High specific heat • Water moderates global and organismal temperatures • Evaporative cooling is important for animals as well as plants
Expansionupon freezing • Because of Hydrogen bonding … • 0° C Ice is less dense than liquid water • Bodies of water would freeze solid
VersatileSolvent: • Ex: Salt and water • Ionic and polar com-pounds dissolve in water
Even very large molecules like proteins dissolve in water as long as there are areas of ionic or polar regions.
The pH scale • pH=The measure of H+ and OH- in a solution. • Scale 0-14 • Acids=increase the H+ concentration • Bases=reduce the H+ concentration
pH = -log[H+] • Neutral = 10-7[H+] • pH 9 has H+ concentration of 10-9 M and an OH- concentration of 10-5 M • What are Buffers?