Introduction to Photosynthesis

The cycle considering the biological, geological, and chemical aspects of Earth's systems, essential for maintaining life and ecosystem health

A process where carbon moves between the atmosphere, land, oceans, and living things.

A process where organisms break down glucose to release energy, producing carbon dioxide and water.

Plants use carbon dioxide from the air to create food (sugars), releasing oxygen.

The transfer of carbon through organisms as they eat each other.

The breakdown of dead organisms and waste, returning carbon to the environment.

Process of dead non-decomposing material turning into fossil fuels like coal, oil, and gas.

Volcanoes release carbon dioxide into the atmosphere by releasing molten rock.

The ocean holds significantly more carbon than the atmosphere, absorbing CO2 and converting it into carbonic acid, bicarbonate, and carbonate ions.

Burning wood, fossil fuels, and other carbon-containing materials releases stored carbon into the atmosphere, disrupting the natural carbon cycle.

Oxygen makes up a substantial portion of Earth's mass, mostly found in oxides within minerals like silicon dioxide.

The continuous movement of oxygen through the atmosphere, oceans, and Earth's crust, involving processes such as photosynthesis, cellular respiration, and volcanic activity.

Chemical reactions involving the transfer of electrons between atoms, resulting in changes in oxidation states.

A process where an element loses electrons or forms bonds with oxygen, increasing its oxidation state.

Photosynthesis releases oxygen back into the atmosphere, countering the consumption of oxygen by oxidation.

The upper atmosphere's oxygen is key to ozone (O3) formation and breakdown, part of the processes associated with the atmosphere.

A form of oxygen (O3) found in the stratosphere, protecting Earth from harmful UV radiation.

Ultraviolet (UV) radiation breaks apart oxygen molecules (O2), creating individual oxygen atoms that combine with other O2 molecules to form ozone (O3).

Ozone absorbs UV radiation, preventing it from reaching Earth's surface, protecting life from its harmful effects.

Nitrogen (N2) is the most abundant gas in the atmosphere, essential for life, but in its original form, it's unusable by most organisms.

The process of converting nitrogen gas (N2) into usable forms like ammonia (NH3) or ammonium (NH4+) by certain bacteria.

Decomposers break down dead organisms and waste, releasing ammonium (NH4+), which can be reused by plants.

Plants absorb ammonia and nitrate, using them to build essential molecules like DNA and proteins.

Nitrifying bacteria in the soil convert ammonium (NH4+) into nitrate (NO3-), a form easily absorbed by plants.

The downward movement of rock, soil, and regolith under the influence of gravity.

The process of wearing away and transporting rock, soil, and sediment by agents like water, wind, or ice.

The movement of sulfur through Earth's systems (biosphere, geosphere, hydrosphere, atmosphere). It's essential for life and affects environmental processes.

Sulfur is primarily stored in the lithosphere (Earth's crust and upper mantle).

Sulfur enters the atmosphere through volcanic eruptions, hot springs, decaying organic matter, and oceanic organisms.

Sulfate aerosols are tiny particles in the atmosphere formed from sulfur compounds. They can affect cloud formation and climate.

Sulfuric acid from the atmosphere dissolves in rainwater and falls as acid rain, bringing sulfur back to the Earth's surface.

Sulfur occurs in rocks mainly as sulfide minerals like pyrite (FeS2) and sulfate minerals like gypsum (CaSO4). It's found in the Earth's crust, often in sedimentary or igneous rock layers.

Physical weathering and erosion break down sulfur-containing minerals, releasing sulfur into the soil and water as sulfate ions (SO42-).

Plants take up sulfate ions (SO42-) from the soil and use them to create organic molecules like amino acids (cysteine and methionine), which are part of proteins.

Animals consume sulfur by eating plants or other animals. This sulfur becomes part of their tissues, essential for protein synthesis and cellular function.

When plants and animals die, decomposers like bacteria and fungi break down their organic sulfur compounds, releasing sulfur back into the soil as sulfate ions (SO42-).

Phosphorus is found primarily in bones and teeth as calcium phosphate. The rest is in soft tissues and cells, crucial for DNA, RNA, and ATP.

Phosphorus is a building block for nucleic acids like DNA and for phospholipids, which form cell membranes.

Phosphorus is essential for plant growth.

The movement of phosphorus through the Earth's environment, including soil, water, organisms, and rocks.

Phosphorus in rocks and minerals primarily exists in the form of phosphate minerals, like apatite (Ca5(PO4)3(F, CI, OH)).

Plants absorb phosphate ions from the soil through their roots, using them for processes like photosynthesis and growth.

When organisms die or excrete waste, phosphorus gets released back into the soil through decomposition by detrivores.

Excessive phosphorus can be washed away by rain or carried by surface water, leading to pollution and eutrophication.

Over long periods, sedimentary phosphorus from oceans and lakes can be uplifted by tectonic activity, returning to land.

Unlike nitrogen and carbon, phosphorus does not have a significant gaseous phase in the environment.

The phosphorus cycle is relatively slow compared to other nutrient cycles, mainly due to its storage in rocks and minerals.