Home Topics What Do Biogeochemical Cycles Connect?


Gardnerella vaginalis

Gardnerella Vaginalis

Definition Gardnerella vaginalis is the name of a micro-aerophilic coccobacillus found in the vaginal flora. Gardnerella vaginalis does not cause bacterial vaginosis (vaginal infection) unless...
Acetic Acid

Acetic Acid

Definition Acetic acid is a mildly corrosive monocarboxylic acid. Otherwise known as ethanoic acid, methanecarboxylic acid, hydrogen acetate or ethylic acid, this organic compound is...
Amino Acids

Amino Acids

Definition Amino acids are the building blocks of polypeptides and proteins and play important roles in metabolic pathway, gene expression, and cell signal transduction regulation....
BCAA supplements: a muscle myth?

Branched Chain Amino Acids

Definition The branched-chain amino acids or BCAAs, leucine, isoleucine, and valine are three of the nine nutritionally essential amino acids. These three ingredients form a...
Sulfuric acid

Sulfuric Acid

Definition Sulfuric acid (sulphuric acid) is a corrosive mineral acid with an oily, glassy appearance that gave it its earlier name of oil of vitriol....
Bile salt action in the gut

Bile Salts

Definition Bile salts are found in bile, a secretion produced by liver cells to aid digestion. Although bile is 95% water, bile salts are its...
The salivary glands

Submandibular Gland

Definition Submandibular glands are the second-largest salivary gland type, producing around 65% of our saliva when unstimulated (at rest). Located under the jaw, the exocrine...
Metaphase I

Metaphase I

Definition The first metaphase of meisosis I encompasses the alignment of paired chromosomes along the center (metaphase plate) of a cell, ensuring that two complete...
Prophase II

Prophase II

Definition During prophase II of meiosis II, four important steps occur. These are the condensing of chromatin into chromosomes, disintegration of the nuclear envelope, migration...


Definition Aldosterone (C21H28O5) is a mineralocorticoid hormone compound secreted by the adrenal gland cortex. It is part of the renin angiotensin aldosterone system or RAAS...

What Do Biogeochemical Cycles Connect?

The biogeochemical cycles on Earth connect the energy and molecules on the planet into continuous loops that support life. The basic building blocks of life like water, oxygen, carbon, sulfur, nitrogen and phosphorous are recycled and go back into their respective cycles repeatedly. The biogeochemical cycles also create reservoirs of these building blocks such as the water stored in lakes and oceans and sulfur stored in rocks and minerals.

The biogeochemical cycles have existed on Earth for billions of years and the elements that make up a modern-day human (or anything else on the planet) have been part of many other organisms and non-living molecules in the past. The process known as nucleosynthesis that occurred during and after the Big Bang was the ultimate source of all the materials that make up the universe. For example, the lighter elements hydrogen and helium formed within the first few minutes of the Big Bang and went on to help form the first stars. When the stars got old and eventually exploded, these elements went on to be incorporated into other cycles, processes, stars and planets in the universe. In addition to recycling elements and molecules, the explosion of stars also creates new materials like metals that are expelled into space and become part of the whole process.

Carbon cycle
The image above shows the carbon cycle, one of the biogeochemical cycles on Earth that recycles and stores the elements essential for life.


  • Nucleosynthesis. (n.d.). In Wikipedia. Retrieved June 25, 2017 from https://en.wikipedia.org/wiki/Nucleosynthesis
  • OpenStax, Biology. OpenStax. May 20, 2013. http://cnx.org/content/col11448/latest/