ABSTRACT
The process of photosynthesis is central to the inclusion of plants in a Closed-Environment life support system (CELSS) for space habitats of a mission duration and crew size that render food and atmospheric regeneration desirable. Within the chloroplasts of green plants the energy from photosynthetically active radiance (PAR) of wavelengths between 400 and 700 nm is utilized for "photolysis" of water to hydrogen and hydrozyl ions. The reducing potential of the hydrogen ions is utilized to reduce carbon dioxide to the level of simple sugars, while the oxidizing potential of the hydroxyl ions is utilized to evolve oxygen. These biochemical processes of photosynthesis are summarized in the following reactions: https://www.w3.org/1998/Math/MathML"> 4 H 2 O → P A R 4 ( H + ) + 4 ( O H − ) ( 1 ) https://s3-euw1-ap-pe-df-pch-content-public-u.s3.eu-west-1.amazonaws.com/9780429051968/63d0f556-5945-448b-9fee-68bcb558057e/content/math2.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> https://www.w3.org/1998/Math/MathML"> 4 ( H + ) + C O 2 → ( C H 2 O ) + H 2 O ( 2 ) https://s3-euw1-ap-pe-df-pch-content-public-u.s3.eu-west-1.amazonaws.com/9780429051968/63d0f556-5945-448b-9fee-68bcb558057e/content/math3.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> https://www.w3.org/1998/Math/MathML"> 4 ( O H − ) → 2 H 2 O + O 2 ( 3 ) https://s3-euw1-ap-pe-df-pch-content-public-u.s3.eu-west-1.amazonaws.com/9780429051968/63d0f556-5945-448b-9fee-68bcb558057e/content/math4.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/>
