Biochemical Cycles By: Danielle Delfino

The Water Cycle

The Water cycle, which is also called the Hydrologic cycle, is a cycle in which water travels from the sky to the land and back. The cycle includes Precipitation, Condensation, Groundwater, Collection, Evaporation, and Transpiration. There are no chemical reactions involved. It starts with evaporation. The earths surface is heated by the sun which causes water to turn from a liquid state into a gaseous state. Then condensation begins. After the water collects into little particles in the air, clouds form around the water as it begins to turn back into a liquid state. Then the water falls from the sky which is called precipitation. The water creates surface runoff and collects into ground water. Then the cycle starts all over again.

  • Chemical Reaction: The only chemical reaction in this cycle is photosynthesis
  • Inorganic compounds: Chloride, Sulfate, Iron, and Flouride
  • Organic Compounds: Carbon, Vegetation Roots, Microorganisms, Residues of organic matter transfer from soil to water
  • Impact of humans: Humans impact the water cycle through deforestation, irrigation, and harnessing hydroelectricity

The Nitrogen Cycle

The Nitrogen cycle can by carried out through geologic and physical processes. First nitrogen is absorbed into soil where bacterias break it down then it is taken in by plants, then animals eat the plants. The animals eventually die and the nitrogen is absorbed back into the soil.

  • Chemical Reactions: Fixation, Ammonification, Nitrification, and Denitrification.
  • Inorganic Compounds: Gaseous dinitrogen, Ammonia, Ammonium, Nitric oxide, Nitrous oxide, Nitrogen dioxide, Nitrite, Nitrate, Urea
  • Organic Compounds: A very diverse group of nitrogen-containing organic molecules including simple amino acids through to large complex proteins and nucleic acids in living organisms and humic compounds in soil and water.
  • Impact of humans: Humans can impact the nitrogen cycle by polluting, using cars, factories, deforestation, and many other things.

The Carbon Cycle

The Carbon cycle is the movement of carbon from living things to the environment. The cycle starts with plants taking in carbon dioxide from the air and using it to make food. Animals then eat the food and release the carbon back into the air through respiration.

  • Chemical Reactions: Photosynthesis, and Metabolism,
  • Inorganic Compounds: Carbon Dioxide, Methane
  • Organic Compounds: Anything that has the carbon in it
  • Human Impact: Humans can impact the carbon cycle through poor agricultural practices, burning fossil fuels, deforestation, and exhaling carbon dioxide

The Phosphorus Cycle

The phosphorus cycle is the movement of phosphorus through the earth. The cycle starts with sediments and rocks that weather over time and release phosphate that is then distributed into soils and waters. The phosphate is then taken in by a plant or animal and made organic; when the plant or animal dies, it is released back into the soil where bacteria and other microorganisms can break it down. The phosphorus can then end up into waters where it is made into sediments over time.

  • Chemical Reactions: phosphorus reacts vigorously with all the halogens at room temperature to form phosphorus trihalides, and chemuluminescence
  • Inorganic Compounds: Phosphorus in rocks, soil, sediments, and water.
  • Organic Compounds: Phosphate in plants and animals and the bacteria.
  • Impact of humans: Humans can impact the phosphorus cycle mainly through the use of fertilizers, but anything water can run off of can affect the cycle so many human things can affect it.


Created with images by NASA Goddard Photo and Video - "Hubble Goes High Def to Revisit the Iconic 'Pillars of Creation'"

Made with Adobe Slate

Make your words and images move.

Get Slate

Report Abuse

If you feel that this video content violates the Adobe Terms of Use, you may report this content by filling out this quick form.

To report a Copyright Violation, please follow Section 17 in the Terms of Use.