Long Descriptions for Chapter Seven

Figure 7.1. Conceptual Flow of Instructional Segments in Example High School Three-Course Model Living Earth

In the middle are the words "3 Course Model" and under that "The Living Earth." Around those words are the icons for each instructional segment (as described just above) with the titles of the instructional segment. Each IS is followed by an arrow pointing to the next IS. At the top is Ecosystems then moving clockwise is Earth's atmosphere: Photosynthesis and Respiration; then Evolution; then Fossil Evidence and Plate Tectonics; then Inheritance and Variation in Traits; then Structure and Function: Cells to Organisms; then Climate Change and Ecosystem Dynamics; and then back to the beginning with Ecosystems.

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Figure 7.2. The Carbon Cycle Includes Biotic and Abiotic Processes

Drawing of a river flowing to the ocean. On the right bank, there are many plants, a few small houses, rocks, and sand. There are palm trees with the notation ‘Respiration’ within an arrow pointing up to 120 Gt/year, and ‘Photosynthesis’ within an arrow pointing down to 122.5 Gt/Year. This side is labeled Land Biomass. On the river, there is an arrow pointing up with ‘Escapes’ pointing to 77.5 Gt/Year and an arrow pointing down with ‘Dissolves’ pointing to 80 Gt/Year. The water is labeled ‘Ocean.’ The air is labeled ‘Atmosphere.’ On the left bank are factories, a corn field with a tractor, and cows grazing. The factories have smoke coming out of them. This side is labeled ‘Human Activities.’ There is an arrow pointing up to nine Gt/Year. On the tractor there is an arrow pointing up to one Gt/Year. Fossil Fuels are pictured underground. Changes to Ecosystem’ just under the farming activities. There is a jet in the sky over the factories. There is a note in the lower left corner: Units are gigatons of carbon per year. One gigaton – one billion tons.

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Figure 7.3. Phenomena Illustrating Relationship Between Photosynthesis and Respiration

There are two elements to this figure. On the left is a sealed glass ecosphere containing water, coral, algae, and brine shrimp. On the right is a line graph titled Mauna Loa Monthly Averages for CO₂ Output. The y-axis is CO₂ and ranges from 386 to 408 with increments of two parts per million (ppm). The x-axis is time in dates from January 2011 to January 2016 in one-year increments. There is a pattern of peaks and valleys. In January 2011 it was 387 ppm, in June of 2011 the CO₂ output was about 394 ppm. Around January 2012 CO₂ output was about 389 ppm, then in June 2012 it went back up to about 397. This pattern of a high output in June and a lower output in January continues with a slight increase each year. It has increased almost the same amount every year (three to four ppm increase). The last measurement on the graph, around June 2016, shows an output of about 407 ppm of CO₂.

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Figure 7.4. Models of Photosynthesis and Respiration

There are two panels, the one on the left shows a chemical equation at the top: C_xH_yO_z + O₂ (double headed arrow) CO₂ + H₂O + Energy. Under the left side of that equation is the label “Food.” Under that is a flow of energy and matter, and starting on the left side, oxygen comes into the system from plants, humans consume oxygen (and plants) and give off energy, CO₂, and water. The energy and water go into the environment and CO₂ is taken up by plants along with sunlight energy and water. The plants then give off oxygen that cycles back to humans and the process starts all over again. On the right side of the figure is a picture of a leaf receiving energy in the form of sunlight. On the leaf is written 6 H2O + 6 CO₂ with an arrow pointing to C₆H₁₂O₆ + 6 O₂ (Glucose) and an arrow pointing back to the first equation.

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Figure 7.5. CO₂ and O₂ in the Atmosphere

This is a double-line graph. The y-axis is labeled percent in atmosphere and ranges from zero to 50 in increments of 10. The x-axis is labeled Billions of years ago and ranges from 4.5 on the left to zero (now) on the right in 0.5 billion-year increments. The key is at the top of the graph. CO₂ is represented by a thinner blue line and O₂ is represented by a thicker green line. Both gases begin at zero when Earth forms more than 4.5 billion years ago. As life evolves around 3.9 billion years ago, O₂ stays near zero as CO₂ rises to its peak around 3.3 billion years ago when photosynthesis first happened (cyanobacteria), then steadily declines to near zero now. CO₂ is near zero by 2 billion years ago when there is a boom in photosynthesis. O₂ begins to rise about 2.5 billion years ago; and then O₂ rose sharply beginning about 0.6 billion years ago when land plants evolved, to a peak of about 33% about 0.4 billion years ago. Oxygen sharply declined quickly to about 20% now. A note in the graph reads “CO₂ decreases as O₂ increases.”

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Figure 7.6. Tuolumne Table Mountain Near Jamestown

This figure is comprised of five panels showing the r Plate Motions of rock over nine million years. The first panel is labeled Le Conte’s sketch. There is a sketch of Table Mountain with a dotted line swooping under the flat top of the mountain showing previous levels of rock. The second, third, and fourth panels are all labeled Le Conte’s Mental Model. Time 1 shows an ancient river channel between two hills. Time 2 shows the same channel but now that channel is filled with lava forming an ancient valley floor. Time 3 shows how the mountain looks today with the softer valley rock eroded away and the hard volcanic rock remaining to form a solid block on top of the ancient valley floor. The fifth panel show a photograph of Table Mountain showing how much rock has eroded in nine million years. The top of the mountain is labeled ancient valley floor and the base of the mountain is labeled current valley floor.

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Figure 7.7. Coastal Bluff Changes Over Time

This figure is comprised of four photographs of the same apartment building taken from the same vantage point over time. The first is labeled 2002, and the second 2008. This pair of photos is captioned Very little erosion 6 years. The third photo is labeled 2009, and the fourth 2010. This pair is captioned Lots of erosion one year! The cliff that supports the building has eroded greatly in the fourth photo and has nearly reached the building.

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Figure 7.8. Tree of Life

Chart of the Evolutionary Tree of Life. This evolutionary tree encompasses all living species on Earth. The common ancestor (the base of the tree) gave rise to three great branches: bacteria, microbes known as archaea, and eukaryotes (a group of species that includes us). The lengths of the branches reflect how much the DNA of each lineage has diverged from their common ancestor. They demonstrate that most of life's genetic diversity turns out to be microbial. The entire animal kingdom (shown at the upper right) are just a few twigs at one end of the tree. This is a branching tree diagram. On the Bacteria branch from bottom to top are: Aquifex, Thermotagales, Flavobacteria, Cyanobacteria, Chloroplast, Purple bacteria, and Chloroflexus. On the Archaea branch from bottom to top are: Pyrodictium, Thermoproteus, Thermococcus, Methanococcus, Methanothermus, and Halophiles. Branching off from the Archaea are the Eukarya including from bottom to top: Diplomonads, Microsporidia, Trichonomads, Flagellates, Entoamoebae, Slime molds, Ciliates, Diatoms, Plants, Animals, and Fungi.

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Figure 7.9. Two Pictorial Models of the Stages of the Cell Cycle

Pie chart of the stages of mitosis. The size of the pie wedge is proportional to the time spent in each phase. It shows that a cell spends most of its time, 66%, in the G1 phase and about the same amount of time in each of the other three phases: Synthesis (S) phase, Gap 2 (G2) phase, and Mitotic (M) phase.

The second diagrams show the cell cycle can be divided into two stages: Interphase (consisting of G1, S, and G2) and the Mitotic phase. Most cells spend a majority of their life in G1 of Interphase, which is when the cell is performing the functions of its cell type (e.g.: a cardiac muscle cell in G1 is helping operate the heart and a plant root cell in G1 is involved in water transport). Once a cell in G1 commits to dividing, it enters the S phase, which is when DNA replicates exactly. Once the DNA is replicated, the cell can no longer perform as a “normal” cell; therefore, it enters the G2 phase and continues to prepare for mitotic cell division. Once all steps are taken to prepare for division, the cell enters the M phase, consisting of mitosis (nuclear division) and cytokinesis (cytoplasmic division). The end result of the M phase is two identical daughter cells, each of which contains an exact copy of the DNA.

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Figure 7.10. Two Graphs of the Decline of Tuberculosis What Caused the Tuberculosis Death rate to decline?

At the top is a line graph. The y-axis is labeled Deaths per 100,000 people and ranges from zero to 700 in increments of 100. The x-axis is Year and ranges from 1820 to 2020 in 20-year increments. The graph notes that from 1820 to around 1860 ‘Infrequent historical records available.’ The data starts at 650 deaths per 100,000 in 1820 and declines until around 1850 (500 deaths) when it begins to increase to about 550 deaths in 1860. At this point on the graph it is noted that Nightingale promotes hospital cleanliness. From this point the number of deaths declines sharply to about 350 deaths per 100,000 people and continues to decline to what appears to be near zero by 1955. Milestones are noted along the graph: Around 1885 Koch discovers TB bacteria; around 1925 the first TB vaccine is available; and around 1950 the antibiotic of TB is first tested. In a second line graph we see the same information (deaths from TB per 100,000 people), but for various countries on the same grid (Finland, Brazil, UK, Canada, and USA from top to bottom; Finland shows the most deaths and USA showing the fewest). All countries show a decline in deaths after the antibiotic for TB was first tested around 1948.

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Figure 7.11. A Reinforcing Feedback in Earth’s Climate

An upward spiral changing in color from grey at the bottom to red to black at the top. Noted on the diagram, Temperature increases (one up arrow) leads to Melting Ice (one up arrow), which leads to Absorption of Sunlight (one up arrow), which leads to increase in Temperature (two up arrows), which leads to Melting Ice (two up arrows), which leads to Absorption of Sunlight (two up arrows), which leads to increase in Temperature (three up arrows), which leads to Melting Ice (three up arrows), which leads to Absorption of Sunlight (three up arrows), and finally leads to increase in Temperature (four up arrows).

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Figure 7.12. A Counterbalancing Feedback in Earth’s Climate System

Beginning at the bottom left: Temperature increase leads to Fusion increase, which leads to Star expands, which leads to Temperature decrease, which leads to Fusion decrease, which leads to Star contracts (Gravity), which leads to Temperature increase, and then around again.

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Figure 7.13. Human Impacts on the Earth System Related to Climate Change

This is a diagram on global warming and climate change. Burning fossil fuels leads to More CO₂ in Atmosphere. This leads to More CO₂ in Ocean, which leads to more hydrogen and ocean acidification. More CO₂ in the atmosphere also leads to Higher Air and Ocean Temperatures that leads to Sea Level Rise and Changing Rain Patterns.

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Figure 7.14. Temperature Forecast for Habitat of the Pika

Screenshot of an interactive tool showing a color-coded map of temperature change in California.  At the bottom of the map is a key to the color code titled Degrees Changed. From bottom to top: light yellow indicates a change of 4.8 degrees Fahrenheit, darker yellow means a change of 5.4 degrees, orange means a change of 6.1 degrees, orange-red means a change of 6.7 degrees, and dark red means a change of 7.3 degrees. The map shows the location of most of the major cities in California. The color indicates the least change along the coast and the largest change along the eastern part of the state. On the right side of the figure is a double-line graph showing the data for the Coleville area (at 5,147 feet elevation). The graph shows two scenarios: a green line for Low Emissions and GCM Range, and a red line for High Emissions and GCM Range. (GCM stands for General Circulation Model). The y-axis has degrees Fahrenheit from -3.0 to 12.0 in three-degree increments. The x-axis is marked in years from 1960 to 2080 in 20-year increments. The graphs for the two scenarios coincide until about 2040 when the High Emission line continues going up and the Low Emission line increases only very slowly.

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Figure 7.15. Diversity of Marine Mammals Over the Last 60 Million Years

Graph showing when different marine mammals evolved. A complicated graph with four lines and two different y-axes. All of the lines are plotted on the same x-axis of time from 60 million years ago up to the present day. Three different marine mammal species are shown: whales (dotted light blue line), seals (thick purple line), and manatees (thin dark blue line). Their lines correspond to the left-hand y-axis counting the diversity of each species in "number of genera," which ranges from zero to 100 in 10-genera increments. The fourth line (red) shows the average global temperature during this same time period. It corresponds to the right-hand x-axis (Average Global Surface Temperature in degrees Celsius ranging from zero to 30 in five-degree increments).

Students find that whales and manatees evolved at nearly the exact same time ~50 million years ago, thrived for about 10 million years, and then started to die off. The diversity then explodes dramatically to a peak around 10 million years ago (around the same time that seals first evolved), only to have all three types of marine mammals collapse simultaneously a few million years later.

Global temperatures got very hot around 50 Ma. They stay relatively flat until around 15 Ma, but then start cooling off. At about 4 Ma, the temperature drops quickly, which corresponds visually to the time when whales really become less diverse.

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Figure 7.16. Concept Map Illustrating Cause-and-Effect Relationships

A concept map showing the relationships that may have caused marine mammal evolution. The concept map begins with Global warming that causes a bloom in sea life and stresses Land-based Pakicetus. The Bloom in Sea life means abundant food in the water for land-based Pakicetus and Land–based Prorastomus. The Land-based Pakicetus evolve into Whales and the Land-based Prorastomus evolve into Manatees.

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Figure 7.17. Extended Concept Map Showing Chains of Cause and Effect

Four very complicated concept maps labeled A, B, C, and D.

Concept Map A. This concept map is the same as figure 7.16, but has additional geosphere concepts prior to Global Warming. Plate motions open the Tethys Sea enabling new Ocean currents that change and cause Global warming. Global Warming causes a Bloom in Sea Life and also stresses the Land-based Pakicetus and Land-based Prorastomus. Pakicetus evolved into Whales and Prorastomus evolved into manatees. This branch implies that global warming is the root cause of marine mammal evolution.

Concept Map B. Plate motions close the Tethys Sea, which blocks some Ocean currents that change and cause Global cooling. This stresses populations and causes a decline in biodiversity. A feedback mechanism from this decline links to Greenhouse gases, which decrease and further reinforce the global cooling.

Concept Map C. Human activities are the focus of this concept map. Human activities increase global warming, which amplifies El Niño changing ocean temperatures that affect fish eaten by marine mammals. Human activities can also directly harm marine mammals. Lastly, human activities include laws protecting Marine Mammals.

Concept Map D. This map begins with the end of the most recent Ice Age and the climate naturally warming. This warming stresses the Stellar's Sea Cow and allows expansion of human hunting over the last 10,000 years. Ancient human hunters and modern European explorers both kill the Stellar's Sea Cow. All three of these factors together led to the extinction of the Stellar’s Sea Cow.

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Figure 7.18. Sea Lion Pup Population and El Niño Intensity

A double-line graph plotting the number of sea lion pups born along with the intensity of the El Niño. The left-hand y-axis is labeled Sea lion pups born in USA and ranges from zero to 70,000 in 10,000-pup increments. The right-hand y-axis is labeled El Niño Intensity (dimensionless index) and ranges from -9 to one in increments of two. The x-axis is labeled Year and ranges from 1970 to 2020 in five-year increments. The El Niño intensity is graphed in red and appears to cycle regularly from -2 to +2 over the course of five years. The number of Sea Lion Pups born is graphed in blue and appears to be the opposite of the El Niño intensity for that year. The number of pups born is rising from 1975 (11,000) to 2011 (61,000) with ups and downs along the way; most notably in about 1998 when the number of pups born was only about 12,000 and the intensity of the El Niño was particularly high at +2.

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Figure 7.19. Conceptual Flow of Instructional Segments in Example High School Chemistry in the Earth System Course

This diagram shows links between the instructional segments in the Chemistry in the Earth course. Combustion is linked to Heat, Climate Change, and Ocean Acidification. Heat is linked to Plate tectonics (convection), and Atoms and Elements (particles). Atoms and Elements is linked to Chemical Reactions (Bonds). Chemical Reactions is linked to Climate Change (Fossil Fuel Combustion) and Equilibrium. Equilibrium is linked to Ocean Acidification (CO₂ in Atmosphere/Ocean).

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Figure 7.20. Heat-Flow Simulation

A screenshot of an interactive simulation. At the top of the image are three small round dots: red, yellow, and green. Also at the top: Energy2D V2.3:/Users/dalessio/FoodCalorimetry.e2d. On the next line are the control icons: an arrow, a square, a circle, a capital I, a freeform closed figure, a white dot with an arrow coming out of it, a dropdown menu arrow, a thermometer, another dropdown menu arrow, a graph icon, a dotted circle that appears to be selected, a magnifying glass with a plus symbol inside, and a partial view of a magnifying glass with a minus symbol inside. On the left side of the image is a measuring device marked from zero to nine with an “m” where the 10 would go. The same measuring tool is along the bottom of the image in a black band. At the bottom of the image is the “Ground” and what appears to be the logo Energy2D. The image is labeled “soda can.” There appears to be water inside. There is a thermometer halfway in the water that reads 19.4 degrees Celsius and one at the bottom of the water that reads 22.7 degrees Celsius and is labeled T1. Also labeled Water Flow 1 is a prop icon. Just outside the soda can next to the top of the can is a thermometer that reads 18.6 degrees Celsius, There is another thermometer just outside the bottom of the can that reads 28.9 degrees Celsius. There appears to be a heat source heating the soda can from the bottom with a thermometer next to that reading 24.1 degrees Celsius and labeled T2. There is another prop icon labeled Air Flow 1 just above the heat source.

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Figure 7.22. Seafloor Age

Outline map of the world showing the boundaries of the tectonic plates. Arrows indicate the direction and velocity of the movement of the plates—a longer arrow indicates a greater velocity. The plate boundaries are color-coded to indicate whether the boundary is convergent, transform, or divergent. The scale of the map is five millimeters equals 1,000 kilometers. The scale of the arrows is one centimeter equals 50 millimeters per year. The west coast of North America has many arrows pointing northwest. Much of the coast of California is a transform boundary.

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Figure 7.22. Seafloor Age

This is a world map showing the age of the seafloor using color-coding. This map shows newer rock forms along the plate boundaries. The world map is marked with latitude in degrees every 30 degrees both North and South.  The continents are white. The age of the seafloor color key is at the bottom of the image; the key is titled Age of seafloor (millions of years), The key ranges from zero on the left to 280 million years on the right. The colors follow the order of color wavelength: red, orange, yellow, green, blue, and purple. Red indicates the newest seafloor and purple the oldest. This map indicates the seafloor along the west coast of North America is young (red), and the east coast of North America is older (purple).

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Figure 7.23. Patterns in the First Ionization Energy of Different Elements

This is a graph titled First Ionization Energies. The y-axis is labeled Ionization energy (kJ/mol) and ranges from zero to 2500 in increments of 500. The x-axis is unlabeled but is the atomic number of each element and ranges from zero to 50 in increments of 10. Not every element in each period is identified. On the left are Hydrogen (1, 1400) and Helium (2, 2400). Helium is noted as a Noble gas. The second period ranges from Lithium (3, 550) to Neon (10, 2080). The third period ranges from Sodium (11, 495.7) to Argon (18, 1520). The fourth period (containing transition elements) ranges from Potassium (19, 418.6) to Krypton (36, 1351). The fifth period (also containing transition elements) ranges from Rubidium (37, 402.9) to Xenon (54, 1170). Each period begins at the bottom with an alkali metal and ends at the top with a noble gas.

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Figure 7.24. Models of Atomic Structure Explain Periodic Trends

Bohr model and octet rule illustration: Na is a sodium atom. Thesodiumnucleus contains 11 protons and 12 neutrons. Surrounding the nucleus are three circular shells containing 11 electrons (two, eight, and one). CI is a Chlorine atom. Thechlorinenucleus contains 17 protons and 18 neutrons. Surrounding the nucleus are three circular shells containing 17 electrons (two, eight, and seven). Na+ is a Sodium ion (a cation); Cl- is a Chloride ion (an anion). When combined they form NaCl with the outermost electron from the Na atom joining the Cl atom.

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Figure 7.25. Patterns and the Periodic Table

This diagram shows patterns in the table of elements. Atomic radius is represented by a blue arrow pointing from top to bottom and from right to left. Electron Affinity is represented by a brown arrow pointing from left to right and from bottom to top. Ionization Energy is represented by a yellow arrow pointing left to right and bottom to top. Nonmetallic character is represented by a green arrow pointing diagonally from the lower left to the upper right. Metallic Character is represented by a gray arrow pointing diagonally from the upper right to the lower left.

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Figure 7.26. Covalent, Polar Covalent, and Ionic Bonding

Illustrations of three types of bonds, nonpolar covalent, polar covalent, and ionic.

1. Nonpolar covalent bond (CI to CI): Bonding electrons shared equally between two atoms. No charges on atoms.
2. Polar covalent bond (slight+ (H to CI) slight-): Bonding electrons shared unequally between two atoms. Partial charges on atoms.
3. Ionic bond (Na+ to CI-): Complete transfer of one or more valence electrons. Full charges on resulting ions.

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Figure 7.27. Models of Energy Changes in Chemical Reactions

Six subpanels with different models of energy changes in chemical reactions. Panel a) shows a red box labeled Chemical System with arrows pointing outward. Panel b) is similar to a), except that the box is blue and the arrows all point inward to the Chemical System box. Panel c) shows a graph of Gibbs free energy versus time with Reactants on the left and Products on the right. As time progresses, the Gibbs free energy goes gently upwards and then falls back down again to a lower value than before. The left side of the graph is labeled reactants and the right side is labeled products. Panel d) is similar to Panel c) except that the curve is a mirror image of c) but still has Reactants on the left and Products on the right. It starts off lower, goes way up, and then comes back down to a value higher than the starting point. Panel e) depicts molecules as balls. An upward pointing arrow on the left indicates that the position of the molecules in the figure is related to their enthalpy. There are three molecules at the start. In the middle of the panel, all the molecules are broken apart into nine individual atoms (shown as separate balls). These broken apart balls are higher up in the figure and an arrow pointing upward says 'breaking bonds.' On the right side of the panel, there are three molecules again, but they are different than the starting point and are located much lower on the page (indicating a drop in enthalpy). A red arrow points downward with the label ‘forming bonds’. Panel F is similar to Panel E except that there is no arrow indicating enthalpy. Instead, the molecules are in one box, an arrow (with energy given off) labeled 'bonds break' points to the next box of individual atoms, and then a second arrow points to a box with the three new molecules with the label ‘bonds form’. A yellow explosion symbol with the label 'energy' appears at the bottom, indicating energy is given off.

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Figure 7.28. Developmental Progression of Models of Energy in Chemical Reactions

Middle School example:

• Photosynthesis: 6 CO₂ + 6 H₂O + energy in goes to C₆H₁₂O₆ + 6 O₂
• Aerobic Respiration: C₆H₁₂O₆ + 6 O₂ goes to 6 CO₂ + 6 H₂O + energy out.
• The glucose (C₆H₁₂O₆) molecule is highlighted in each equation.
• Introductory High School example
• Photosynthesis is written in a right-facing arrow; Aerobic respiration is written in a left-facing arrow.
• There is a graph with bond energy on the y-axis and progress of reaction on the x-axis.
• The line of the graph shows C₆H₁₂O₆ + 6 O₂ on a flat part of the graph; the graph goes sharply upward and then sharply down. At the end of the graph where it levels out, we have 6 CO₂ + 6 H₂O.

In the next panel is the Advanced High School example. This has the same graph as introductory high school, but the line of the graph shows many interactions of the reactions with the text "series of intermediate reactions with smaller activation energy enabled by enzymes."

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Figure 7.29. Relationship Between Global Population and Atmospheric CO₂

Double-line graph shows concentration of CO₂ in atmosphere (ppm) in a blue line from years 1850 to 2030. Brown line shows global population (billions). The lines coincide, as the population rises, as the concentration of CO₂ rises. There is a sharp rise in both measures after 1950.

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Figure 7.30. Energy Flows in the Earth System

The Earth System is represented by a large rectangle at the bottom of the image with the Earth’s surface at the top of that box. The Sun is represented by a yellow circle above the Earth and outer space is represented by a grey box also above the Earth. From the Sun, there are arrows pointing to Earth and then reflected back to outer space. “Visible light and short wave infrared (IR) from the Sun radiates to planet Earth.” Along the reflection arrow, “About one third of sunlight does not heat the Earth system.” On the surface of the Earth with a red arrow pointing up, “Earth’s surface heats the atmosphere by conduction and by radiating long-wave infrared that is absorbed by greenhouse gases.” Also, on the surface of the Earth with a red arrow pointing both up and down: “Greenhouse gases radiate long-wave infrared within atmosphere, back to surface, and to outer space.” There is a long red arrow pointing to outer space: “Some long-wavelength IR radiates to outer space without being absorbed in atmosphere.” Just under the surface of the Earth is a double-headed horizontal arrow: “Winds and ocean currents move heat energy within the Earth system from equatorial regions toward the poles.” At the bottom of the image: ”Most of the absorption of light energy happens at Earth’s surface. Absorbed light energy is transferred to heat energy. Areas nearer to the equator absorb much more sunlight and are much warmer than areas nearer the poles.”

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Figure 7.31. A Reinforcing Feedback in Earth’s Climate

An upward spiral changing in color from grey at the bottom to red to black at the top. Noted on the diagram: Temperature increases (one up arrow) leads to Melting Ice (one up arrow), which leads to Absorption of Sunlight (one up arrow), which leads to increase in Temperature (two up arrows), which leads to Melting Ice (two up arrows), which leads to Absorption of Sunlight (two up arrows), which leads to increase in Temperature (three up arrows), which leads to Melting Ice (three up arrows), which leads to Absorption of Sunlight (three up arrows), which leads to increase in Temperature (four up arrows).

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Figure 7.32. A Counterbalancing Feedback in Earth’s Climate System

Beginning at the bottom left: Temperature increase leads to Fusion increase, which leads to Star expands, which leads to Temperature decrease, which leads to Fusion decrease, which leads to Star contracts (Gravity), which leads to Temperature increase, and around again.

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Figure 7.33. Temperature and Carbon Dioxide Over the Last 800,000 Years

Information from ice core records of temperature and CO₂ concentration are graphed together. The measurements of temperature and carbon dioxide appear to follow the same pattern of increase and decrease over the last 800,000 years until the present day when the concentration of CO₂ rises to 400 ppm; in the past the high concentration only reached 300 ppm.

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Figure 7.34. Time Series of CO₂ on a Classroom Wall

Photograph of poster paper taped across a wall showing years 2005, 2006, 2007, 2008...with dotted graphs showing trends of C0₂ levels throughout a calendar year. A pattern emerges showing higher concentrations of CO₂ in the summer months than in the winter months.

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Figure 7.35. Two Representations of the Same Data Set by Different Sources

Two graphs are shown. On the left is a graph from a newspaper (The Weekly Star [fictitious]). The title is Graph showing tenths of a degree above and below 14C world average. The y-axis is marked from zero to .9 in increments of .1. The x-axis is marked in years from 1997 to 2012. The graph has many ups and downs but overall remains horizontal. The author highlights 1997 at .5 degrees Celsius and 2012 also at .5 degrees Celsius. The graph on the right compiled by NASA’s Earth Observatory shows data from four different sources: NASA Goddard Institute for Space Studies, Met Office Hadley Centre/Climatic Research Unit, NOAA National Climatic Data Center, and Japanese Meteorological Agency. All four lines of data coincide very closely. The y-axis is labeled Temperature Anomaly (degrees Celsius) and ranges from -0.75 to +0.50 in increments of 0.25. The x-axis is marked in years from 1880 to 2000 in 20-year increments. This graph has many ups and downs but trends upward starting around 1980.

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Figure 7.36. Cause and Effect Chains Illustrate How Human Activities Affect Natural Systems

This is a diagram on global warming and climate change. Burning fossil fuels leads to more CO₂ in the atmosphere. This leads to more CO₂ in the Ocean, which leads to more hydrogen and ocean acidification. More CO₂ in the atmosphere also leads to Higher Air and Ocean Temperatures, which leads to sea level rise and changing rain patterns.

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Figure 7.37. What Fuels Provide the World’s Energy?

Line graph showing an increase in world energy consumption. The y-axis is labeled Energy, 1,000 TWh per year. It is marked in increments of five and is labeled from zero to 20. The x-axis is labeled Year and is marked in 10-year increments from 1970 to 2010. The types of energy used from most to least include: Oil, Coal, Natural Gas, Hydro, Nuclear, and Other Renewable.

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Figure 7.38. Le Châtelier’s Principle

Diagram showing how students should be able to apply Le Châtelier’s principle to predict ways to increase the product of a chemical reaction. For example, gas pressure is reduced and heat is given out when hydrogen and nitrogen combine to form ammonia. According to Le Châtelier’s principle, the reaction can proceed to produce more ammonia by increasing the pressure and/or by dropping the temperature. Conversely, more ammonia will decompose into hydrogen and nitrogen by lowering the pressure and/or raising the temperature.

Hydrogen molecules (white molecule) + nitrogen molecules (blue molecule).

Forward reaction increased by rise in pressure drop in temperature.

Backward reaction increased by lower pressure higher temperature.

Ammonia molecules (three white molecule bond to one blue).

Information across illustration in the middle "Nitrogen and hydrogen combine for ammonia. As they do so, the gas pressure is reduced and heat is given out.” According to Le Châtelier’s principle, to make the reaction proceed left to right, high pressures and low temperatures are needed.

Coming from the nitrogen molecules are two pressure gauges marked from zero to seven; the left one is marked four and the right one is marked two to show "gas pressure is reduced by combination of hydrogen and nitrogen molecule.”

Two thermometers from the nitrogen molecules; the left one shows a low temperature and the right one shows a higher temperature. Text reads: "combination reaction gives out heat."

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Figure 7.39. Pteropods

Two panels show photographs of four different Pteropods on top and three shells on bottom labelled from left to right A, B, and C showing the effects of "more acidic ocean water” with a red arrow going to the right.

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Figure 7.40. Chemical Interactions Between CO₂ and Water

Representation of CO₂ dissolving from the atmosphere into the ocean. There are a series of chemical equations. From top to bottom:

• CO₂ + H₂O two-way arrow H₂CO₃
• H₂CO₃ two-way arrow H⁺ + HCO₃-
• HCO₃- two-way arrow H+ + CO₃^2-
• Ca²⁺ + CO₃^2- two-way arrow CaCO₃ (drawing of a shell)
• Final equation is CO₂ + H₂0 + CaCO two-way arrow to Ca²⁺ + 2 H⁺ + CO₃-

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Figure 7.41. Simplified Equations for Carbonate Shell Chemical Reactions

Diagram "Carbonate reacting directly with CO₂ is not available for making shells in calcium carbonate" with the following information: CO₂ + H2O + CO3^2- two-way arrow 2 HCO₃-. The next line has equation CA²⁺ + CO₃^2- two-way arrow CaCO₃ (and a drawing of a shell at end).

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Figure 7.42. Four Interest Groups

Four boxes describe interest groups (Text reads: You should have at least one of each group, and duplicates as needed.) Interest Group One – Photosynthesizing organisms (organisms that take in CO₂ such as diatoms). Interest Group Two – Marine calcifying organisms (users of CO₂ and producers of CO₂ who make shells such as oysters, clams, coral, etc.). Interest Group Three – Low CO₂ Emitter (such as Island Nations, Fisheries, etc. that rely on healthy oceans and ecosystems). Interest Group Four – High CO₂ Emitters (such as industry giants, industrialized nations, etc. that rely on using and producing this type of energy).

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Figure 7.43. Conceptual Flow of Instructional Segments in Example High School Three-Course Model Physics of the Universe

A flow chart of instructional segments and how they relate to one another in the three-course model course: Physics in the Universe. 

Forces and motion leads to Forces at a distance, which leads to Energy Conservation and Planetary Motion (includes gravity), which leads to Nuclear Processes and Origins of our Universe. Nuclear Processes leads to Energy Conservation (through fission), Radiometric dating (through decay), and Star Stuff (through fusion). Star Stuff leads back to Origins of our Universe (including spectra). Radiometric dating leads to Earthquake waves (through seafloor age evidence of plate tectonics). Earthquake waves leads to Electromagnetic spectrum (through wave propagation).

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Figure 7.44. Collisions Occur in a Variety of Contexts

Mountains and car crashes involve collisions whose movement and forces can be modeled in computer simulations (bottom).

This is a picture of two different types of collisions. On the left is a picture of a mountain; just below it is a computer simulation of the forces that created the mountain. On the right is a picture of a car being crash tested by crashing it into a wall. Just below is the computer simulation of the forces that deformed the car.

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Figure 7.45. Physical Model of Forces Deforming Layers in a Sandbox

Two panels show before and after pictures of a box of sand with distinct layers of differently colored sand being squeezed together when the sides of the box are moved toward one another. It shows the layers are pushed up and resemble a mountain in the after picture.

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Figure 7.46. Computer Model of Layers Deforming During Continental Collision

Computer model of the layers of material as continental plates collide. The layers are being compressed and a mountain is being formed. At the top of the image is a right-pointing arrow that reads “total shortening 192 km.” There is a scale on the lower left corner that shows the entire model, top to bottom, measures 50 km and horizontally about one inch in the model represents 50 km. The entire image is about five and a half inches long. The top of the image is sectioned into four parts labeled from left to right: pro-basin, pro-wedge, retro wedge, and retro basin. About the middle of the image at the bottom is a label “S” with an arrow curving down and to the right. On the left is the note “left half of model moves toward S: ‘lower plate’”. On the right is the note “right half of model is stationary: ‘upper plate’.”

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Figure 7.47. Example Student Diagrams

Two examples of student work. Student one has represented the sand with the force of the crank on the right side and pointing right and the force of gravity from the middle of the sand pointing down. Student two has represented the sand with “stuff to the left” on the left side pointing right and toward the sand. “Stuff above” is above the sand and pointing down toward the sand. “Stuff to the right” on the right side of the sand and pointing to the sand on the left. The force of gravity from the middle of the sand pointing down. “Friction” is noted on the lower left corner of the sand and pointing both to the left and down. “Stuff below” is below the sand and pointing up toward the sand. In the background is a large block arrow pointing to the upper right corner with the note “overall motion.”

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Figure 7.48. Engineering Solutions to an Egg Drop Challenge

A series of six photographs depicting student-designed vehicles to keep an egg from breaking in a fall. The upper left shows an egg encased in a plastic bag with packing 'peanuts.' The top middle shows a cup suspended in a frame of straws. The upper right is similar except that it uses popsicle sticks for the frame. The lower left is a cardboard box with balloons attached to the top. The bottom middle has a balloon with plastic bags taped to it. The bottom right includes more balloons surrounding a plastic bag with packing peanuts.

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Figure 7.49. Real World Engineering Applications of Momentum-Impulse Connections

A series of five illustrations: (a) an automobile air bag; (b) an automobile passenger compartment with crumple zones in the front and rear; (c) a cross section of a helmet with various layers labeled: Rigid outer shell; face shield; comfort/fit padding on the interior; and the impact-absorbing liner; (d) a baseball catcher’s mitt; (e) a parachute.

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Figure 7.50. Many Physical Processes Follow the Inverse Square Law

This is a-four column table. The first column lists the phenomenon, the second is titled 1r, the third 2r, and the fourth 3r. The first row: radiation; 1r: I_radiation = S over 4 Pi r squared; 2r: I_radiation = S over 16 Pi r squared; 3r: I_radiation = S over 36 Pi r squared. The second row: sound: 1r: I_sound = P over 4 Pi r squared; 2r: I_sound = P over 16 Pi r squared; 3r:  I_sound = P over 36 Pi r squared; The third row: illumination: 1r: E = I over 4 Pi r squared; 2r: E = I over 16 Pi r squared; 3r: E = I over 36 Pi r squared; The fourth row: electrostatics. 1r: F_e = k times the quantity Q₁ times Q₂ over r squared_;  2r: F_e = k times the quantity Q₁ times Q₂ over 4 r squared_; 3r: F_e = k times the quantity Q₁ times Q₂ over 9 r squared_;  The fifth row: gravity. 1r: F_e = k times the quantity m₁ times m₂ over r squared_;  2r: F_e = k times the quantity m₁ times m₂ over 4 r squared_; 3r: F_e = k times the quantity m₁ times m₂ over 9 r squared_. Under this table is a three-dimensional perspective drawing of area increasing proportionally to the distance from an object: at one radius the area of a square is one square unit; at two radii the area is four square units; and at three radii the area is nine square units.

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Figure 7.51. Schematic of a Power Plant

Schematic diagram shows how a power plant works by using pulverized coal in a boiler to heat the water (which also produces combustion gases in the stack), the water turns to steam, the steam turns the turbine, and the turbine then turns the generator thereby creating electricity.

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Figure 7.52. Magnetic Fields and Electric Currents

Five illustrations in two rows. The first row is titled Flowing Current Induces a Magnetic Field figure (a) Øersted’s experiment illustrates that an electric current generates a magnetic field; (b) a compass wrapped in wire through which an electric current flows; and (c) a circle of six compasses surrounding a wire carrying electric current, and the wire is perpendicular to the plane the compasses are on. The second row is titled Magnet moving relative to a wire induces a current. Figure (d) shows a horseshoe magnet with a wire across its poles. The wire is attached to a galvanometer with its needle pinned to the right side. A person’s hand is moving the wire through the magnetic field. And (e) a bar magnet with wire wrapped around the north pole, attached to a galvanometer with its needle pinned to the right side. The magnet is moving in and out of the loops of wire.

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Figure 7.53. Models of Nuclear Processes in Atoms

Two panels are presented. On the left, a drawing of fission on top and fusion on the bottom. In the fission drawing, a neutron comes towards a large nucleus of uranium-235 (indicated by lots of red and grey spheres clumped together). The nucleus breaks into two pieces, barium-139 and krypton-95 while two neutrons fly away. A big orange crashing icon indicates that energy is released. In the fusion diagram, a hydrogen and deuterium atom meet to temporarily form a large unstable nucleus that releases a huge amount of energy as a helium nucleus and a neutron continue. On the right, a drawing of alpha decay on the top and beta decay on the bottom. In alpha decay, a large unstable nucleus (indicated by a clump of lots of red and grey spheres) decays into a smaller, more stable nucleus and gives off a helium atom (also called an 'alpha particle,' indicated by two red spheres and two grey spheres clumped together). In beta decay, there are two options. On the top, a smaller clump of red and grey spheres indicating a carbon-14 nucleus decays via beta-minus into a very similar nucleus labeled nitrogen-14. The only difference is that one red sphere is now grey. An anti-neutrino and electron also get released (indicated by small spheres). In beta-plus decay, a carbon-10 nucleus changes into a boron-10 nucleus. Again, the clumps are very similar except that one of the grey spheres has changed into a positive red sphere. A small neutrino and positron also get released.

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Figure 7.54. Rock Ages in the Continental US and Seafloor

Two color-coded maps. On the top is a map of the United States titled Age of Continental Rocks in millions of years. The key ranges from zero on the left to 4,000 million years on the right and is uneven in terms of representation. Zero to 65 million years is as long as 440 to 4,000 million years. The eastern half of the United States appears to be much older than the western half. The oldest parts of the lower 48 states appears to be in the northern region around Michigan and Minnesota. The youngest parts appear to be in the Rocky Mountains.

On the bottom is a world map showing the age of the seafloor using color-coding. This map shows newer rock forms along the plate boundaries.  The world map is marked with latitude in degrees every 30 degrees both North and South. The continents are white. The age of the seafloor color key is at the bottom of the image; the key is titled Age of seafloor (millions of years), The key ranges from zero on the left to 280 million years on the right. The colors follow the order of color wavelength: red, orange, yellow, green, blue, and purple. Red indicates the newest seafloor and purple the oldest. This map indicates the seafloor along the west coast of North America is young (red), and the East coast of North America is older (purple).

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Figure 7.55. Seismic Tomography Reveals Evidence of Plate Tectonics

A color-coded cross section of the Earth that includes about one-fourth of the United States from the Rockies to the Great Lakes to the Atlantic Ocean. The color-coding key is at the bottom of the diagram indicating Seismic wave speed. From left to right the key is marked Slower to Faster and the colors range from red on the left to orange to yellow in the middle to aqua to dark blue on the right. There are three distinct layers with depth marked on the side of the diagram ranging from zero at the surface to 3,500 km where Earth’s core begins. The first layer is about 400 km deep and shows where earthquakes are located. The next layer is about 300 km deep and includes parts where seismic waves travel fast and some parts where they travel slowly. The third layer (Earth’s mantle) extends from 700 km to 3,500 km deep. The notes in the interior of Earth’s layers: Subducted plate points to an area labeled fast. Example paths of seismic waves shows curved lines emanating from a focal point of an earthquake and coming out on Earth’s surface in three different spots fairly far away from the origin.

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Figure 7.56. Video Clip of a Person Experiencing an Earthquake

This is a series of five frames from a video. There is a man eating lunch and feels mild shaking and looks up at 0:04 seconds. Next at the 12-second mark people in the office recognizing the shaking as an earthquake. They race to leave the room. At the 15-second mark strong shaking begins; there are no people in the frame. At the 25-second mark peak shaking occurs; no people in the frame (note: S-waves are stronger). At the 50-second mark the earthquake is over.

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Figure 7.57. Measurements of an Earthquake from Different Locations

This is a seismograph demonstration: the x-axis is labeled seconds and ranges from zero to 60 in ten-second increments. The y-axis shows shaking velocity downwards and upwards. It provides three locations and all locations recorded two pulses of shaking but at different times and with different velocities.

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Figure 7.58. The Tortoise and the Hare Analogy for Two Waves Traveling at Different Speeds

Illustration that shows a race between a tortoise and a hare at four different time intervals. The graph plots time versus distance for each character. At zero seconds they are together at the starting line, and at one second they have both moved forward but the hare is ahead. At two seconds the hare is farther ahead, and at three seconds the hare is finishing the race and the tortoise is only halfway done.

"The longer distance the race, the longer the time between when the hare and tortoise finish."

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Figure 7.59. Physical Model of Different Height Buildings in a City

Five rectangles of paper are attached to two pieces of wood. The rectangles are of graduated height and labeled with letters A (shortest) through E (tallest). Each rectangle has a binder clip attached to the top. This model is meant to illustrate city buildings in an earthquake.

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Figure 7.60. Computer Model of Waves Traveling Through Materials with Different Velocities

This is showing a simulation of how waves travel through different materials. The source of the wave is shown in the upper left of the screenshot with waves radiating outward. Waves travel at different velocities depending on the material they are traveling through. Velocity equals frequency multiplied by wavelength. The simulation settings adjustments are shown in the upper right of the screenshot where students can adjust settings. The material the wave is traveling through are color-coded. Waves travel faster through the reddish material and slower through the green-blue material. There is a note on the diagram that reads “Waves arriving here travel through both materials. The time it takes waves to get here therefore depends on the velocity of both materials.”

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Figure 7.61. Chart of the Electromagnetic Spectrum

Shows the bands of the spectrum with familiar objects for size reference. There are four parallel number lines. The first one is labeled wavelength lambda (m) and ranges from 10 to the third power (the size of a football field on the left to 10 to the negative 12 to the size of subatomic particles on the right. The second number line is labeled wavenumber (cm to the negative one). The ranges are from 10 to the negative five on the left to 10 to the 10 on the right. The third number line is labeled electron volt (eV). It ranges from 10 to the negative nine on the left to 10 to the six on the right. The fourth number line is labeled frequency (Hz). It ranges from 10 to the five on the left to 10 to the 21 on the right. For size reference, there are pictures of familiar items across the top of the four number lines. In order from left to right they are a football field, man's height, baseball, paperclip thickness, paper thickness, cells, bacteria, viruses, water molecule, atom, and subatomic particles. Under the four number lines are the bands of the spectrum from left to right: they are Radio spectrum including Broadcast and Wireless, Microwave, Terahertz, and Infrared (including far IR, Mid IR, Near IR). Visible wavelengths (nm) shows the spectrum of color ROYGBIV, Ultraviolet (including Near UV and Extreme UV), X-Ray (Soft X-ray and Hard X-ray), and Gamma. Under these bands are more pictures of familiar objects that utilize the particular wavelength including from left to right: radio, sound waves, ultrasound, TV, microwave, wireless router, radar, airport screening, fiber telecom, mobile phone, remote control, night vision, visible light, dental curing, suntan, baggage screen, medical x-ray, crystallography, PET imaging, and cosmic ray observations.

At the bottom of the images appears lambda = 3 times 10 to the 8/frequency = 1/(wn*100) = 1.24 times 10 to the negative 6/eV.

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Figure 7.62. Color Spectrum of Our Sun

This is a graph of the intensity of light at each wavelength. The y-axis is labeled Spectral Irradiance (W/m²/nm) and ranges from zero to two in one-unit increments. The x-axis is labeled Wavelength (nm) and ranges from 400 to 700 in 100-unit increments. The height of each color indicates the intensity of light at that wavelength. The highest intensity is at about 490 nm and the lowest is at about 350 nm.

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Figure 7.63. Spectra of Six Different Stars

Chart shows data from the Sloan Digital Sky Survey. Power density (log scale)[no markers or units] is on the y-axis and wavelength is on the x-axis from 400 to 900 nm. The spectra of six stars are shown. On the highest line, hydrogen is identified in four different places; this identification appears in the top three lines. In the bottom three lines, magnesium (520 nm), sodium (590 nm), and calcium (880 nm) are identified along the spectrum. All six lines converge at about 900 nm.

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Figure 7.64. A Model of Absorption Lines

Information on top of diagram: "Light energy to less light energy to energy re-emitted in a different direction and/or at a different wavelength as electron returns to ground states."

This information at bottom of diagram: "Potential energy as excited electron occupies a higher energy orbital."

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Figure 7.65. A Counterbalancing Feedback in the Stars

Beginning at the bottom left: Temperature increase leads to Fusion increase, which leads to Star expands, which leads to Temperature decrease, which leads to Fusion decrease, which leads to Star contracts (Gravity), which leads to Temperature increase, and around again.

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Figure 7.66. How Does Star Brightness Depend on Temperature?

Hertzsprung-Russell Diagram: Absolute Magnitude on the y-axis, ranging from zero at the top of the diagram to 30 at the x-axis in five-unit increments. Temperature is on the x-axis ranging from 10,000 on the left to zero on the right. The Hertzsprung–Russell diagram, is a scatterplot of stars showing the relationship between the stars' absolute magnitudes or luminosities versus their spectral classifications or effective temperatures. In general the higher the magnitude the lower the temperature.

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Figure 7.67. Energy Transfer from the Sun to the Earth

A diagram of the sun in yellow (red circle is the core, fusion) emitting radiation (Orange layer around the core). Another layer of the Sun is yellow where convection is shown and labeled Envelope. The Visible surface is a thin line around the yellow layer. Outside of the surface is the atmosphere where squiggly lines show radiation emanating from the Sun toward Earth. These lines are labeled Thermal Radiation (black body). Just outside the atmosphere is labeled Spectral Absorption.

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Figure 7.68. Evidence for the Big Bang

Three images comprise the figure. The first in the upper left is titled Redshift versus Distance of Stellar Spectra. This is a dot graph; on the y-axis is speed (km/s), it ranges from zero to 40,000 units in 10,000-unit increments; and on the x-axis is the Distance from Earth in Millions of Light Years, ranging from zero to 150 in 30-unit increments. Three stars are chosen and their spectra are shown, and as the stars get farther from earth the spectra shift a bit to the right. The second image in the upper right is titled Relative abundance of different elements. This is a line graph: the y-axis is labeled Relative abundance (percent of Sun's mass, log scale) (ranges from 10 to the negative eight to 75 percent), the x-axis is labeled Atomic number (ranges from zero to 80 in 20-unit increments). Hydrogen is labeled as 75 percent, Helium at 23 percent, Beryllium at 10 to the negative eight percent, and Iron at about 0.5 percent. The third image is titled Cosmic Microwave Background, Tiny variations in the temperature of the early universe in different regions of the sky. The temperature of the early sky is depicted with color-coding ranging from dark blue at -0.0002 K to dark red at +0.0002 K. The average is labeled at 2.2725 K and is light blue-green.

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