Science, Systems, Matter, and Energy Chapter 3 Science, Systems, Matter, and Energy

Core Case Study: Environmental Lesson from Easter Island Figure 2-1

THE NATURE OF SCIENCE What do scientists do? Collect data. Form hypotheses. Develop theories, models and laws about how nature works. Figure 2-2

Scientific Theories and Laws: The Most Important Results of Science Scientific Theory Widely tested and accepted hypothesis. Scientific Law What we find happening over and over again in nature. Figure 2-3

What are the steps in the scientific process. What is a variable What are the steps in the scientific process? What is a variable? Can you test analyze more than one variable at a time? What is a paradigm shift?

Scientific Reasoning and Creativity Inductive reasoning Specific to general Bottom-up reasoning going from specific to general. Deductive reasoning General to specific Uses logic to arrive at a specific conclusion. Top-down approach that goes from general to specific.

Scientific Reasoning and Creativity Newton's Law. Everything that goes up must come down. And so, if you kick the ball up, it must come down. I've noticed previously that every time I kick a ball up, it comes back down, so I guess this next time when I kick it up, it will come back down, too.

Frontier Science, Sound Science, and Junk Science Frontier science has not been widely tested (starting point of peer-review). Sound science consists of data, theories and laws that are widely accepted by experts. Junk science is presented as sound science without going through the rigors of peer-review.

Limitations of Environmental Science Inadequate data and scientific understanding can limit and make some results controversial. Scientific testing is based on disproving rather than proving a hypothesis. Based on statistical probabilities.

What is a feedback loop? What is the difference between positive and a negative feedback? What is homeostasis? What is a synergistic interaction?

Feedback Loops: How Systems Respond to Change Outputs of matter, energy, or information fed back into a system can cause the system to do more or less of what it was doing. Positive feedback loop causes a system to change further in the same direction (e.g. erosion) Negative (corrective) feedback loop causes a system to change in the opposite direction

TYPES AND STRUCTURE OF MATTER What is matter? What is an element? What is a compound? What are the 3 types of bonds? What is an atom?

If you change the number of protons in an element you get an ________ If you change the number of neutrons in an element you get an________ If you change the number of electrons in an element you get an________ How are protons, neutrons, and electrons charged? How is pH measured?

The pH (potential of Hydrogen) is the concentration of hydrogen ions in one liter of solution. http://www.quia.com/rd/1975.html?AP_rand=296212047 Figure 2-5

The concentration of H+ ions in a solution with a pH value of 4 is how many times as great as the concentration of H+ ions in a solution with a pH value of 7? A 1 B 10 C 100 D 1,000 E 10,000

Organic Compounds: Carbon Rules Organic compounds contain carbon atoms combined with one another and with various other atoms such as H+, N+, or Cl-. Contain at least two carbon atoms combined with each other and with atoms. Methane (CH4) is the only exception. All other compounds are inorganic.

Organic Compounds: Carbon Rules Hydrocarbons: compounds of carbon and hydrogen atoms (e.g. methane (CH4)). Chlorinated hydrocarbons: compounds of carbon, hydrogen, and chlorine atoms (e.g. DDT (C14H9Cl5)). Simple carbohydrates: certain types of compounds of carbon, hydrogen, and oxygen (e.g. glucose (C6H12O6)).

Cells: The Fundamental Units of Life Cells are the basic structural and functional units of all forms of life. Prokaryotic cells (bacteria) lack a distinct nucleus. Eukaryotic cells (plants and animals) have a distinct nucleus. Figure 2-6

What are the 3 major types? What is a polymer? What are the 3 major types? Figure 2-7

Carbohydrate A monomers of amino acids linked together B 2 or more monomers of simple sugars linked together C sequence of nucleotides linked together Protein Nucleic Acid

A positive feedback loop is illustrated by all of the following except A compound interest in a savings account B exponential population growth C the greenhouse effect D a thermostat E none of the above

A negative feedback loop is illustrated by all of the following except A decelerating loss of heat as a pan is removed from the stove B sweating to cool your body down during and after vigorous exercise C cancer D a thermostat

Which of the following is an example of synergism? A Secondary smoke may increase the risk of lung cancer in a nonsmoker B The combined effects of alcohol and a depressant produce a greater effect than would be expected C When exponential growth of the human population exceed carrying capacity, a massive dieback will occur D The use of antibiotics reduces the effectiveness of birth control pills

Which of the following statements DOES NOT describe the scientific enterprise? A Science is the acceptance of what works and the rejection of what does not. B Established scientific theories are not challenged and continue to hold true. C Advances in science are often based on disagreement, speculation, and controversy. D Scientific laws are based on statistical probabilities, not certainties. E Science attempts to reduce the degree of uncertainty and lack of objectivity.

What is a nucleotide. What is a gene. What is a chromosome What is a nucleotide? What is a gene? What is a chromosome? What is a genome?

States of Matter The atoms, ions, and molecules that make up matter are found in three physical states: A fourth state, ______, is a high energy mixture of positively charged ions and negatively charged electrons.

CHANGES IN MATTER Matter can change from one physical form to another or change its chemical composition. Law of conservation of matter. Physical change Chemical change Chemical equations are used to represent the reaction. What is matter quality?

Chemical Change Energy is given off during the reaction as a product.

Types of Pollutants Factors that determine the severity of a pollutant’s effects: chemical nature, concentration, and persistence. Pollutants are classified based on their persistence: Degradable pollutants Biodegradable pollutants Slowly degradable pollutants Nondegradable pollutants

Nuclear Changes: Radioactive Decay Natural radioactive decay: unstable isotopes spontaneously emit fast moving chunks of matter (alpha or beta particles), high-energy radiation (gamma rays), or both at a fixed rate. Radiation is commonly used in energy production and medical applications. The rate of decay is expressed as a half-life (the time needed for one-half of the nuclei to decay to form a different isotope).

Nuclear Changes: Fission Nuclear fission: nuclei of certain isotopes with large mass numbers are split apart into lighter nuclei when struck by neutrons. Figure 2-9

Nuclear Changes: Fusion Nuclear fusion: two isotopes of light elements are forced together at extremely high temperatures until they fuse to form a heavier nucleus. Figure 2-10

ENERGY Energy is the ability to do work and transfer heat. What is Kinetic energy What is Potential energy What is entropy? What is energy efficiency/productivity? What % of energy used in the US ends up doing useful work?

ENERGY LAWS: TWO RULES WE CANNOT BREAK The first law of thermodynamics The second law of thermodynamics When energy changes from one form to another, it is always degraded to a more dispersed form. What is Energy efficiency

Mechanical energy (moving, thinking, living) Chemical energy (photosynthesis) Chemical energy (food) Solar energy Waste Heat Waste Heat Waste Heat Waste Heat Figure 2.14 The second law of thermodynamics in action in living systems. Each time energy changes from one form to another, some of the initial input of high-quality energy is degraded, usually to low-quality heat that is dispersed into the environment. Fig. 2-14, p. 45

SUSTAINABILITY AND MATTER AND ENERGY LAWS Unsustainable High-Throughput Economies: Working in Straight Lines Converts resources to goods in a manner that promotes waste and pollution. Figure 2-15

Sustainable Low-Throughput Economies: Learning from Nature Matter-Recycling-and-Reuse Economies: Working in Circles Mimics nature by recycling and reusing, thus reducing pollutants and waste. It is not sustainable for growing populations.

In order to make 1 plastic soda bottle, ~100L of crude oil are used, 100kg of steel, 100L of H2O, and various amounts of other materials; therefore, A plastic bottles have high resource productivity B plastic bottles have low material efficiency C plastic bottles represent an efficient use of materials D Most of the matter used to manufacture plastic bottles ends up in the bottle

Which of the following is not an example of a physical change? A confetti is cut from a piece of paper B Water evaporates from a lake C Ice cubes are formed in the freezer D A plant converts CO2 into carbohydrates E A tree is cut down

All of the following statements can be concluded from the law of conservation of matter except A We cannot throw anything away because there is no “away” B There will always be pollution of some sort C We will eventually run out of matter if we keep consuming it at current rates D Everything must go somewhere E We do consume matter

Of the following options to deal with nondegradable pollutants , the LEAST effective is to A remove it from the contaminated air, water, or soil B reuse them C recycle them D refrain them from introducing them into the environment

Energy input A usually greater than energy output B always greater than energy output C always equal to energy output D usually less than energy output E always less than energy output

Which of the following comparisons of nuclear fusion and nuclear fission is correct? A Nuclear fusion produces less energy than fission. B Both nuclear fusion and fission produce the same amount of energy. C Nuclear fusion occurs in nuclear power plants, whereas nuclear fission occurs in the sun. D Nuclear fusion occurs in in atomic bombs, fission occurs in hydrogen bombs. E Nuclear fusion is harder to initiate than fission.

Most of today’s advanced industrialized countries have A matter-recycling-and-reuse economies B low-throughput economies C high-throughput economies

The data shown were collected in a laboratory experiment in which the effect of pH on the survival of Tardigrades was examined. In each trial, 50 live Tardigrades were added to a solution with a pH as indicated. After two hours, observations were made to determine the number of Tardigrades remaining alive in the sample. The pH at which 50% of the Tardigrades survive after 2 hours of exposure can be predicted from the data. This pH is 2.5 3.8 4.5 5.0 6.2

The data shown were collected in a laboratory experiment in which the effect of pH on the survival of Tardigrades was examined. In each trial, 50 live Tardigrades were added to a solution with a pH as indicated. After two hours, observations were made to determine the number of Tardigrades remaining alive in the sample. How would including a control group be useful in this experiment? It would provide a reference for the effects of random environmental factors. It would provide a number against which percentages can be computed. It would provide a value for which the standard pH can be measured. It would provide a standard number to test for statistical uncertainty. It would provide an end data point for graphical analysis.

The data shown were collected in a laboratory experiment in which the effect of pH on the survival of Tardigrades was examined. In each trial, 50 live Tardigrades were added to a solution with a pH as indicated. After two hours, observations were made to determine the number of Tardigrades remaining alive in the sample. On the basis of the data, the best prediction of the pH of the water in which Tardigrades normally are found in the wild is 3 4 5 6 7