Unit 5 Study Guide BIO 111

Select all of the following that lower an individual's carbon footprint

- Heating through passive solar and geothermal energy - Carpooling or taking public transportation

Carbon footprints

- Mode of transportation (car vs bus or bike), The source of energy used in ones home (coal vs solar), The amount of energy used in one's home, Diet, especially the amount of beef and dairy consumed

Photosynthesis and the carbon cycle

CO2 + H2O < Reaction in All Living Organisms (Cellular Respiration) = Reaction in Plants (Photosynthesis) > O2 + C6H12O6

Impacts of climate change

- Diseases that were historically tropical are beginning to spread - Severity of drought and heat waves has increased - Habitat loss has increased - Frequency of drought and heat waves has increased - Reptiles, amphibians, and plants are going extinct at increased rates

Greenhouse Gases in the Atmosphere

- Greenhouse gases, such as carbon dioxide, water vapor, and methane, retain heat near the surface of the planet. - Although many factors may contribute to climate change, perhaps the most significant influence comes from several gases in our atmosphere. Collectively called the greenhouse gases, these compounds trap heat near the Earth's surface. Several greenhouse gases, such as water vapor, are normally present in the atmosphere, and play an important role in maintaining the climate of the planet within a range that supports life.

What Is Photosynthesis?

- With just a few exceptions, the energy that life on this planet uses, whether in the form of food, wood, or fossil fuels, has its origins with photosynthetic organisms, such as the tree. - These organisms are autotrophs, meaning they are organisms that make their own food. - By using the energy from sunlight, water, and carbon dioxide from the atmosphere, a plant is able to make carbohydrates through photosynthesis.

biome

A large-scale community of organisms, primarily defined on land by the dominant plant types that exist in geographic regions of the planet with similar climatic conditions

Relationship between Climate Change and Global Warming

A number of weather events, such as extreme precipitation and heat waves, are correlated with climate change, while for others (such as tornadoes), the connections are still being investigated.

invasive species

An invasive species is one that has been introduced into places outside its natural range, usually through human actions—an introduction that often negatively impacts the biodiversity, community structure, and functioning ecosystem of the native area. As humans migrate around the globe, they sometimes unintentionally bring with them plants, animals, and other organisms.

As climate change continues, the prevalence of vector-borne disease has increased. Why is this?

As climates have warmed and winters have become less severe, the range of mosquitos and ticks has increased, bringing with them the diseases they carry.

Altering Weather Patterns in the US

Climate change is causing some areas of the United States to be drier (west and southeast), while other regions are experiencing increased precipitation (central and northeast).

Chlorofluorocarbons (CFCs)

Compounds used in refrigerants and to make spray propellants

Climate change and biomes

Coral bleaching is leading to the destruction of coral reef ecosystems worldwide

Ozone

Natural processes and the interaction of solar energy with pollutants in the lower atmosphere

Ecological Levels

Smallest to largest - Species, population, community, ecosystem, biosphere

Properties of Light

Solar energy strikes the planet as particles (photons) traveling at different wavelengths. There are a wide range of wavelengths, including infrared (heat) and X-rays, but the wavelengths that are most important to photosynthesis coincide with the visible spectrum of light.

Biosphere

The sum of the locations where life exists on Earth

What Are Fossil Fuels?

Today, fossil fuels still account for over 80% of the United States' energy needs. This number is not decreasing. Despite the development of alternative energy sources. - Fossil fuels include oil, coal, and natural gas.

Which of the following groups is suspected of causing climate change?

fossil fuel usage, deforestation, and agriculture

Difference between Climate Change and Global Warming

- The term global warming was one of the first used by the scientists who discovered the upward trend in temperatures in the 1980s. - The term is often still used interchangeably with climate change. However, they are not exactly the same thing. Global warming is primarily associated with increases in the surface temperature. - We have defined climate as being the average weather patterns in an area over time, and that climate is often recorded as temperature and precipitation.

Light-dependent reactions and light-independent reactions

- Light-Dependent Reactions - Inputs include NADP+ and ADP, Requires solar energy, Must occur in the daytime - The Calvin Cycle - Requires high-energy carriers, requires chemical energy, can occur in daytime and nighttime, reduces carbon dioxide gas, produces carbohydrates

Savanna Biome

- Location: Africa, South America, and Northern Australia - Rainfall: 51-127cm - Temp: 24°C-29°C - Soil: Porous, clay - Plants: Grasses, Forbs, Scattered trees - Related Information: Extensive dry season and consequent fires. Well-developed root systems allow plants to quickly re-sprout after a fire

Climate change and aquatic ecosystems

- Coral reefs are composed of coral and algae that interact in a symbiotic relationship. - The algae are photosynthetic and provide coral with food in exchange for a habitat. - As higher water temperatures stress the coral, they expel their symbiotic hosts and die over time. - This is called coral bleaching and in addition to human activities, is leading to the loss of coral reef habitats. - It is expected that up to 90% of these reefs will be lost by the year 2050.

Photosynthesis and the Carbon Cycle

- Each leaf of a plant is a photosynthetic factory. Within the leaf are specialized cells, called mesophyll cells, that conduct the majority of photosynthesis. - The mesophyll cells contain structures called chloroplasts. Chloroplasts are a form of organelle (internal compartments) that are specialized for a specific type of chemical reaction—in this case, photosynthesis. - If you take a look at the chloroplast, you will notice some platelike structures called thylakoids. - Thylakoids are stacked into structures called grana, and the spaces between the grana is called the stroma. Each has a role to play in photosynthesis. - The thylakoids, and the surrounding area of stroma, is effectively a self-contained photosynthetic factory. There may be hundreds of thylakoids in a chloroplast, dozens of chloroplasts in a mesophyll cell, thousands of mesophyll cells in a leaf, and millions of leaves on a tree. Thus, a tree is actually a type of huge photosynthetic machine. - The inputs and outputs of photosynthesis and cellular respiration are connected by the carbon cycle. - The biosphere on our planet is dependent on this relationship. - The photosynthetic organisms (autotrophs such as plants) convert CO2 into carbohydrates, and then this food is used by both heterotrophs (those that eat others) and autotrophs to power cellular activities. - The CO2 is then cycled for reuse.

Evidence from Glaciers and Snow Covers of Climate Change

- Glaciers are dynamic and have natural cycles in which they expand and contract, depending on fluctuations in the local climate. However, since the 1970s, scientists have noticed that there has been a global loss of ice mass in glaciers. - Observations of glaciers around the world indicate that, with just a few exceptions, the extent of glacier coverage is decreasing. Some of the first evidence of global warming and global climate change was obtained from observations of glaciers. - Similar patterns are also being observed in the ice sheets covering both Antarctica and Greenland. Since 2002, ice sheets in both of these locations have lost ice coverage annually, and since 2009 that loss has accelerated rapidly. - Antarctica is estimated to be losing over 127 gigatonnes of ice per year, while Greenland is losing over 286 gigatonnes per year. A gigatonne is the equivalent of a billion metric tons, and in the case of water, a single gigatonne could fill over 400,000 Olympic-size swimming pools.

Desert Biome

- Location: Between 15° and 30° north and south latitude - Rainfall: 2-30 cm - Temp: 0°C-60°C - Soil: Dry - Plants: Cacti Plants with deep roots and reduced foliage - Related Information: Frequently located on lee side of mountain ranges, Little water vapor to prevent radiative cooling

Boreal Forests Biome

- Location: Between 50° and 60° north latitude - Rainfall: 40-100cm - Temp: Cold dry winters, short, cool, wet summers - Soil: Acidic, Nitrogen poor - Plants: Pine Spruce Fir - Related Information: Tree Layer, Ground Layer Needles decompose slowly returning fewer nutrients to the soil

Chaparral Biome

- Location: California, Mediterranean Sea, southern coast of Australia - Rainfall: 65-75 cm - Temp: 10°C-40°C - Soil: Ashes left after fire provide nitrogen - Plants: Shrubs - Related Information: Wet winters & dry summers Many plants produce seed that germinate only after a hot fire

Tropical Forest Biome

- Location: Equatorial Regions - Rainfall: 250-450cm - Temp: 20°C-34°C - Soil: Rainfall leaches nutrients from soil - Plants: Spreading roots and broad leaves - Related Information: Primary threat is logging Huge biodiversity Vertical layering: floor, understory, canopy,

Temperate Forests Biome

- Location: Mid-latitude regions - Rainfall: 75-150cm - Temp: -30°C to 30°C - Soil: Rich in organic and inorganic nutrients - Plants: Deciduous Trees - Related Information: Leaf litter protects soil from erosion and provides habitats for invertebrates and predators

Temperate Grassland Biome

- Location: Throughout central North America and Eurasia - Rainfall: 25.4- 88.9cm - Temp: Hot summers, cold winters, warm Spring/Fall - Soil: Fertile because of humus - Plants: Grasses - Related Information: Very few trees Maintained by fire and grazing

Why Is Carbon Important to Life?

- The ability of carbon to form bonds with four other elements means it can form long chains. - These carbon chains are often referred to as hydrocarbons, and the study of hydrocarbon chains in living organisms is called organic chemistry. - An organic molecule is one that contains both carbon and hydrogen.

The earth's climate and atmosphere

- The climate of a given area refers to its patterns of temperature and rainfall. - Other factors that impact climate include the amount of the sun's energy that strikes that area and its topography, or physical features. - The sum of all locations on earth where life exists is called its biosphere. - This area ranges from the depths of the oceans to the upper limits of the atmosphere, or the layers of gases that surround and protect the earth. - It is important to note that because the biosphere is dependent on climate, changes in the climate of one region may have great impacts on the climates of other regions.

How Does Climate Change Impact Disease?

- The distribution of species of Aedes mosquitoes, a vector for disease, has expanded in the United States due to milder winters and increased average annual temperatures. - Insects are one example of disease vectors, and the two most important forms of insect vectors are mosquitoes and ticks. Why these two? The life cycle of mosquitoes and ticks involves reproduction in warm areas, and access to the warm blood of their hosts. As they move between hosts, they have the ability to spread disease between individuals and species. - Aedes mosquitos are a vector for a number of human diseases, including Dengue fever, West Nile, Chikungunya, and Zika. As Aedes has increased its range in the United States, there has been a corresponding increase in the incidences of these diseases in these areas. Similar patterns are being seen in other insect species, such as Anopheles mosquitoes, which carry the parasite associated with malaria, and in tick-borne diseases, such as Lyme's disease.

Global warming

- The graph shows the land and ocean temperature anomalies for the Earth for the past several decades. - This means how far temperatures are from normal averages for given areas. - Notice that over time, there is a collective increase in the number of red bars, indicating that temperatures are warmer than normal. - In addition, these warmer than normal temperatures are increasing in their variation from the expected average temperature. - This phenomenon is known as global warming, or the increase in surface temperature of Earth.

What Is the Carbon Cycle?

- The major reservoirs for carbon are the oceans, underground in fossil fuels, and in the atmosphere. These reservoirs are also referred to as carbon sinks. - Within the biosphere, living organisms release carbon dioxide into the atmosphere through the process of cellular respiration during their breakdown of organic materials for energy known as a carbon source.

Evidence from Extreme Weather Events of Climate Change

- The severity of droughts, heat waves, and extreme precipitation events are all recognized to be influenced by an increase in global temperatures. For example, the average temperature in the United States has already increased by 1.2 °F (0.7 °C), with a projected increase of almost by 2.5 °F (1.4 °C) the year 2050. - Not all extreme weather events are the result of climate change. For example, while both hurricanes and tornadoes are known to be associated with local climate conditions, the scientific community is still assessing whether the observed patterns in the rates of these events can be contributed to global warming and climate change. - However, it is widely agreed among scientists that increases in land and ocean temperatures are contributing to the severity of hurricanes, with more category 4 and 5 storms occurring than normal patterns would suggest. Computer models indicate that, as the oceans warm in the next few decades, hurricanes will continue to increase in severity

What Is Carbon?

- The structure of a carbon atom is shown in the figure. Within the center of the element is the nucleus, which contains both protons and neutrons. - Protons are positively-charged, subatomic particles, and neutrons have a neutral charge. - In the periodic table the number above carbon is the atomic number, which represents the number of protons in an atom of carbon. - The number below the C is the atomic mass, which is the sum of the number of protons and neutrons in an atom of the element. - Carbon is an element, which means it cannot be broken down into smaller units by normal chemical processes. - An atom of carbon consists of 6 electrons in orbit around a nucleus containing 6 protons and 6 neutrons. - The number of protons is indicated above the elements symbol, and the weight of the atom (neutrons and protons) is indicated below the symbol. - The green circles are electrons: negatively-charged particles that have almost no mass. The number of electrons in an atom of an element is equal to the number of protons. In the case of carbon, there are six electrons. Notice that these electrons are located in circles, called electron shells. In reality, they are moving rapidly around the outside of the atom at different energy levels. - The electrons determine the chemical reactivity of an element. Generally speaking, the number of electrons in the outermost electron shell interact with atoms and other elements to form chemical bonds. The structure of carbon means that it prefers to form four chemical bonds at a time.

Evidence from the oceans of climate change

- When carbon dioxide enters the oceans, it produces carbonic acid, which leads to ocean acidification and negative impacts on shellfish. - Our planet is 71% water, and for that reason, we will first explore the evidence of climate change based on ocean observations. Carbon dioxide (CO2 ) dissolves very easily in water. As it does, it interacts with water (H2O) to form carbonic acid (H2CO3 ). The presence of carbonic acid in water increases the hydrogen ion (H+ ) concentration, which as a result increases the acidity of the aquatic environment. - The increase in acidity decreases the amount of carbonate (CO3 2- ) in the oceans. Carbonate plays an important role in the formation of shells of organisms such as crabs, lobsters, and clams. As the ocean acidifies, these organisms have a harder time forming shells and other hard structures. - The world's oceans act as a heat sink, or a temporary storage location for heat energy. Heat sinks are not unnatural. For example, they account for the moderate temperatures of Florida in the winter, but over longer time periods, they can influence the climate of surrounding land masses.

Nitrous Oxides

- released from agricultural practices like fertilizers and the burning of fossil fuels - considered a greenhouse gas - trap infrared heat and release it slowly back into the earth - considered a major contributing gas to the greenhouse effect

Water Vapor

- released from natural geological processes within the water cycle - trap infrared heat and release it slowly back into the earth - considered a greenhouse gas

The Molecules Involved in Photosynthesis

- ATP - Energy carrier of the cell. Conversion of ADP to ATP requires an input of energy. - NADPH - Carrier of high-energy electrons. Similar to the NADH used in cellular respiration. - CO2 - Source of carbon for the formation of carbohydrates. - H2O - Source of electrons for the light-dependent reactions. - O2 - Waste product of photosynthesis, released into the atmosphere. - CH2O - Output of photosynthesis, used to build carbohydrates (C6H12O6 ).

Carbon Dioxide

- Although (CO2 ) is found in very small concentrations in the atmosphere (parts per million), it is one of the most important of the greenhouse gases due to its ability to absorb infrared energy. - Carbon dioxide is produced through natural events, such as fires and volcanic activity. Our bodies produce carbon dioxide as a result of the breakdown of our food. Plants use carbon dioxide to produce carbohydrates, the basis of the majority of the food chains on the planet. - Increase of CO2 in the atmosphere is largely contributed by human activity

Methane

- Another important greenhouse gas is methane (CH4 ). Methane is a very rare gas in the atmosphere, with concentrations measured as parts per billion (ppb). - Methane is also relatively unstable, and once created, it only remains in the atmosphere for about a decade. - Still, methane is considered a very powerful greenhouse gas, with the ability to retain and release almost 30 times the amount of heat as CO2 .

Linking Carbon Dioxide and Global Temperatures

- A combined graph of global temperatures (colored bars) and atmospheric carbon dioxide concentrations indicates a direct relationship between the two observations. There is a direct relationship between atmospheric carbon dioxide concentrations and global temperatures. - Because human activity is the major contributing cause of elevated CO2 concentrations, climate scientists often use the term anthropogenic climate change to describe the human-climate relationship.

Vector

Something that moves an infectious agent (bacteria or virus) from one organism to another.

Climate change and the oceans

- As levels of carbon dioxide and other greenhouse gases rise in the atmosphere, global temperatures increase. - Sea levels increase as sea ice levels and glacier coverage decrease. - Carbon dioxide dissolves easily in water, forming carbonic acid - This causes the acidity, or pH of oceans to decrease. - This is called ocean acidification.

The greenhouse effect

- As solar energy strikes the earth, some is reflected back into space by areas of snow or ice. - However, some of this solar energy strikes areas of ocean or land where it is absorbed. - Once absorbed, it is released slowly back into the atmosphere as infrared energy, or heat. - Water, carbon dioxide, and other greenhouse gases trap some of this energy, allowing temperatures on earth to become warmer. - This phenomenon is called the greenhouse effect and is responsible for allowing our planet to be warm enough to sustain life.

Expected Changes in Biological Communities

- Biological communities represent complex interactions between species, and the changing climate across the globe, coupled with the threats of invasive species, is causing changes in the community structure of regions. - A terrestrial example are the woolly adelgids (Adelges tsugae), a small sap-sucking insect that is native to East Asia. In the United States, the woolly adelgid infects hemlock trees, causing the death of the tree in just a few years (Figure 3.7). Hemlocks grow in dense stands, which tend to keep the area under the trees cool and moist. Hemlock forests are home to a tremendous diversity of animals, including amphibians, newts, a variety of birds, and larger animals such as deer. - The increase in ocean temperatures worldwide is affecting a number of global ecosystems, also known as biomes. We can also see these changes in the structure of the communities that inhabit these biomes. For example, ocean acidification prevents shellfish from being able to calcify their shells. Because shellfish form an important part of the aquatic food web, their loss is reflected in a reduction in the overall community structure. - This acidification also reduces the amount of microscopic animals (zooplankton), which are an important part of the aquatic food chain, and thus can impact the health of fish populations, making them more susceptible to disease or reducing their ability to reproduce.

How Do Heat Waves and Droughts Impact Humans?

- Changes in precipitation patterns in the western United States have amplified the instances and severity of droughts, such as those currently being experienced in California. - In addition to the fact that these events disrupt agriculture production is the fact that more people die each year in the United States from heat waves (and related illnesses) than any other climate-associated factor. These events have a particular impact on the poor, elderly, and those with medical conditions. - One example is the California drought. The drought that spanned 2012 to 2016 contained the driest 4-year period in the state's history. Three years of this time span, 2014, 2015, and 2016, set records for the three warmest years in terms of statewide average temperatures. - Computer models suggest that the worst is yet to come. When predictions of the current levels of climate change are factored into the models, the data suggest there is an 80% chance that California, and the remainder of the southwest United States, may experience a "megadrought," which is an event lasting more than 35 years, before 2080.

Habitat Loss and Extinction

- Evolution is a powerful force in the biological world. In studying your local environment, you are witnessing the long-term adaptation of these species to the climate conditions of that region. - As conditions change over time, usually gradually, some species naturally go extinct, and others adapt to the changing environment. - These changes usually take place over relatively long periods of time, usually measured as thousands or millions of years. Climate change is occurring at such a rapid pace that species are not able to adapt to the changes fast enough.

Fossil fuels and climate change

- Fossil fuels are reservoirs of carbon, storing them deep in the ground. - When they are burned, this carbon is released back into the atmosphere, where it acts as a(n) greenhouse gas. - The emissions from fossil fuels have increased since 1995. - As a result, carbon dioxide levels have increased in concentration. - This is directly associated with increased global temperatures.

Climate change and extinction

- It is common for organisms to go extinct gradually as environments change - extinction is occurring at unprecedented rates, thought to be the result of human activities - As forest are bulldozed for livestock, the risk of extinction of the forest communities members increases - Amphibians and reptiles are at an increased risk of extinction because of their susceptibility to pollution in their ecosystems - As ocean acidification occurs, members of coral reef communities are at risk for extinction

Arctic Tundra Biome

- Location: Arctic regions in the Northern Hemisphere - Rainfall: 15-25 cm - Temp: -34°C to 37°C-52°C - Soil: Permafrost - Plants: Shrubs Grass Lichens - Related Information: 24 hours of daylight during growing season Bursts of productivity over summer

Evidence of climate change

- The map shown plots land and ocean temperature percentiles for March of 2018. - Areas plotted in red are warmer and normal and areas plotted in blue are cooler than normal. - Notice that overall, there are more red spots, indicating that most areas are warmer than normal. - This is especially true over oceans, as bodies of water have the ability to absorb heat, therefore acting like a heat sink. - Over long periods of time, these heat sinks have the ability to increase temperatures of nearby land masses, changing their climate.

What Is a Biome?

- The term ecosystem refers to a level of biological organization that represents the interaction of biological communities (the biotic factors) and abiotic factors, such as climate (temperature and precipitation). - Scientists often use the word biome to indicate the general characteristics of similar ecosystems across the globe. This includes the climate and the types of organisms living in that area.

Carbon Dioxide

- considered a major contributing gas to the greenhouse effect - Produced through natural events like fires and volcanoes, but also through the burning of fossil fuels - released from the decomposition of organic matter and from livestock and landfills - trap infrared heat and release it slowly back into the earth - considered a major contributing gas to the greenhouse effect

Methane

- considered a major contributing gas to the greenhouse effect - released from the decomposition of organic matter and from livestock and landfills - trap infrared heat and release it slowly back into the earth - considered a greenhouse gas

Desertification

Is another example of a biome level change that is associated with climate change. As we observed in our discussion of biomes, an increase in temperature and a decrease in precipitation leads to the formation of a desert biome. In addition to climate change, the deforestation of regions and poor agricultural practices (namely cattle farming) can lead to the conversion of grasslands to deserts.

Relationships within biological communities

Species in an area have evolved over long periods of time to interact together, in the process forming complex biological communities. Whereas some of these interactions are predator-prey interactions, others may be more cooperative (mutualistic). These interactions are often dictated by the physical characteristics of the ecosystem in which they live. These characteristics include the climate of the region.

Climate

The average weather patterns in a given area over time. Temperature and rainfall are the typical characteristics used to define climate. For example, in the spring, the climate of your area may be cool and rainy, while in the summer it could be hot and humid.

The Earth and Climate

The climate of a region is partially due to the amount of solar radiation striking the surface of the planet. Seasonal changes are due to the tilt of the Earth on its axis.

How Is Climate Change Altering Weather Patterns?

The impacts of global climate change can be observed right now, even in the United States. The temperature and precipitation data show that: - Average temperatures have increased between 1.2 and 1.8◦F over the past 50 years, with the majority of that change occurring since the start of the 21st century. The rate of regional heat waves is increasing across the country. - Average precipitation has increased by 4% in the past century. This has been very regional, with central and northeast areas experiencing increased precipitation, and areas in the west and southeast seeing reduced precipitation. The rate of extreme precipitation events, and droughts, is also increasing.

Light Reactions

The purpose of the light reactions is to capture the energy from the sun and transfer it to high-energy molecules. These reactions occur in the thylakoid of the chloroplast and use the photosynthetic pigments - The first set of reactions are called the light-dependent reactions because they require an input of solar energy. Here are the major events in this pathway: • The chlorophyll molecules absorbs energy from the sun. This energizes electrons (e- ) forming high-energy particles. • Water is broken down, releasing electrons, hydrogen ions (H+ ), and oxygen. The oxygen is a waste product and is released back into the atmosphere. • Some of the high-energy electrons are used to produce ATP from ADP + P. • NADP+ accepts some high-energy electrons to produce NADPH.

How Are Fossil Fuels Formed?

The term fossil fuels simply refers to a fuel source that has been formed within the Earth from plant and animal remains. There are several different forms of fossil fuels, such as oil, natural gas, coal, and shale, but the process by which each is formed is relatively similar. All involve submerging organic material (plants and animals) over long periods of time and subjecting them to the heat and pressure of the Earth's crust.

Calvin Cycle Reactions

These are the reactions that actually form the carbohydrate molecules from CO2 and the energy captured by the light reactions. Notice that some of the output from these reactions are recycled back to the light reactions. - The second set of reactions is called the Calvin cycle. It is also sometimes referred to as the light-independent reactions because they do not require sunlight. Here are the major events in this pathway: • CO2 is taken up by one of the molecules at the start of the cycle. This is commonly called carbon fixation, and it represents the method by which atmospheric carbon is taken up by plants. • ATP and NADPH from the light reactions is used to form more complex organic structures from the initial CO2 molecule. Once the energy is used, the resulting ADP and NADP+ are returned to the light-dependent reactions. • A molecule, called G3P, is created, which then forms CH2O and carbohydrates. • The pathway recycles its starting materials and prepares for the next input of CO2 .

Human society in its current form is unsustainable because

important natural resources are being consumed more quickly than they can be replenished.