Cycles Unit Two

Earth’s Make-up Section one

Atmosphere The atmosphere is made up of 78% nitrogen and 21% oxygen. Only .004% of the atmosphere. It is made up of four parts.

Troposphere The troposphere is the layer that touches the Earth’s surface. This is where most of the weather occurs.

Stratosphere and Ozone The next layer above the troposphere is known as the stratosphere. The top of the stratosphere contains the ozone layer*. Without the ozone layer the UV radiation from the sun would destroy life on Earth.

Mesosphere and Thermosphere These are the outermost layers of the atmosphere with the mesosphere experiencing extreme colds and the thermosphere experiencing extreme highs.

Biosphere The biosphere is all the parts of the Earth that can support life. Organisms interact with all parts of the biosphere. This is from the tops of the highest mountains to the bottom of the deepest oceans.

Geosphere 3 Layers: 1.) Crust – 5-70km, the continental crust is thick and made up of light weight materials. The oceanic crust is made of denser materials but is thinner.

Mantle 2,900 km thick it is made of dense iron like materials.

Core 3,428 km radius, made nickel and iron at the center of the Earth. Parts are liquid while other parts are solid due to heat and pressure.

Section 2: Photosynthesis Photosynthesis* is the process in which plants, algae and some bacteria convert sunlight into chemical energy.

During photosynthesis, light energy transfers electrons from water to carbon dioxide, producing carbohydrates. The water is converted to oxygen during this process.

Cellular Respiration Cellular respiration* uses oxygen to turn glucose into ATP. The byproduct of the reactions that make this happen are carbon dioxide and water.

Biogeochemical Cycles Although chemicals may be abundant, they must undergo specific cycles to be usable.

Carbon Cycle How is carbon produced? Burning of fossil fuels. Volcanic eruptions. Erosion of limestone. Cow bodily functions. Destroying forest. Destruction of coral reefs. Farmers.

Carbon Cycle Combustion Respiration Sun Death waste Carbonification Decay Diffussion minning

Carbon Cycle The carbon is the basic building block of organic compounds it cycles through living and nonliving components of an ecosystem. Photosynthesis and cellular respiration allow it to move through the following parts of Earth in the following ways:

Biosphere Photosynthesis: Plants and algae use carbon dioxide to create nutrients through photosynthesis. Cellular Respiration: Carbon dioxide excreted from the body as a byproduct of cellular respiration.

Atmosphere Photosynthesis: Plants contain large amounts of Carbon, if they are burned they release this carbon into the atmosphere. Cellular Respiration: All animals excrete carbon dioxide, but some animals such as cows produce large amounts of carbon dioxide due to their digestion.

Hydrosphere Photosynthesis: Carbon is trapped in algae, which accumulates on the bottom of the ocean, which eventually forms crude oil. Cellular Respiration: The ocean emits and absorbs carbon dioxide through diffusion. Marine animals play a role in this emmision.

Geosphere Photosynthesis: Carbon is trapped in plant material which when trapped forms coal deposits. Cellular Respiration: As soil and organic material decays form bacteria, it will emit carbon dioxide.

Section Three: Cycles The following section explains how the remaining biogeochemical cycles move materials through each part of the Earth.

Nitrogen Cycle Hydrosphere: Enters through runoff and leaching of fertilizer, which can lead to eutrophication. Biosphere: Plants absorb nitrogen through bacteria in a process known as nitrification.

Nitrogen Cycle Atmosphere: Nitrogen exits the atmosphere through lightning fixation and enters it through decay and fossil fuel emissions Geosphere: It enters through the break down of organic material and leaching. It is also absorbed by plants after it is broken down.

Water Cycle Hydrosphere: Water enters the hydrosphere through precipitation and runoff, and it exits through evaporation. Biosphere: Water is consumed by living organisms and then it exits through respiration.

Water Cycle Atmosphere: Water enters the atmosphere through evaporation and then it exits through precipitation. Geosphere: It enters the geosphere through infiltration and then it exits through the zone of discharge.

Water Cycle Evaporation Condensation Precipitation Infiltration Runoff Discharge

Phosphorus Hydrosphere: Phosphorus enters through runoff due to erosion and farming. Biosphere: Decomposers break down phosphorus, plants absorb it, and then animals eat plants.

Phosphorus Atmosphere: It does not enter the atmosphere. Geosphere: Phosphorus is naturally found in rocks and soil, but it has to be broken down to be cycled through the other parts of Earth.

Discussion for the Test Gaia hypothesis Disappearance of tropical rain forest