OXYGEN CYCLE

Oxygen:

OXYGEN: Is a chemical element with symbol O

and atomic number 8. Tasteless gas. Has no smell nor color. Comprises 22% of the air. Supports combustion.

Definition : Is the biogeochemical cycle that

describes the movement of oxygen with its three main reservoirs :

1. Atmosphere2. Biosphere3. Lithosphere

NB : Failure in the oxygen cycle within the hydrosphere can result in the development of Hypoxic zones.

Hypoxic zones- This is a condition caused by excessive nutrient pollution from human activities coupled with other factors which in turn deplete or lowers the oxygen level required by marine life.

Main Factor Driving Oxygen CyclePhotosynthesis : Is a process used by plants and other organisms to

convert light energy into chemical energy that can be later released to fuel the organisms activities.

This chemical energy is stored in carbohydrate molecules such as sugars which are synthesized from carbon dioxide and water.

Photosynthesis is derived from a Greek word Phõs -“light” and Synthesis– “putting together”.

Most plants, Algae and Cynobacteria perform photosynthesis and they are referred to as Autotrophs.

Photosynthesis is responsible for the modern earth’s atmosphere and life on earth.

Photosynthetic Reaction

6CO2 + 6H2O + Energy C6H12O6 + 6O2

Uses of Oxygen

Used : To make acids (sulfuric, nitric acid)

and other compounds. For boosting reaction rates and

oxidation of unwanted compounds. In medicine and healthcare

institutions. To generate energy. For destroying rocks in mining.

Oxygen in :Soil: This are the air spaces present in the

soil. This are the air spaces present in the

soil.. Its composition is 20%.

Water : Oxygen in water is known as

dissolved oxygen . Oxygen enters the water from the

atmosphere as it dissolves and mixes into the water surfaces.

Oxygen uptake rate (O.U.R.) is the rate at which oxygen is consumed by living organisms in the water. 

It appears as water bubbles.

Thank you very much.

NB: Question me after the class please!!!!

Conserve as much as you can!!!

Done By :

Paulus N. Nakashole16 March 2014