Bioenergetics (Bio.A.3)

The Carbon Cycle The Carbon Cycle - the movement of carbon between the organisms, atmosphere, oceans, and soil. The exchange of carbon happens between living (biotic) and non-living (abiotic) things.

Abiotic Environments Carbon exists in abiotic environments as: Carbon dioxide (CO2) gas in atmosphere and in oceans Carbonate rocks (CaCO3) Examples: limestone and coral Fossil Fuels Example: coal, petroleum, and natural gas Dead organic material

Biotic Environments Plants take in carbon dioxide during photosynthesis to make food Phytoplankton – floating organisms that do photosynthesis Animals eat foods that contain carbon. Zooplankton – floating organisms that eat food containing carbon Remember… Autotrophs or producers are living things that make their own food (sugar). Hetertrophs or consumers are living things that must eat their food.

Once the carbon is in living organisms, it is further converted and released: Consumption - carbon transferred to a consumer when an organism is eaten Decomposition - carbon transferred to the soil via the decay of a dead organism Respiration - carbon released into the air as CO2 gas

Carbon Sinks Carbon Sink – a natural or manmade reservoir that holds and stores carbon for long periods of time Ex: Landfills, oceans, fossil fuels

Photosynthesis

Photosynthesis 6CO2 + 6H2O + sunlight → C6H12O6 + 6O2 (carbon dioxide) (water) (glucose) (oxygen) Photosynthesis converts light energy to chemical energy (glucose). Plants do photosynthesis to make food (glucose). Oxygen is a byproduct. From where do plants get carbon dioxide ? From where do plants get and water? Bio.A.3.2.1

Remember, autotrophs are producers that include: Plants Algae Some bacteria

Photosynthesis occurs in the chloroplasts (a type of plastid) Chloroplasts contain the green pigment chlorophyll. Chlorophyll is the pigment that uses sunlight to make food. It is made of protein. Bio.A.3.1.1

Green light is reflected so this is why most plants appear green. Most plants contain other pigments that help chlorophyll absorb more light. Example: carotenoids

Chloroplasts

Aerobic Respiration C6H12O6 + 6O2 → 6CO2 + 6H2O + 38ATP (glucose) (oxygen) (carbon dioxide) (water) (energy) Respiration converts the chemical energy of glucose to the chemical energy of ATP. Living things do respiration to make energy (ATP). Bio.A.3.2.1

Aerobic Respiration Occurs in ALL living things. C6H12O6 + 6O2 → 6CO2 + 6H2O + 38ATP (glucose) (oxygen) (carbon dioxide) (water) (energy) Occurs in ALL living things. CO2 and H2O are byproducts. Mostly occurs in the mitochondria of cells. Bio.A.3.2.1

ATP and Energy Bio.A.3.2.2

ATP Stand for Adenosine Triphosphate The “universal” energy Needed to run all processes necessary to support life such as thinking, running, breathing, etc. It is a chemical that contains 3 phosphate groups and is like a fully charged battery. ATP releases energy by breaking off phosphate (P). ATP ADP + P + ENERGY Bio.A.3.2.2

ADP is Adenosine Diphosphate. It is a chemical that contains 2 phosphate groups and is like a partially charged battery. ADP stores energy by adding a P. ATP ADP + P + ENERGY Bio.A.3.2.2

CELLULAR rESPIRATION There are two major types of cellular respiration: Aerobic respiration Uses oxygen Makes lots of energy (38 ATP) Occurs in mitochondria Anaerobic respiration (fermentation) No oxygen needed Makes a little energy (2ATP) Occurs in cytoplasm Two types: alcoholic and lactic acid Bio.A.3.1.1 Bio.A.3.2.1

Alcoholic Fermentation Glucose → alcohol + CO2 + 2ATP Ex: Yeast causes bread dough to rise when baked and alcohol evaporates. Bio.A.3.2.1

Lactic Acid Fermentation Glucose → Lactic acid + 2ATP Ex: Humans produce lactic acid in their muscles during rapid exercise (sprinting, weight lifting, etc.) Bio.A.3.2.1

Global Warming Global Warming

Greenhouse Effect Greenhouse effect – gases are creating a curtain around the Earth trapping sunlight in the atmosphere, which keeps the earth warm Greenhouse gases in the atmosphere include: Water vapor, carbon dioxide, methane, ozone, and nitrous oxide.

Global Carbon Output

Global Carbon Output

Global Warming Global warming – the gradual increase of greenhouse gases (especially carbon dioxide) increases the greenhouse effect, which increases the average global temperature

Connection Between CO2 concentration and Temperature Source: NOAA 2012

What does [CO2] look like today? Let’s take a closer look at this. Source: NOAA 2012

What about solar output? Source: NOAA 2012

Causes of Global Warming Human-caused activities have aided in global warming starting with the Industrial Revolution. Power plants 93% of emissions from the electric utility industry comes from coal. Car emissions 33% of US carbon dioxide emissions. Deforestation Agriculture Methane is 20 times more harmful than carbon dioxide as a greenhouse gas, but there is not nearly as much methane made.

Effects of Global Warming Polar ice caps have been melting rapidly. In 2006, almost all of the 300 glaciers worldwide are melting. Sea level rising quickly. Increased ocean temperatures Associated with more severe weather (hurricanes).

Source EPA.gov 2012

Source: National Geographic

This is what the US coastline would look like if all of the polar ice in the world melted.

Increased acidity in oceans. More carbon dioxide is being absorbed in the oceans, which makes carbonic acid. Acidic oceans are killing marine life.

Other Air Pollutants from Fossil Fuels If not for the CO2 then maybe for… Carbon Monoxide (CO) Volatile Organic Compounds (VOCs) Ozone (O3) Mercury Particulates Other Heavy Metals Nitrous Oxide (NO) Sulfur Dioxide (SO2) Unburned Hydrocarbons Source: College of Earth and Mineral Science PSU