Chapter 2 Environmental Systems

Earth is a single interconnected system All environmental systems consist of matter What are the basic building blocks of matter?

Molecules (O 2 ) Compound (CO 2 ) Fig. 2-4a, p. 38 Table 2-1, p. 38 All environmental systems consist of matter

Atoms, Ions, and Molecules Are the Building Blocks of Matter Atomic theory All elements are made of atoms Subatomic particles Atomic number Mass number Isotopes Fig. 2-5, p. 39 Model of a Carbon- 12 Atom

Table 2-2, p. 40

Matter Undergoes Physical, Chemical, and Nuclear Changes Nuclear change What is created? Half-life Why is this important to know? Fig. 2-9, p. 43

Chemical bonds

Properties of water

pH Scale Supplement 5, Figure 4 pH Measure of acidity H + and OH -

Matter Undergoes Physical, Chemical, and Nuclear Changes Physical change Chemical change, chemical reaction Law of Conservation of Matter

Organic Compounds Are the Chemicals of Life Inorganic compounds only carbon bound to elements other than hydrogen. ex. NH 3, NaCl, H 2 O, and CO 2 Organic compounds have carbon-carbon and carbon-hydrogen bonds Supplement 4, Fig. 9

DNA Double Helix Structure and Bonding Supplement 4, Fig. 10

Amino Acids and Proteins Supplement 4, Fig. 8

Glucose Structure Supplement 4, Fig. 4

Fatty Acid Structure and Trigyceride Supplement 4, Fig. 11

Matter Comes to Life through Genes, Chromosomes, and Cells The basic building blocks of LIFE Cells Chromosomes Genes Fig. 2-7, p. 42

Forms of Energy

Energy = power X time Power = energy/time Joule = 1 watt x sec

First law of thermodynamics You can’t get something from nothing.

Second law of thermodynamics When energy is transformed, the quantity of energy remains the same, but its ability to do work diminishes. Figure 2.15

Figure 2.14 Second law of thermodynamics Some systems are more energy efficient than others. Some forms of energy are higher quality than others.

Second law of thermodynamics All systems move toward randomness rather than toward order. This randomness is always increasing in a system, unless new energy from the outside of the system is added to create order.

The amount of available energy determines which organisms can live in a natural system Abundant energy Very little energy Depend on marine snow Depend on chemosynthesis

System analysis shows how matter and energy flow in the environment

Steady states System is still dynamic System is at equilibrium

Feedbacks Negative, or corrective, feedback loop Positive feedback loop Tipping point, threshold level

To what extent is Earth’s temperature regulated by feedback loops? Warmer temperatures at Earth’s surface increase evaporation of water Additional water vapor results in cloud formation Result: less heating of surface, less evaporation, less warming Result: absorb more terrestrial energy, higher surface temps, more evaporation, more warming POSITIVE NEGATIVE

System Effects Can Be Amplified through Synergy Synergistic interaction, synergy Two or more processes combine in such a way that combined effect is greater than the two separate effects Helpful Studying with a partner Harmful E.g., Smoking and inhaling asbestos particles

Managing Environmental Systems in the Florida Everglades Three key steps: increase water flow, reduce pollutants coming in, develop strategies for dealing with future problems